Home

User login

You are here

The Watchers - EARTH

Subscribe to The Watchers - EARTH feed
Watching the world evolve and transform
Updated: 1 hour 52 min ago

May 2013 Skywatching guide

Tue, 04/30/2013 - 17:22

May 2013 brings few interesting sky events. This years Eta Aquarid meteor shower will peak on May 6 with expected zenith hourly rate of 55 meteors per hour. We are about to experience annular solar eclipse on May 9/10. Annularity will be visible from northern Australia and the southern Pacific Ocean, with the maximum of 6 minutes 3 seconds visible from the Pacific Ocean east of French Polynesia.

On May 24th, penumbral lunar eclipse will be visible to observers in North and South America, Western Europe and Western Africa. It will be visually imperceptible due to the small entry into the penumbral shadow. Jupiter, Mercury and Venus get together. Virgo Cluster and Sombrero galaxy could be seen by using binoculars. And there’s many more. Watch this videos below for more info.

 

 

Credit: Space.com, JPL

Featured image: Annular solar eclipse (Youtube screenshot)

May 2013 Skywatching guide

Related posts:

  1. ESA’s Proba-2 recorded three partial solar eclipses last night Proba-2 sun observing satellite experienced three partial solar eclipses last...
  2. Annular solar eclipse today An annular solar eclipse will be visible from a 240...

Tropical Cyclone Zane moving toward Cape York, Australia

Tue, 04/30/2013 - 17:00

Australian Bureau of Meteorology reports that Tropical Cyclone Zane is currently moving towards the west. The system should adopt a west-northwest track over the next 6 to 12 hours and accelerate slightly under the influence of a developing mid-level ridge across Queensland and the central Coral Sea. A Cyclone warning is current for coastal areas from Mapoon to Cape York to Cooktown, and warning for areas from Cooktown to Cape Tribulation has been cancelled.

The forecasters at the Joint Typhoon Warning Center expect Zane to track to the west-northwest and cross the Cape York Peninsula on May 1 and then emerge into the Gulf of Carpentaria. At this time, Zane isn’t expected to make a second landfall in Australia and is forecast to pass through the Arafura Sea.

TC Zane visible on IR satellite image on April 30, 2013 (Credit: CIMSS)

 

Currently, TC Zane is Category 2 storm, with wind gusts up to 150 km/h is moving towards the west-northwest. The system is expected to continue moving west-northwest during the day while slowly weakening and cross the far northern Queensland coast between Orford Ness and Cape Melville early on morning on May 1, 2013.

Zane surged in intensity on April 29, 2013 as a boost in poleward outflow occurred simultaneously with a boost in gradient level flow due to an anticyclone moving off-shore of Queensland. The system will remain in its current environment of 29 degree Celsius surface waters and 15-20 knots of vertical wind shear through landfall over the Cape York peninsula.

This infrared image taken from the AIRS instrument aboard NASA’s Aqua satellite on April 30 at 0317 UTC (11:17 p.m. EDT on April 29 shows that the strongest convection and thunderstorms (purple) around the center of circulation as System 92P organized into Tropical Storm Zane (Credit: NASA JPL, Ed Olsen)

 

According to latest report by Joint Typhoon Warning Center (JTWC), Tropical Cyclone Zane (TC 23P), is located approximately 218 nm northeast of Cairns, Australia. The system is moving westward at speed of 05 knots. Animated infrared satellite imagery indicates the system has slowed and begun a slight turn equatorward during the past 12 hours.

TC Zane forecast track by JTWC

 

The system is expected to remain weak once it emerges into the Gulf of Carpentaria. TC Zane is being driven westward by a mid- to high-level anticyclone over the Coral Sea, which is weakening and pulling away towards the Solomon Islands. In anticipation of the weaker steering influence, the JTWC track forecast hedges a little bit slower and poleward, but remains close to, consensus. Intensity guidance consistently indicates rapid weakening and dissipation of the system over the Gulf of Carpentaria, primarily due to vertical wind shear.

Although animated water vapor imagery is beginning to reveal some increased subsidence over the western side of the storm, solid radial outflow persists along with a weak poleward tap.

Visible Floater satellite image of TC Zane on April 30, 2013 (Credit: MTSAT/NOAA)

 

There is a high level of uncertainty with the forecast, as the system moves back into the gulf of Carpentaria, due to the mix of dry air entrainment and favorable surface conditions competing for the dominant influence on intensity.

 

TC Zane (Australian Bureau of Meteorology)

 

Satellite Animations

 

Featured image: Satellite image of TC Zane on April 30, 2013 (Credit: LANCE/MODIS/WorldView)

Tropical Cyclone Zane moving toward Cape York, Australia

Related posts:

  1. Tropical Cyclone Narelle formed off Australia coast Tropical Cyclone Narelle developed off northwestern Australia coast with the...
  2. New tropical depression forms off the coast of Australia According to latest report by Joint Typhoon Warning Center, Tropical...

Strong M 5.3 earthquake off the coast of Antigua and Barbuda

Tue, 04/30/2013 - 04:17

A  strong earthquake registered asM 5.3 occurred off the coast of Barbuda in eastern Caribbean, on April 30, 2013 at 06:56:47 UTC. The epicenter was located in sea, about 50 km off the coast or 37 km (22 miles) WSW of Codrington, Barbuda, 51 km (31 miles) NW of Saint John’s, Antigua and Barbuda, 65 km (40 miles) ENE of Basseterre, Saint Kitts and Nevis, 136 km (84 miles) NNW of Sainte-Rose, Guadeloupe at coordinates 17.488°N, 62.142°W. USGS reported M 5.3 at depth of 48.9 km (30.4 miles) and EMSC registered M 5.4 at depth of 48 km.

 

Magnitude5.3Date-TimeLocation17.488°N, 62.142°WDepth48.9 km (30.4 miles)RegionANTIGUA AND BARBUDA REG, LEEWARD ISLANDSDistances37 km (22 miles) WSW of Codrington, Barbuda
51 km (31 miles) NW of Saint John’s, Antigua and Barbuda
65 km (40 miles) ENE of Basseterre, Saint Kitts and Nevis
136 km (84 miles) NNW of Sainte-Rose, GuadeloupeLocation Uncertaintyhorizontal +/- 13.5 km (8.4 miles); depth +/- 8.2 km (5.1 miles)ParametersNST= 67, Nph= 68, Dmin=42.3 km, Rmss=0.87 sec, Gp= 86°,
M-type=body wave magnitude (Mb), Version=9Source
  • Magnitude: USGS NEIC (WDCS-D)
    Location: USGS NEIC (WDCS-D)
Event IDusb000gih0

USGS community internet intensity map

 

Antigua and Barbuda is a twin-island nation lying between the Caribbean Sea and the Atlantic Ocean. It consists of two major inhabited islands, Antigua and Barbuda, and a number of smaller islands. Separated by a few nautical miles, Antigua and Barbuda are in the middle of the Leeward Islands, part of the Lesser Antilles, roughly at 17 degrees north of the Equator.

Powerful M7.5 earthquake occurred in the area in 1974.

Featured image: Google 2013. Image: TerraMetrics 2013.

Strong M 5.3 earthquake off the coast of Antigua and Barbuda

Related posts:

  1. Hispaniola island rock is surprising remnant of ancient supercontinent Unusual lavas in the Caribbean apparently originated from the lost,...

Strong and shallow M 5.9 earthquake struck Azores Islands, Portugal

Tue, 04/30/2013 - 04:05

A strong and shallow earthquake magnitude M 5.9 struck Azores Islands, Portugal on April 30, 2013 at 06:25 UTC.  Epicenter was located in between Sao Miguel and Santa Maria islands; 29 km (18 miles) ESE of Furnas, Portugal and 58 km (36 miles) E of Ponta Delgada, Portugal. Centro de Vulcanologia e Avaliação de Riscos Geológicos – CIVISA is also reporting a M 5.9 earthquake. Depth is still uncertain. EMSC is reporting epicenter at depth of 2 km, USGS (set by location program) still reports depth of 10 km.

There are 130 000 people within 100 km.

The area is experiencing increased seismic activity (as shown on the map below). Numerous aftershocks were reported after M 5.9 today.  Azores are considered as seismically very active region.  However, these kinds of earthquakes, so close to islands, are not happening very often. Check ER for list of latest updates.

List of latest earthquakes – Azores Islands, Portugal. Credits: Centro de Vulcanologia e Avaliação de Riscos Geológicos. Google 2013 – Image: NASA, Terrametrics 2013.

 

Magnitude5.9Date-Time
  • Tuesday, April 30, 2013 at 06:25:23 UTC
  • Tuesday, April 30, 2013 at 06:25:23 AM at epicenter
Location37.655°N, 25.007°WDepth10 km (6.2 miles) set by location programRegionAZORES ISLANDS, PORTUGALDistances29 km (18 miles) ESE of Furnas, Portugal
58 km (36 miles) E of Ponta Delgada, Portugal
222 km (137 miles) ESE of Angra do Heroismo, Portugal
920 km (571 miles) NW of Camara de Lobos, PortugalLocation Uncertaintyhorizontal +/- 7.5 km (4.7 miles); depth fixed by location programParametersNST=110, Nph=110, Dmin=>999 km, Rmss=0.9 sec, Gp= 43°,
M-type=teleseismic moment magnitude (Mw), Version=2Source
  • USGS NEIC (WDCS-D)
Event IDus2013pqaf

 

Major Tectonic Boundaries: Subduction Zones -purple, Ridges -red and Transform Faults -green

 

Featured image: Centro de Vulcanologia e Avaliação de Riscos Geológicos. Google 2013 – Image: NASA, TerraMetrics 2013.

Strong and shallow M 5.9 earthquake struck Azores Islands, Portugal

Related posts:

  1. Experts concerned with abnormal seismic activity – Azores Experts in the Azores have alerted the population of São...

Dust across the Mediterranean Sea

Mon, 04/29/2013 - 17:53

A cloudbank stretched across the Mediterranean Sea from northern Algeria to southern France for the last few days. Saharan dust streaked the clouds, extending hundreds of kilometers from southeast to northwest. One especially noticeable dust plume passed over the island of Mallorca.


The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite captured this natural-color image on April 29. National borders and coastlines are marked with black outlines.

 

 

The sand seas of the Sahara Desert provide ample material for dust plumes, and dust storms rank among the most frequent natural hazards for many northern African countries. Weather fronts often stir dust, and the same weather front that brought clouds to this region in late April likely also raised the dust.

 

Source: EarthObservatory

Featured image: MODIS satellite image of dust across Mediterranean on April 29, 2013

Dust across the Mediterranean Sea

Related posts:

  1. Dust storm in Utah Dust and clouds mingled over Utah in late February 2012....
  2. Dust storm over Syria and Iraq Dust plumes blew through Syria and Iraq in early December...

Etna erupting again – 13th paroxysm in 2013

Mon, 04/29/2013 - 16:37

Strong strombolian activity and frequent ash emissions that continued throughout the whole night on April 27, 2013, were a prelude to the 13th paroxysm (lava fountaining) of this year at Etna’s New Southeast Crater. The strombolian activity had begun already on April 21, just one day after the April 2′ paroxysm.

On the evening of April 26, 2013 a gradual increase in both the eruptive activity and in the volcanic tremor amplitude had started.

Shortly after the sunset on April 27, 2013, the paroxysmal phase began with lava fountains 300-500 m high.

Emission of lava flows from the southeastern and northeastern flanks of the New Southeast Crater cone and from the “saddle” between the two Southeast Crater cones, formed small lava flows toward south and north.

A pyroclastic flow, which advanced about 1 km toward the Valle del Bove, was generated when a portion of the eastern flank of the cone collapsed.

Furthermore, a tephra cloud formed, and was blown by the wind to the northeast, producing ash and lapilli falls in the area of Linguaglossa, and also in Taormina and Messina.

Here is an amazing video of this Saturday’s eruption:

 

The entire paroxysmal episode lasted about 2 hours, but lava emission toward southeast continued for many hours and stopped during the forenoon of April 28, 2013.

Sources: INGV CataniaVolcanoDiscovery

Featured image:  Lava fountains from the New SE crater (Etna Trekking webcam)

Etna erupting again – 13th paroxysm in 2013

Related posts:

  1. 14th paroxysm of SE crater of Etna in progress The 14th paroxysm of Etna’s New SE crater is in...
  2. A new paroxysm at Etna’s New Southeast Crater Only two days passed since the last eruption, and new,...

How did this year’s Lyrids perform?

Sun, 04/28/2013 - 03:45

During the last week, our planet has been passing through debris from Comet Thatcher, source of the annual Lyrid meteor shower. On the nights around April 22nd, while the peak of this years meteor shower was, All Sky Fireball Network (NASA) reported more than 30 Lyrids as bright as Venus. International observers registered as many as 25 meteors per hour.

Here is a diagram of the orbits of Lyrids detected by NASA’s All Sky Fireball network:

The red splat in this diagram marks the location of Earth, the orbits of the meteoroids are green ellipses, triangulated by multiple cameras in the meteor network.

 

Bill Cooke, lead scientist for NASA’s Meteoroid Environment Office, explains that the purple ellipse is the orbit of Comet Thatcher. The orbits of the comet and the meteoroids match up nicely, he adds.

 

Astrophotographer B. G. Boyd sent in a photo of a Lyrid meteor over Tucson, Arizona, taken on April 22, 2013 (Credit: B.G. Boyd)

 

This years Lyrid fireballs penetrated Earth’s atmosphere as deeply as 44 miles above the planet’s surface, flying at an average speed of 105,000 mph, says Cooke.

The annual shower is past its climax now and is subsiding as Earth leaves the debris stream.


Source: SpaceWeather

Featured image: Astrophotographer Jonathan S. McElvery sent in a photo of a Lyrid meteor over Westborough, US, taken April 22, 2013.

How did this year’s Lyrids perform?

Related posts:

  1. Earth Day 2012 Lyrid meteor shower Earth Day in 2012 coincided with the Lyrid maximum. Many observers...
  2. Lyrid meteor shower peaks on April 22, 2013 Earth is approaching the debris field of ancient Comet Thatcher,...

Planetary alignment / earthquake watch – April 27-28, 2013

Sat, 04/27/2013 - 08:20

Two very strong planetary alignments (Mars-Earth-Sun-Saturn), supported by (Mercury-Venus-Jupiter) fall during this time-frame with an added influence involving the Asteroid Ceres and astrological aspects involving Pluto indicate a potential for a 7.8 magnitude earthquake on either one of these forecasted days.

This is my own analysis using heliocentric imagery, geocentric portrait and harmonic translations to predict possible effects here on Earth. I am using astrological aspects in this forecast in-conjunction with lunar modulations.

 

Targeting a large Coronal Hole (CH566) in Northern Hemisphere of the solar corona: after further analysis I have isolated an area (16-24°N latitude) this Coronal Hole may itself be a foreshadow for a 7.8 magnitude earthquake in one of these listed locations during this watch period:

Taiwan
Luzon, Philippines
Mariana Islands
Dominican Republic
Puerto Rico
Myanmar

Forecast – (7.5 -7.8 Magnitude)
Time frame suggests: April 27-28, 2013

Results will be annotated at the end of this video.

Video and analysis: SolarWatcher

Featured image: Solar System Scope

Planetary alignment / earthquake watch – April 27-28, 2013

Related posts:

  1. Planetary alignment / Earthquake watch for the year 2013 In video below the author is using heliocentric imagery, geocentric...
  2. Strong kinetic migration possible – Volcano / Earthquake Watch – October 12 – 17, 2012 An earthquake in Balleny Islands region from October 9th could...

Cassini – meteoroids are breaking into streams of rubble and crashing into Saturn’s rings

Sat, 04/27/2013 - 07:49

New results from NASA’s Cassini spacecraft show that small meteoroids are breaking into streams of rubble and crashing into Saturn’s rings.

Saturn’s rings are the only place besides Earth, the moon, and Jupiter where researchers along with amateur astronomers have been able to observe impacts as they happen, as this new observations show.

By studying the impact rate of meteoroids from outside the Saturn’s system scientists can better understand how different planet systems in the Solar System formed.

There are a lot of small, speeding objects in our Solar System. Planetary bodies are very often pummeled by them. The meteoroids at Saturn measure from about one-half inch to several yards (1 centimeter to several meters) in size. Experts needed years to distinguish tracks left by nine meteoroids in 2005, 2009 and 2012.

Five images of Saturn’s rings, taken by NASA’s Cassini spacecraft between 2009 and 2012, show clouds of material ejected from impacts of small objects into the rings. Clockwise from top left are two views of one cloud in the A ring, taken 24.5 hours apart, a cloud in the C ring, one in the B ring, and another in the C ring. Arrows in the annotated version point to the cloud structures, which spread out at visibly different angles than the surrounding ring features.
The clouds of ejected material were visible because of the angle sunlight was hitting the Saturn system and the position of the spacecraft. The first four images were taken near the time of Saturn equinox, when sunlight strikes the rings at very shallow angles, nearly directly edge-on. During Saturn equinox, which occurs only every 14.5 Earth years, the ejecta clouds were caught in sunlight because they were elevated out of the ring plane. The last image was taken in 2012 at a very high-phase angle, which is the sun-Saturn-spacecraft angle. This geometry enabled Cassini to see the clouds of dust-sized particles in the same way that dust on a surface is easier to see when the viewer is looking toward a light source.
The angle that the clouds are canted gives the time elapsed since the cloud was formed (see PIA14941). The A ring cloud formed 24 hours before its first apparition in the top left box; it formed 48.5 hours before the top middle image. The other three clouds were approximately 13 hours, four hours, and one hour old (respectively) at the times they were seen. See PIA11674 for more information on ring impacts.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA’s Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo. Image Credit: NASA/JPL-Caltech/Space Science Institute/Cornell

 

The rings of Saturn act as very effective detectors of many kinds of surrounding phenomena, including the interior structure of the planet and the orbits of its moons, as results provided by Cassini have already shown.

A good example would be a subtle but extensive corrugation that ripples 12,000 miles (19,000 kilometers) across the innermost rings tells of a very large meteoroid impact in 1983.

These new results imply the current-day impact rates for small particles at Saturn are about the same as those at Earth – two very different neighborhoods in our Solar System, and this is exciting to see, explains Linda Spilker, Cassini project scientist at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif.

Spilker adds that it took Saturn’s rings acting like a giant meteoroid detector – 100 times the surface area of the Earth – and Cassini’s long-term tour of the Saturn system to address this question.

A special opportunity to observe the debris left by meteoroid impacts presented on the Saturnian equinox in summer 2009.

At that time the very shallow sun angle on the rings made the clouds of debris to look bright against the darkened rings in pictures from Cassini’s imaging science subsystem.

We knew these little impacts were constantly occurring, but we didn’t know how big or how frequent they might be, and we didn’t necessarily expect them to take the form of spectacular shearing clouds, said Matt Tiscareno, lead author of the paper and a Cassini participating scientist at Cornell University in Ithaca, N.Y.

He went on to explain that the sunlight shining edge-on to the rings at the Saturnian equinox acted like an anti-cloaking device, so these usually invisible features became plain to see.

Tiscareno and his colleagues now presume meteoroids of this size probably break up on a first encounter with the rings, producing smaller, slower pieces that then enter Saturn’s orbit. When these secondary meteoroid bits impact into the rings they spawn the clouds.

The tiny particles creating these clouds have a range of orbital speeds around Saturn. These clouds they produce are soon pulled into diagonal, extended bright streaks.

According to Jeff Cuzzi, Saturn’s rings are unusually bright and clean, leading some to suggest that the rings are actually much younger than Saturn. Cuzzi is a co-author of the paper and a Cassini interdisciplinary scientist specializing in planetary rings and dust at NASA’s Ames Research Center in Moffett Field, Calif.

He adds that to assess this dramatic claim, we must know more about the rate at which outside material is bombarding the rings. This latest analysis helps fill in that story with detection of impactors of a size that we weren’t previously able to detect directly, concludes Cuzzi.

Source: NASA

Featured image credit: NASA/JPL-Caltech/Space Science Institute/Cornell

Cassini – meteoroids are breaking into streams of rubble and crashing into Saturn’s rings

Related posts:

  1. Stunning views of Venus through Saturn’s rings The international Cassini spacecraft took amazing images of Venus shining through...
  2. Saturn and Earth line up for an amazing view of the golden planet If you have any interest in astronomy you have probably...

Pars aerial rescue robot – rescuing drowning individuals close to coastlines

Sat, 04/27/2013 - 05:19

Pars is an aerial rescue robot designed and built for saving human lives. According to RTS Lab, which designed it, Pars uses new technologies that help guide and navigate it, including sound and image processing, autopilot, artificial intelligence and an array of sensors.

One of the main purposes for which Pars is made is rescuing drowning individuals close to coastlines.

The robot can rapidly be guided towards people who’re drowning off the coastline and then activate its savior system which releases life tubes.

It can also be used in many other missions like maritime monitoring, aid in firefighting, precise positioning and recording film from dangerous pathways for rescue missions.

Many innovations have been implemented in the design of Pars.

The robot is waterproof and has the ability to land on the sea. Controlled from a central control cabin, on ships, Pars will be given its own platform and will be controllable directly through the ship’s control cabin.

It also has the ability to return back to the platform through GPS positioning, where it charges its batteries.

RTS Lab, based in Iran, further explain that Pars is equipped for saving three lives in one operation, but that can be increased to fifteen by using chemical material for bloating the life pads. The robot has been designed with a FLIR heating camera and LED lightening, which will be useful during nighttime operations.

Amin Rigi, Saeid Talebi, Masoud Noroozi, Hossein Saffari, Majid Saeidi and Amin Mirakhorli are owners of the Pars aerial rescue robot idea. The team started thinking about the project when they heard about people who had drowned in the Caspian Sea, north of Iran. The data they have collected showed that out of 46 500 people who had been in drowning situations over the past 8 years, 1100 had perished. The motive behind this project was to save human lives.

Pars is controlled by an array of motors, sensors, control circuits, mechanical systems and microcontroller programming. Rescue pads are released and controlled through several servo motors, which get a signal from the microprocessor. The platform’s base uses small conductive blocks for charging the robot, charging procedure starts only once the battery level goes below a pre-determined limit. In a scenario when Pars runs out of battery over the sea, it has the capability to automatically land itself on the sea surface.

According to Amin Rigi, Director, RTS Lab, a new prototype is in development and coastline tests are planned for the next few months.

Until now the manufacturing of primary functions has been finished. All of the functions the robot is going to have are impressive, but not all of them have been implemented. The team behind the project says that they have used three-axel accelerometers and gyroscopes, GPS, Barometer and compass, only the ultrasonic sensors are yet to be implemented.

Funding needed

Funding and investment are needed for mass production. The team claims that up till now all expenses related to development have been covered by them. RTS Lab estimate cost for industrial prototype of Pars aerial rescue robot between $30,000 to $40,000. There is still no definitive word on the expected release timeframe and final price.

Pars aerial rescue robot – rescuing drowning individuals close to coastlines

No related posts.

Saturn and Earth line up for an amazing view of the golden planet

Sat, 04/27/2013 - 04:18

If you have any interest in astronomy you have probably seen dozens if not hundreds of breathtaking images of the universe and our Solar System. Those images are usually acquired by some of Earth’s best spacecrafts, like Hubble, Cassini, Messenger and others who beam back gigabytes of jaw dropping images every year.

After seeing many of these amazing photos some people start to feel a bit indifferent.

Well, at the end of this April Saturn will put on a display that might just bring their enthusiasm back.

And no space probe is required to see it, just set up a telescope in your backyard. Even the one you bought at your local department store might do.

You have to point your optics towards the constellation Virgo, Saturn is there, not far from the bright star Spica.

Saturn will make its closest approach to Earth on April 28, 2013, and at that time it will appear bigger and brighter than at any other time in 2013.

This event is called ˝the opposition˝, because Saturn will be opposite of Sun in the skies of Earth. The rings brighten for a few days around opposition due to the Seeliger effect: the solid particles of the rings preferentially reflect sunlight back in the direction it came from, more than Saturn’s cloud tops do.

Image showing the opposition of Saturn on April 28, 2013

 

The ringed planet rises at sunset, soars almost overhead at midnight, and stays up throughout the night.

To the naked eye Saturn at opposition is as bright as a 1st magnitude star, which makes it relatively easy to spot.

 

Saturn is the most distant of the five planets easily visible to the naked eye, the other four being Mercury, Venus, Mars and Jupiter (Uranus and occasionally 4 Vesta are visible to the naked eye in very dark skies). Saturn appears to the naked eye in the night sky as a bright, yellowish point of light whose apparent magnitude is usually between +1 and 0. It takes approximately 29½ years to make a complete circuit of the ecliptic against the background constellations of the zodiac. Most people will require optical aid (large binoculars or a telescope) magnifying at least 20× to clearly resolve Saturn’s rings.

While it is a rewarding target for observation for most of the time it is visible in the sky, Saturn and its rings are best seen when the planet is at or near opposition (the configuration of a planet when it is at an elongation of 180° and thus appears opposite the Sun in the sky). During the opposition of December 17, 2002, Saturn appeared at its brightest due to a favorable orientation of its rings relative to the Earth, even though Saturn was closer to the Earth and Sun in late 2003.

Meanwhile, NASA’s Cassini spacecraft is circling Saturn, exploring the planet and its environment at point-blank range.  Since it reached the Saturn system in 2004, Cassini has found a moon with “tiger stripes” spewing geysers of salty water; an electrical storm big enough to swallow Earth; methane lakes and rain on Titan; braids, spokes and other strange ripples in Saturn’s rings; a hexagonal cloud system surrounding Saturn’s north pole; a satellite that looks like a sponge, and much more.

Sources: NASAtelevision, Science@NASAWikipedia

Saturn and Earth line up for an amazing view of the golden planet

Related posts:

  1. Stunning views of Venus through Saturn’s rings The international Cassini spacecraft took amazing images of Venus shining through...
  2. 2011 Skywatching Guide: Planets in the Solar System The planets of our solar system are at tomes some...

Water in Jupiter’s atmosphere came from 1994 comet impact

Fri, 04/26/2013 - 02:30

Observations by ESA’s Herschel space observatory have revealed origin of water’s mysterious presence in Jupiter’s atmosphere. Using sensitive spectral imaging, researchers were able to confirm that water came from historic comet impact in July 1994.

During July 1994, comet Shoemaker-Levy 9 collided with Jupiter after breaking apart. Comet’s fragments of up to 2 km in diameter struck the gas giant over days leaving prominent scars for months. Being first direct observation of such an unusual extraterrestrial collision, it received wide media coverage and was closely observed by astronomers.

This mosaic of WFPC-2 images shows the evolution of the G impact site on Jupiter (the 21 comet fragments of Shoemaker-Levy 9 were each assigned a corresponding letter to identify the impact site; G represents the 7th fragment to strike the planet. It was also the largest impact.). Credits: R. Evans, J. Trauger, H. Hammel and the HST Comet Science Team

 

After being launched in 1995, observations by ESA’s Infrared Space Observatory had shown presence of water in Jupiter’s upper atmosphere — planet’s stratosphere 15 years ago. Among several hypotheses, possibility of water rising from internal source was rejected given it cannot escape Jupiter’s troposphere. Another possible source of water would be a steady rain of small interplanetary dust particles onto Jupiter. But, in this case, the water should be uniformly distributed across the whole planet and should have filtered down to lower altitudes.

Also, one of Jupiter’s icy moons could deliver water to the planet via a giant vapor torus, as Herschel has seen from Saturn’s moon Enceladus, but this too has been ruled out. None of Jupiter’s large moons is in the right place to deliver water to the locations observed.

There was a consensus among astronomers that water came from outside, through impact of an external body — pointing Shoemaker-Levy 9 to be responsible. Yet there wasn’t evidence to support this speculation.

Distribution of water in the stratosphere of Jupiter as measured with ESA’s Herschel space observatory with the PACS instrument at 66.4 microns. The data have been superimposed over an image of Jupiter taken at visible wavelengths with the NASA/ESA Hubble Space Telescope. Credits: Water map: ESA/Herschel/T. Cavalié et al.; Jupiter image: NASA/ESA/Reta Beebe (New Mexico State University)

 

The challenge was to map the vertical and horizontal distribution of water’s chemical signature, which Herschel’s sensitive infrared telescope was able to tackle. Based on observations by HIFI and PACS instruments on board Herschel observatory during 2009-10, mission scientists explored water in Jupiter’s atmosphere. Thibault Cavalié of the Laboratoire d’Astrophysique de Bordeaux, lead author of the paper published in Astronomy and Astrophysics said,

“Only Herschel was able to provide the sensitive spectral imaging needed to find the missing link between Jupiter’s water and the 1994 impact of comet Shoemaker-Levy 9. According to our models, as much as 95% of the water in the stratosphere is due to the comet impact.”

Herschel’s observations found that there was 2–3 times more water in the southern hemisphere of Jupiter than in the northern hemisphere, with most of it concentrated around the sites of the 1994 comet impact. Additionally, it is only found at high altitudes. Dr Cavalié further said,

“All four giant planets in the outer Solar System have water in their atmospheres, but there may be four different scenarios for how they got it. For Jupiter, it is clear that Shoemaker-Levy 9 is by far the dominant source, even if other external sources may contribute also.”

To explore and map the distribution of Jupiter’s atmospheric ingredients in detail, ESA’s JUpiter ICy moons Explorer (JUICE) mission is set to launch in 2022, with expected arrival at Jupiter in 2030.

The European Space Agency’s Herschel Space Observatory (formerly called Far Infrared and Sub-millimetre Telescope or FIRST) has the largest single mirror ever built for a space telescope. At 3.5-metres in diameter the mirror will collect long-wavelength radiation from some of the coldest and most distant objects in the Universe. In addition, Herschel is the only space observatory to cover a spectral range from the far infrared to sub-millimetre.

Source: ESA

Featured image: Don Davis

The view from a fragment of the Shoemaker / Levy 9 comet which fell into Jupiter piece by piece over several days in Late July 1994, around the 25th anniversary of Apollo 11. Acrylic on board for NASA Ames.

Water in Jupiter’s atmosphere came from 1994 comet impact

Related posts:

  1. ScienceCasts: Christmas Sky Show This Christmas, the Moon and Jupiter are converging for a...
  2. Moon, Venus and Jupiter sky show in early morning sky Venus, Jupiter and the moon will gather together in the...

Dust transports over Central Asia and northern China

Thu, 04/25/2013 - 15:34

Interaction of global wind systems at two interconnected deserts in Eastern China - Badain Jaran and Tengger Shamo deserts, are major source of sand and sediments dust transport over Central Asia and northern China.

Tengger Desert covers about 36,700 km2 and is mostly in the Inner Mongolia Autonomous Region in China. The Badain Jaran Desert  spans the provinces of Gansu, Ningxia and Inner Mongolia. It covers an area of 49,000 sq. kilometers (19,000 sq. miles). This desert is home to the tallest stationary dunes on Earth. Some of the dunes reach a height of 500 meters (1,600 ft.). The dunes are kept in place in the arid, windy region by an underground water source. Analyses of the ground water indicates that it is snowmelt that flows through fractured rock from mountains hundreds of kilometers away.

Satellite image shows region of Tengger and Badain Jaran deserts in China on April 25, 2013 (Credit: MODIS/EarthSnapshot)

 

Source: EarthSnapshot

Featured image credit: EarthSnapshot

 

Dust transports over Central Asia and northern China

Related posts:

  1. Dust storm in northern Taklamakan Desert, China A dust storm lifts sand, dirt and other particles into...
  2. Dust and clouds blew over the Taklimakan Desert in western China Dust and clouds blew over the Taklimakan Desert in western...

Active volcanoes in the world: April 17 – April 23, 2013

Thu, 04/25/2013 - 13:39

This week, one volcano had new activity, whereas ongoing activity was reported for 10 volcanoes. This report covers active volcanoes in the world recorded from April 17 – April 23, 2013 based on Smithsonian/USGS criteria.

New activity/unrest: | Soputan, Sulawesi

Ongoing activity: | Batu Tara, Komba Island (Indonesia) | Etna, Sicily (Italy) | Kilauea, Hawaii (USA) | Kizimen, Eastern Kamchatka (Russia) | Manam, Northeast of New Guinea (SW Pacific) | Paluweh, Lesser Sunda Islands (Indonesia) | Rabaul, New Britain | Sakura-jima, Kyushu | Shiveluch, Central Kamchatka (Russia) | Tolbachik, Central Kamchatka (Russia)

The Weekly Volcanic Activity Report is a cooperative project between the Smithsonian’s Global Volcanism Program and the US Geological Survey’s Volcano Hazards Program. Updated by 2300 UTC every Wednesday, notices of volcanic activity posted on these pages are preliminary and subject to change as events are studied in more detail. This is not a comprehensive list of all of Earth’s volcanoes erupting during the week, but rather a summary of activity at volcanoes that meet criteria discussed in detail in the “Criteria and Disclaimers” section. Carefully reviewed, detailed reports on various volcanoes are published monthly in the Bulletin of the Global Volcanism Network.

 

New activity/unrest

 

SOPUTAN, Sulawesi

1.108°N, 124.73°E; summit elev. 1784 m

CVGHM reported that seismicity at Soputan increased during January-18 April and then significantly increased on 19 April. The Alert Level was raised to 3 (on a scale of 1-4) on 19 April. Visitors and residents were prohibited from going within a 6.5-km radius of the crater.

Geologic summary: The small conical volcano of Soputan on the southern rim of the Quaternary Tondano caldera is one of Sulawesi’s most active volcanoes. During historical time the locus of eruptions has included both the summit crater and Aeseput, a prominent NE-flank vent that formed in 1906 and was the source of intermittent major lava flows until 1924.

 

Ongoing activity

 

BATU TARA, Komba Island (Indonesia)

7.792°S, 123.579°E; summit elev. 748 m

Based on analyses of satellite imagery and wind data, the Darwin Volcanic Ash Advisory Centre (VAAC) reported that during 17 and 20-21 April ash plumes from Batu Tara rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 45-55 km N, NW, and W. On 23 April an ash plume rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted 18-27 km NW.

Geologic summary: The small isolated island of Batu Tara in the Flores Sea about 50 km north of Lembata (formerly Lomblen) Island contains a scarp on the eastern side similar to the Sciara del Fuoco of Italy’s Stromboli volcano. Vegetation covers the flanks of Batu Tara to within 50 m of the 748-m-high summit. Batu Tara lies north of the main volcanic arc and is noted for its potassic leucite-bearing basanitic and tephritic rocks. The first historical eruption from Batu Tara, during 1847-52, produced explosions and a lava flow.

 

ETNA, Sicily (Italy)

37.734°N, 15.004°E; summit elev. 3330 m

Sezione di Catania – Osservatorio Etneo reported that the eleventh lava-fountaining episode of 2013 began at Etna’s New Southeast Crater (NSEC) on 18 April. Activity increased on 16 April with ejected incandescent tephra and small ash puffs from a vent inside NSEC, followed by weak Strombolian explosions. Strombolian explosions became more frequent and intense on the morning of 18 April and then were almost continuous by 1300. During the next two hours lava fountains developed and a dense plume drifted SSW. Ash and lapilli fell in between the villages of Ragalna, Belper, and Paterno, as well as the tourist area “Etna Sud.” Lapilli-fall was a few centimeters deep and clasts were at most 5 cm in diameter. Three lava flows were produced; the largest flowed through the deep notch in the SE rim of the crater and traveled 4 km towards the Valle del Bove. The interaction of the lava with snow led to rapid melting, generating small lahars. The two other lava flows originated in the saddle between the two SEC cones; one traveled N and the other S. After the lava fountains ceased, strong explosions were heard the rest of the day. On 19 April explosions produced little puffs of ash and ejected hot tephra.

The twelfth episode occurred two days later during the late afternoon of 20 April. Intermittent explosions ejected incandescent tephra and generated small ash puffs on 19 April. During the evening a large dark plume rose from NSEC, and sporadic Strombolian explosions were observed. The explosive activity ceased in the late evening, but shortly afterwards the lower of the two effusive vents at the base of the NSEC cone produced a lava flow that traveled 1.5 km towards the Valle del Bove. Around 1700 ash puffs rose from the crater, followed by incandescent tephra ejected at 1713. Within a few minutes sustained lava fountains were observed, along with a tall eruption plume that drifted E. Ash and lapilli fell over a wide area to the E, including along the Ionian coastline, just S of Guardia Mangano, up to Fiumefreddo, including the towns of Taormina, Ripon, and Mascali, and further upstream, including Santa Venerina, Zafferana, Milo, and Sant’Alfio.

On 20 April several lava flows on the W wall of the Valle del Bove interacted with the snow, generating explosions and lahars. Around 1815 lava-fountain activity decreased and turned into explosions and ash emissions. At 1840 the paroxysm was over. In the evening, the lava flow emitted from the effusive vent at the base of the SE part of the NSEC cone was still well-fed. Poor weather conditions prevented visual observations until the evening of 21 April, when surveillance videos showed sporadic Strombolian explosions accompanied by small ash puffs at the NSEC, and the emission of a small lava flow from the base of the cone.

Geologic summary: Mount Etna, towering above Catania, Sicily’s second largest city, has one of the world’s longest documented records of historical volcanism, dating back to 1500 BC. Historical lava flows cover much of the surface of this massive basaltic stratovolcano, the highest and most voluminous in Italy. Two styles of eruptive activity typically occur at Etna. Persistent explosive eruptions, sometimes with minor lava emissions, take place from one or more of the three prominent summit craters, the Central Crater, NE Crater, and SE Crater. Flank eruptions, typically with higher effusion rates, occur less frequently and originate from fissures that open progressively downward from near the summit. A period of more intense intermittent explosive eruptions from Etna’s summit craters began in 1995. The active volcano is monitored by the Instituto Nazionale di Geofisica e Volcanologia (INGV) in Catania.

 

KILAUEA, Hawaii (USA)

19.421°N, 155.287°W; summit elev. 1222 m

During 17-23 April HVO reported that the circulating lava lake periodically rose and fell in the deep pit within Kilauea’s Halema’uma’u Crater. The plume from the vent continued to deposit variable amounts of ash, spatter, and Pele’s hair onto nearby areas.

At Pu’u ‘O’o Crater, glow emanated from three spatter cones and a small lava pond on the crater floor. Just before midnight on 19 April a vigorous lava flow gushed out of the N spatter cone and quickly covered the N portion of the crater floor, then went over the E rim. The lava pond on the NE crater’s edge briefly overflowed. On 21 April the two spatter cones on the S portion of the crater floor produced lava flows.

Two lava flows (Peace Day and Kahauale’a) were fed by lava tubes extending from Pu’u ‘O’o. Multiple lava flows from the NE spatter cone, collectively called the Kahauale’a flow, stopped advancing on 20 April, although a few breakout lava flows were observed during 20-22 April. Peace Day activity consisted of lava flows active above the pali (5 km SE of Pu’u ‘O’o), on the pali, and on the coastal plain. Lava also entered the ocean at two or three locations spanning the National Park boundary.

Geologic summary: Kilauea, one of five coalescing volcanoes that comprise the island of Hawaii, is one of the world’s most active volcanoes. Eruptions at Kilauea originate primarily from the summit caldera or along one of the lengthy E and SW rift zones that extend from the caldera to the sea. About 90% of the surface of Kilauea is formed of lava flows less than about 1,100 years old; 70% of the volcano’s surface is younger than 600 years. A long-term eruption from the East rift zone that began in 1983 has produced lava flows covering more than 100 sq km, destroying nearly 200 houses and adding new coastline to the island.

 

KIZIMEN, Eastern Kamchatka (Russia)

55.130°N, 160.32°E; summit elev. 2376 m

KVERT reported that during 12-19 April moderate seismic activity continued at Kizimen. Video and satellite data showed that lava continued to extrude from the summit, producing incandescence, strong gas-and-steam activity, and hot avalanches on the W and E flanks. Satellite images detected a daily thermal anomaly over the volcano. The Aviation Color Code remained at Orange.

Geologic summary: Kizimen is an isolated, conical stratovolcano that is morphologically similar to Mount St. Helens prior to its 1980 eruption. The summit of Kizimen consists of overlapping lava domes, and blocky lava flows descend the flanks of the volcano, which is the westernmost of a volcanic chain north of Kronotsky volcano. The 2,376-m-high Kizimen was formed during four eruptive cycles beginning about 12,000 years ago and lasting 2,000-3,500 years. The largest eruptions took place about 10,000 and 8300-8400 years ago, and three periods of longterm lava-dome growth have occurred. The latest eruptive cycle began about 3,000 years ago with a large explosion and was followed by lava-dome growth lasting intermittently about 1,000 years. An explosive eruption about 1,100 years ago produced a lateral blast and created a 1.0 x 0.7 km wide crater breached to the NE, inside which a small lava dome (the fourth at Kizimen) has grown. A single explosive eruption, during 1927-28, has been recorded in historical time.

 

MANAM, Northeast of New Guinea (SW Pacific)

4.080°S, 145.037°E; summit elev. 1807 m

RVO reported that a high level of activity at Manam continued on 15 April. Ash plumes rose 500 m above the crater. A loud explosion was heard at 0804. At about 1950 dense ash plumes rose 2 km and drifted SW. At night loud jet-like noises were reported by residents in Bogia, 25-30 km SSW of Manam on the N coast of the mainland. Bright red glow was visible within the dense mixture of ash plumes and atmospheric clouds. Lava was observed flowing from a new vent on the headwall of SW valley during a brief clear period from 1800 to 1850. Ash and scoria fell in most villages between Dugulava on the SW side of the island and Kuluguma on the NW side. Similar activity continued during the first half of 16 April and then changed to gentle light gray ash emissions until 20 April. On 23 April dense white vapor plumes occasionally rose from the crater.

Geologic summary: The 10-km-wide island of Manam, lying 13 km off the northern coast of mainland Papua New Guinea, is one of the country’s most active volcanoes. Four large radial valleys extend from the unvegetated summit of the conical 1807-m-high basaltic-andesitic stratovolcano to its lower flanks. These “avalanche valleys,” regularly spaced 90 degrees apart, channel lava flows and pyroclastic avalanches that have sometimes reached the coast. Two summit craters are present; both are active, although most historical eruptions have originated from the southern crater, concentrating eruptive products during much of the past century into the SE avalanche valley. Frequent historical eruptions, typically of mild-to-moderate scale, have been recorded at Manam since 1616. Occasional larger eruptions have produced pyroclastic flows and lava flows that reached flat-lying coastal areas and entered the sea, sometimes impacting populated areas.

 

PALUWEH, Lesser Sunda Islands (Indonesia)

8.32°S, 121.708°E; summit elev. 875 m

Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that on 20 April an ash plume from Paluweh rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 45 km NW.

Geologic summary: Paluweh volcano, also known as Rokatenda, forms the 8-km-wide island of Paluweh N of the volcanic arc that cuts across Flores Island. Although the volcano rises about 3,000 m above the sea floor, its summit reaches only 875 m above sea level. The broad irregular summit region contains overlapping craters up to 900 m wide and several lava domes. Several flank vents occur along a NW-trending fissure. The largest historical eruption of Paluweh occurred in 1928, when a strong explosive eruption was accompanied by landslide-induced tsunamis and lava-dome emplacement.

 

RABAUL, New Britain

4.271°S, 152.203°E; summit elev. 688 m

RVO reported that during 15-23 April white vapor plumes containing some ash rose at most 100 m from Rabaul caldera’s Tavurvur cone and drifted SE. Roaring and rumbling noises were less intense than during previous weeks. Based on analyses of satellite imagery, the Darwin VAAC reported that on 18 April an ash plume rose to an altitude of 4.6 km (15,000 ft) a.s.l. and drifted more than 35 km E. Satellite images later that day showed that the plume had dispersed.

Geologic summary: The low-lying Rabaul caldera on the tip of the Gazelle Peninsula at the NE end of New Britain forms a broad sheltered harbor. The outer flanks of the 688-m-high asymmetrical pyroclastic shield volcano are formed by thick pyroclastic-flow deposits. The 8 x 14 km caldera is widely breached on the E, where its floor is flooded by Blanche Bay. Two major Holocene caldera-forming eruptions at Rabaul took place as recently as 3,500 and 1,400 years ago. Three small stratovolcanoes lie outside the northern and NE caldera rims. Post-caldera eruptions built basaltic-to-dacitic pyroclastic cones on the caldera floor near the NE and western caldera walls. Several of these, including Vulcan cone, which was formed during a large eruption in 1878, have produced major explosive activity during historical time. A powerful explosive eruption in 1994 occurred simultaneously from Vulcan and Tavurvur volcanoes and forced the temporary abandonment of Rabaul city.

 

SAKURA-JIMA, Kyushu

31.585°N, 130.657°E; summit elev. 1117 m

Based on information from JMA, the Tokyo VAAC reported that on 17 April an eruption from Sakura-jima produced an ash plume that rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted E. JMA reported that three large eruptions from Showa Crater occurred during 19-22 April and ejected tephra at most 1.3 km from the crater. Crater incandescence was detected at night.

Geologic summary: Sakura-jima, one of Japan’s most active volcanoes, is a post-caldera cone of the Aira caldera at the northern half of Kagoshima Bay. Eruption of the voluminous Ito pyroclastic flow was associated with the formation of the 17 x 23-km-wide Aira caldera about 22,000 years ago. The construction of Sakura-jima began about 13,000 years ago and built an island that was finally joined to the Osumi Peninsula during the major explosive and effusive eruption of 1914. Activity at the Kita-dake summit cone ended about 4,850 years ago, after which eruptions took place at Minami-dake. Frequent historical eruptions, recorded since the 8th century, have deposited ash on Kagoshima, one of Kyushu’s largest cities, located across Kagoshima Bay only 8 km from the summit. The largest historical eruption took place during 1471-76.

 

SHIVELUCH, Central Kamchatka (Russia)

56.653°N, 161.360°E; summit elev. 3283 m

Based on visual observations and analyses of satellite data, KVERT reported that during 12-19 April a viscous lava flow effused on the NW flank of Shiveluch’s lava dome, accompanied by hot avalanches, incandescence, and fumarolic activity. Satellite imagery showed a daily thermal anomaly on the lava dome. Based on analyses of satellite imagery, the Tokyo VAAC reported that on 22 April ash plumes rose to an altitude of 3.7 km (12,000 ft) a.s.l. and drifted NE. Subsequent images that day showed that the ash had dissipated. The Aviation Color Code remained at Orange.

Geologic summary: The high, isolated massif of Shiveluch volcano (also spelled Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group and forms one of Kamchatka’s largest and most active volcanoes. The currently active Molodoy Shiveluch lava-dome complex was constructed during the Holocene within a large breached caldera formed by collapse of the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large eruptions of Shiveluch have occurred during the Holocene, making it the most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent collapses of lava-dome complexes, most recently in 1964, have produced large debris avalanches whose deposits cover much of the floor of the breached caldera. Intermittent explosive eruptions began in the 1990s from a new lava dome that began growing in 1980. The largest historical eruptions from Shiveluch occurred in 1854 and 1964.

 

TOLBACHIK, Central Kamchatka (Russia)

55.830°N, 160.330°E; summit elev. 3682 m

KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a lava plateau on the SW side of Tolbachik, continued to produce very fluid lava flows during 12-19 April that traveled to the W, S, and E sides of the plateau. Cinder cones continued to grow along the S fissure. Gas-and-ash plumes rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted in multiple directions. A large thermal anomaly on the N part of Tolbachinsky Dol was visible daily in satellite imagery. The Aviation Color Code remained at Orange.

Geologic summary: The massive Tolbachik basaltic volcano is located at the southern end of the dominantly andesitic Kliuchevskaya volcano group. The Tolbachik massif is composed of two overlapping, but morphologically dissimilar volcanoes. The flat-topped Plosky Tolbachik shield volcano with its nested Holocene Hawaiian-type calderas up to 3 km in diameter is located east of the older and higher sharp-topped Ostry Tolbachik stratovolcano. The summit caldera at Plosky Tolbachik was formed in association with major lava effusion about 6500 years ago and simultaneously with a major southward-directed sector collapse of Ostry Tolbachik volcano. Lengthy rift zones extending NE and SSW of the volcano have erupted voluminous basaltic lava flows during the Holocene, with activity during the past two thousand years being confined to the narrow axial zone of the rifts. The 1975-76 eruption originating from the SSW-flank fissure system and the summit was the largest historical basaltic eruption in Kamchatka.

Source: Global Volcanism Program

Featured image: Mike BairdCC BY 2.0

Active volcanoes in the world: April 17 – April 23, 2013

Related posts:

  1. Active volcanoes in the world – April 11 – April 17, 2012 This report covers active volcanoes recorded from April 11 –...
  2. Active volcanoes in the world – April 4 – April 10, 2012 This report covers active volcanoes recorded from April 4 –...

Deadly earthquake and flash floods hit northern Afghanistan

Wed, 04/24/2013 - 15:12

A deadly earthquake magnitude 5.6 (USGS) struck Hindu Kush, northeastern Afghanistan, on April 24, 2013 at 09:25 UTC (13:55 local time). Epicenter was located in Nangarhar province, 11 km (6 miles) S of Mehtar Lam, Afghanistan and 25 km (15 miles) NW of Jalalabad, Afghanistan, at coordinates 34.517°N, 70.207°E. USGS measured depth at 62.1 km.

Pakistan Meteorological Department is reporting M 6.2 at depth of 72 km.

GDACS reported that this earthquake can have a medium humanitarian impact based on the magnitude and the affected population and their vulnerability. There are 7 830 000 people living within 100 km.

Hundreds of homes collapsed across Kunar and Nangarhar. By unofficial numbers there were 25 people killed and 120 are reportedly injured (20:30 UTC). It is past midnight in Afghanistan now (UTC +4:30h), and many people are still believed to be under the rubble. New reports should come about in the morning.

Additionally, flash floods were reported in northern Afghanistan, Balkh province, earlier today, as well as landslides. On Tuesday, April 23rd, heavy rains sent deluges down hillsides of villages in the remote districts of Kishindih, Sholgara and Nahri Shai. National Disaster Management Authority said that steady rain across most of Afghanistan today would have weakened the mud-brick dwellings many Afghans live in (NST). AP photo here.

At least 15 people were killed in flash floods, official reports said today. In its preliminary report, the U.N. said flooding also closed major roads in Balkh.

The map of Afghanistan provinces is here.

Magnitude5.6Date-Time
  • Wednesday, April 24, 2013 at 09:25:29 UTC
  • Wednesday, April 24, 2013 at 01:55:29 PM at epicenter
Location34.517°N, 70.207°EDepth62.1 km (38.6 miles)RegionHINDU KUSH REGION, AFGHANISTANDistances11 km (6 miles) S of Mehtar Lam, Afghanistan
25 km (15 miles) NW of Jalalabad, Afghanistan
66 km (41 miles) NW of Markaz-e Woluswali-ye Achin, Afghanistan
69 km (42 miles) NE of Hukumati Azrow, AfghanistanLocation Uncertaintyhorizontal +/- 10.1 km (6.3 miles); depth +/- 6.1 km (3.8 miles)ParametersNST=267, Nph=405, Dmin=106.9 km, Rmss=0.77 sec, Gp= 22°,
M-type=body wave magnitude (Mb), Version=DSource
  • Magnitude: USGS NEIC (WDCS-D)
    Location: USGS NEIC (WDCS-D)
Event IDusb000geu9

 

Regional seismicity

Earthquakes in Hindu Kush and broader region are common and occur as a result of the collision of the India and Eurasia continental plates. Indian subcontinent is moving northward at a rate of about 40 mm/yr (1.6 inches/yr) and colliding with the Eurasian continent. Underthrusting of India beneath Eurasia generates numerous earthquakes and consequently makes this area one of the most seismically hazardous regions on Earth. This collision is causing uplift that produces the highest mountain peaks in the world including the Himalayan, the Karakoram, the Pamir and the Hindu Kush ranges.

The worst earthquake to hit Afghanistan in recent years occurred on May 30, 1998. A 6.9 magnitude earthquake struck Takhar and Badakhshan provinces. Between 4,000 and 4,500 people died.

As a result of this same tectonic collisions on October 8, 2005, a magnitude 7.6 earthquake and a series of aftershocks struck Kashmir near the city of Muzaffarabad, Pakistan. It left nearly 75,000 people dead, injured more than 100,000 people, and destroyed 3 million homes. That earthquake actually split the Earth’s surface in an event geologists call a surface rupture. This surface rupture extended for 75 kilometers (47 miles). Robert Yeats, a geologist at Oregon State University, concluded after traveling to Pakistan that in the known historic and recent records, not one of the earthquakes in the Himalaya has ever produced a surface rupture, not in Nepal, or India, or anywhere. This rupture was the first one (EO). In some areas, the earthquake shifted the ground more than 5 meters (16 feet).

Muzaffarabad sits at the boundary between the slowly colliding Indian and Eurasian tectonic plates, both composed of thick continental crust. The pressure of the collision isn’t released gradually, but suddenly, when rocks that can no longer bear the stress crack. These forces make Kashmir one of the most earthquake-prone regions on Earth. (NASA map by Robert Simmon, from CleanTOPO2 data.)

Tectonic summary by USGSSeismotectonics of the Himalaya and Vicinity

… The India-Eurasia plate boundary is a diffuse boundary, which in the region near the north of India, lies within the limits of the Indus-Tsangpo (also called the Yarlung-Zangbo) Suture to the north and the Main Frontal Thrust to the south. The Indus-Tsangpo Suture Zone is located roughly 200 km north of the Himalaya Front and is defined by an exposed ophiolite chain along its southern margin. The narrow (<200km) Himalaya Front includes numerous east-west trending, parallel structures. This region has the highest rates of seismicity and largest earthquakes in the Himalaya region, caused mainly by movement on thrust faults. Examples of significant earthquakes, in this densely populated region, caused by reverse slip movement include the 1934 M8.1 Bihar, the 1905 M7.5 Kangra and the 2005 M7.6 Kashmir earthquakes. The latter two resulted in the highest death tolls for Himalaya earthquakes seen to date, together killing over 100,000 people and leaving millions homeless. The largest instrumentally recorded Himalaya earthquake occurred on 15th August 1950 in Assam, eastern India. This M8.6 right-lateral, strike-slip, earthquake was widely felt over a broad area of central Asia, causing extensive damage to villages in the epicentral region.

The Tibetan Plateau is situated north of the Himalaya, stretching approximately 1000km north-south and 2500km east-west, and is geologically and tectonically complex with several sutures which are hundreds of kilometer-long and generally trend east-west. The Tibetan Plateau is cut by a number of large (>1000km) east-west trending, left-lateral, strike-slip faults, including the long Kunlun, Haiyuan, and the Altyn Tagh. Right-lateral, strike-slip faults (comparable in size to the left-lateral faults), in this region include the Karakorum, Red River, and Sagaing. Secondary north-south trending normal faults also cut the Tibetan Plateau. Thrust faults are found towards the north and south of the Tibetan Plateau. Collectively, these faults accommodate crustal shortening associated with the ongoing collision of the India and Eurasia plates, with thrust faults accommodating north south compression, and normal and strike-slip accommodating east-west extension. Read the rest of tectonic summary here.

Featured image: Hindu Kush range by Michal Hvorecky

 

Deadly earthquake and flash floods hit northern Afghanistan

Related posts:

  1. Afghanistan dust storm A dense cloud of dust swept across southern Afghanistan and...
  2. Crop failure compounds drought crisis in Afghanistan Ongoing drought in northern, northeastern and western Afghanistan is likely...

Strong earthquake M 6.5 struck New Ireland Region, Papua New Guinea

Tue, 04/23/2013 - 23:27

A strong earthquake M 6.5 struck New Ireland Region, Papua New Guinea on Tuesday, April 23, 2013 at 23:14:42 UTC. Epicenter of the earthquake was located 30 km (18 miles) N of Rabaul, Papua New Guinea and 50 km (31 miles) NNW of Kokopo, Papua New Guinea at coordinates 3.911°S, 152.127°E. Earthquake’s depth was recorded at 16.3 km (USGS). EMSC reported same magnitude at depth of 47 km.

GDACS estimates this earthquake can have a low humanitarian impact based on the Magnitude and the affected population and their vulnerability.

There are about 250000 people within 100 km radius of the earthquake.

 

Magnitude6.5Date-Time
  • Tuesday, April 23, 2013 at 23:14:42 UTC
  • Wednesday, April 24, 2013 at 09:14:42 AM at epicenter
Location3.911°S, 152.127°EDepth16.3 km (10.1 miles)RegionNEW IRELAND REGION, PAPUA NEW GUINEADistances30 km (18 miles) N of Rabaul, Papua New Guinea
50 km (31 miles) NNW of Kokopo, Papua New Guinea
209 km (129 miles) SE of Kavieng, Papua New Guinea
284 km (176 miles) NE of Kimbe, Papua New GuineaLocation Uncertaintyhorizontal +/- 14.8 km (9.2 miles); depth +/- 5.2 km (3.2 miles)ParametersNST=100, Nph=100, Dmin=31.2 km, Rmss=0.61 sec, Gp= 25°,
M-type=(unknown type), Version=ASource
  • Magnitude: USGS NEIC (WDCS-D)
    Location: USGS NEIC (WDCS-D)
Event IDusb000gen8

Intensity shakemap of the earthquake. Credits: USGS

Tectonic Summary by USGSSeismotectonics of the New Guinea Region and Vicinity

The Australia-Pacific plate boundary is over 4000 km long on the northern margin, from the Sunda (Java) trench in the west to the Solomon Islands in the east. The eastern section is over 2300 km long, extending west from northeast of the Australian continent and the Coral Sea until it intersects the east coast of Papua New Guinea. The boundary is dominated by the general northward subduction of the Australia plate.

Along the South Solomon trench, the Australia plate converges with the Pacific plate at a rate of approximately 95 mm/yr towards the east-northeast. Seismicity along the trench is dominantly related to subduction tectonics and large earthquakes are common: there have been 13 M7.5+ earthquakes recorded since 1900. On April 1, 2007, a M8.1 interplate megathrust earthquake occurred at the western end of the trench, generating a tsunami and killing at least 40 people. This was the third M8.1 megathrust event associated with this subduction zone in the past century; the other two occurred in 1939 and 1977.

Further east at the New Britain trench, the relative motions of several microplates surrounding the Australia-Pacific boundary, including north-south oriented seafloor spreading in the Woodlark Basin south of the Solomon Islands, maintain the general northward subduction of Australia-affiliated lithosphere beneath Pacific-affiliated lithosphere. Most of the large and great earthquakes east of New Guinea are related to this subduction; such earthquakes are particularly concentrated at the cusp of the trench south of New Ireland. 33 M7.5+ earthquakes have been recorded since 1900, including three shallow thrust fault M8.1 events in 1906, 1919, and 2007.

The western end of the Australia-Pacific plate boundary is perhaps the most complex portion of this boundary, extending 2000 km from Indonesia and the Banda Sea to eastern New Guinea. The boundary is dominantly convergent along an arc-continent collision segment spanning the width of New Guinea, but the regions near the edges of the impinging Australia continental margin also include relatively short segments of extensional, strike-slip and convergent deformation. The dominant convergence is accommodated by shortening and uplift across a 250-350 km-wide band of northern New Guinea, as well as by slow southward-verging subduction of the Pacific plate north of New Guinea at the New Guinea trench. Here, the Australia-Pacific plate relative velocity is approximately 110 mm/yr towards the northeast, leading to the 2-8 mm/yr uplift of the New Guinea Highlands.

Whereas the northern band of deformation is relatively diffuse east of the Indonesia-Papua New Guinea border, in western New Guinea there are at least two small (<100,000 km²) blocks of relatively undeformed lithosphere. The westernmost of these is the Birds Head Peninsula microplate in Indonesia’s West Papua province, bounded on the south by the Seram trench. The Seram trench was originally interpreted as an extreme bend in the Sunda subduction zone, but is now thought to represent a southward-verging subduction zone between Birds Head and the Banda Sea.

There have been 22 M7.5+ earthquakes recorded in the New Guinea region since 1900. The dominant earthquake mechanisms are thrust and strike slip, associated with the arc-continent collision and the relative motions between numerous local microplates. The largest earthquake in the region was a M8.2 shallow thrust fault event in the northern Papua province of Indonesia that killed 166 people in 1996.

The western portion of the northern Australia plate boundary extends approximately 4800 km from New Guinea to Sumatra and primarily separates Australia from the Eurasia plate, including the Sunda block. This portion is dominantly convergent and includes subduction at the Sunda (Java) trench, and a young arc-continent collision.

In the east, this boundary extends from the Kai Islands to Sumba along the Timor trough, offset from the Sunda trench by 250 km south of Sumba. Contrary to earlier tectonic models in which this trough was interpreted as a subduction feature continuous with the Sunda subduction zone, it is now thought to represent a subsiding deformational feature related to the collision of the Australia plate continental margin and the volcanic arc of the Eurasia plate, initiating in the last 5-8 Myr. Before collision began, the Sunda subduction zone extended eastward to at least the Kai Islands, evidenced by the presence of a northward-dipping zone of seismicity beneath Timor Leste. A more detailed examination of the seismic zone along it’s eastern segment reveals a gap in intermediate depth seismicity under Timor and seismic mechanisms that indicate an eastward propagating tear in the descending slab as the negatively buoyant oceanic lithosphere detaches from positively buoyant continental lithosphere. On the surface, GPS measurements indicate that the region around Timor is currently no longer connected to the Eurasia plate, but instead is moving at nearly the same velocity as the Australia plate, another consequence of collision.

Large earthquakes in eastern Indonesia occur frequently but interplate megathrust events related to subduction are rare; this is likely due to the disconnection of the descending oceanic slab from the continental margin. There have been 9 M7.5+ earthquakes recorded from the Kai Islands to Sumba since 1900. The largest was the great Banda Sea earthquake of 1938 (M8.5) an intermediate depth thrust faulting event that did not cause significant loss of life.

 

Featured image: EMSC + Google maps

Strong earthquake M 6.5 struck New Ireland Region, Papua New Guinea

Related posts:

  1. Strong earthquake M 6.5 struck Papua New Guinea Strong earthquake M 6.5 struck New Britain Region, Papua New...
  2. Very strong earthquake M 6.6 hit Bougainville region, Papua New Guinea A very strong earthquake magnitude 6.6 hit Bougainville region, Papua New...

The growing threat of space debris

Tue, 04/23/2013 - 16:50

There is a continuing increase in space debris that poses a growing threat to economically vital orbital regions. Many experts like satellite operators around the world, including those flying telecom, weather, navigation, broadcast and climate-monitoring missions, are putting their efforts on controlling space debris.

Since the beginning of the space age there have been almost 5000 launches by all spacefaring nations.The result of that is a lot of human-made space debris of which about two-thirds originate from orbital break-ups – more than 240 explosions – and fewer than 10 known collisions.

In 2009 a collision between America’s Iridium-33 civil communications satellite and Russia’s Kosmos-2251 military satellite demolished both and produced a large amount of debris – more than 2200 tracked fragments.

Scientists evaluate the level of space debris in Earth’s orbit to be around 29 000 objects bigger than 10 cm, 670 000 pieces bigger than 1 cm, and more than 170 million above 1 mm.

Heiner Klinkrad, Head of ESA’s Space Debris Office, said that any of these objects can harm an operational spacecraft.

Klinkrad pointed out that satellite collisions with fragments above 10 cm would be catastrophic releasing hazardous debris clouds that can lead to further catastrophic collisions that may produce increasing debris in some orbits.

Space debris mitigation measures, if properly implemented by satellite designers and mission operators, can curtail the growth rate of the debris population. Active debris removal, however, has been shown to be necessary to reverse the debris increase, Klinkrad explained.

The ultimate aim is to prevent collisional cascading from happening over the next few decades.

According to Thomas Reiter, Director of Human Spaceflight and Operations, this is a global task, active removal is a challenge that should be undertaken by joint efforts in cooperation with the world’s space agencies and industry.

Reiter added that ESA, as a space technology and operations agency, has identified the development of active removal technologies as a strategic goal.

The 6th European Conference on Space Debris is taking place at ESOC, ESA’s European Space Operations Centre, Darmstadt,Germany (April 22–25, 2013).

Source: ESA

Featured image credit: Fraunhofer FHR

The growing threat of space debris

No related posts.

Solar missions to observe comet ISON (How to track ISON on SOHO and STEREO imagery)

Mon, 04/22/2013 - 23:20

Comet ISON is on a journey through our solar system that will culminate in its close encounter with the Sun on November 28, 2013. At that time the comet will pass at a distance of only 2.7 solar radii from the Suns center.

Comet C/2012 S1, named ISON, was discovered in September 2012 by Russian astronomers Vitali Nevski and Artyom Novichonok using data from the International Scientific Optical Network (ISON).Because ISON was discovered relatively early, beyond the orbit of Jupiter, and will fly so close to the Sun, many have high hopes that it could turn out to be a major comet.

An observing campaign is set in motion by a number of solar missions, including SOHO and STEREO, to observe the comet as it passes near the Sun. SOHO’s LASCO C2 and C3 coronagraphs are expected to have a view of C/2012 S1 as it passes through their fields-of-view, as presented below.

Predicted hour-by-hour position of Comet ISON in the LASCO C3 (blue) and C2 (red) fields-of-view on SOHO, November 27-30, 2013. (Credit: SOHO)

 

As for SOHO, the comet will enter its viewpoint from the lower right early on November 27, 2013 and will exit towards the top near the end of November 30, 2013.

The first STEREO telescope to get a view of Comet ISON will be the large angle Heliospheric Imager #2 on the Ahead spacecraft (HI2-A). In the first image below we can see the projected day-by-day location of the comet in the HI2-A field-of-view from October 10, 2013, when it is supposed to enter on the left side of the field, through November 23, 2013, when it is expected to exit on the right side of the field. On the right image is the comet’s passage through the smaller HI1-A field-of-view November 21-28, 2013.

Predicted day-by-day position of Comet ISON in the HI2-A field-of-view from October 10, 2013 on the left, to November 23, 2013 on the right.Predicted day-by-day position in the HI1-A field-of-view from November 21-28, 2013, moving from left to right.

 

The two STEREO spacecrafts are expected to have a view of the comet in the COR1 and COR2 coronagraphs in the hours around closest approach on November 28, 2013.

In both cases, the comet enters from the lower left and exits close to the top of the image. The coronagraphs on STEREO Ahead are supposed to be able to see ISON for about a day and half between about 04:00 UTC on November 28, 2013 and 14:00 UTC on November 29, 2013. The Behind coronagraphs are expected to have a longer look at the comet, from about 06:00 UTC on November 26 until the end of the day on November 29, 2013.

Throughout the period when Comet ISON is nearest to the Sun, it will actually pass in front of the Sun as seen from Behind. This gives us a chance that we could possibly see extreme-ultraviolet emission from the comet, as was seen recently with the bright sungrazing Comet Lovejoy.

Predicted hour-by-hour position of Comet ISON in the COR2-A (blue) and COR1-A (green) fields-of-view between 04:00 UTC on November 28,2013 and 14:00 UTC on November 29 ,2013. Predicted hour-by-hour position of Comet ISON in the COR2-B (blue), COR1-B (green), and EUVI-B (orange) fields-of-view between 06:00 UTC on November 26, 2013 and 00:00 UTC on November 30, 2013.

 

After ISON swings around the Sun, it passes once again through the HI1-A field-of view throughout the first week in December, as presented below. At this time, the comet is leaving at such a steep angle that the nucleus never passes through the HI2-A field-of-view without rolling the spacecraft, though there is a chance that a tail might be visible.

SOHO’s LASCO C2 and C3 coronagraphs are expected to have a view of the comet as it passes through their fields-of-view, as shown below. From SOHO’s viewpoint the comet enters from the lower right early on November 27, 2013 and exits towards the top near the end of November 30, 2013 (Credit: SOHO)

 

The trajectory information presented here is based on preliminary estimates of Comet ISON’s orbit. With more observations of the comet collected, these orbital estimates will be refined, and improved over time.

 

Sources: SOHO, STEREO

Featured image: Predicted position of Comet ISON in the EUVI-B field-of-view in ten-minute intervals between 18:10 UTC and 20:10 UTC on November 28, 2013. (Credit: STEREO)

Solar missions to observe comet ISON (How to track ISON on SOHO and STEREO imagery)

Related posts:

  1. Comet ISON could become Comet of the Century NASA’s  Scientific Visualization Studio released another excellent video of  Comet ISON (C/2012...
  2. Real facts about comet Elenin statement by Leonid Elenin SpaceObs, website run by Leonid Elenin, the most mysterious amateur...

Old Faithful’s hidden cavern discovered

Mon, 04/22/2013 - 18:12

A new study of the Yellowstone National Park geyser shows that the underground plumbing of the Old Faithful looks like a bagpipe. Scientists report, in study published online March 30, 2013 in the journal Geophysical Research Letters, that a big chamber is positioned about 15 meters (50 feet) underground, located southwest of Old Faithful.

The research presents another strong argument against the long-standing idea that big geysers erupt from long, narrow tubes. The researchers who uncovered new evidence of a chamber suspect that it stores the pressurized near-boiling water, steam, and other gases that propel Old Faithful’s eruptions

Old Faithful got its name because of its regular eruptions, which occur every 92 minutes on average. Almost immediately after an eruption, there’s a 15-minute recharge period with low water levels. After that for about 50 minutes, water levels rise and seismic activity increases. The cavern never fully empties, but as steam bubbles fill it, they can oscillate water in the conduit, eventually producing a strong steam explosion. This bubble trap is what makes Old Faithful splash with smaller eruptions before releasing its full force.

 

The graph of Old Faithful Geyser  shows the estimated shape of a subterranean cavity beneath the geyser (Credit: GeoSpace )

 

The egg-shaped cavern is least 15 m (50 feet) tall and 18 m (60 feet) wide, although its size can’t be precisely determined. It is connected to a pipe at the angle of about 24 degrees that feeds Old Faithful’s maw. Now, for the first time, experts have a clear picture of the underground workings of The Old Faithful.

Using tiny tremors extracted from seismic records collected in the 1990s researchers were able to reveal the shape of the void and geyser conduit. Additionally, the tremors can also track water.

Jean Vandemeulebrouck, a geophysicist at the University of Savoie in France, said that they were able to locate with one- to two-meter precision the place where the boiling occurs, and that they can see the water rising in the conduit.

Photograph of the Old Faithful Geyser erupting in Yellowstone National Park. Old Faithful was named in 1870 during the Washburn-Langford-Doane Yellowstone expedition and was the first geyser in the Park to be named. (Source: USGS)

 

Scientists working in Kamchatka’s Valley of the Geysers concluded that those Russian geysers also erupted from conduits fed by caverns. They also found out that the geysers explode because of underground bubble traps, as is with Old Faithful.

There are only about 1,000 geysers around the world. For the formation of the geyser, there must be plentiful groundwater, a volcanic heat source to warm the water, open spaces so the water can escape and a way to trap bubbles.

Vandemeulebrouck, in collaboration with the U.S. Geological Survey, is now studying another Yellowstone National Park geyser, called Lone Star, and the preliminary results they acquired are similar to Old Faithful. His opinion is that this oscillating system is quite common in geysers.

 

Sources: Geophysical Research LettersGeoSpace,

Featured image: Scientist have found a chamber beneath Old Faithful that might help fuel its predictable eruptions. (Credit: Barbara Richman/American Geophysical Union)

Old Faithful’s hidden cavern discovered

Related posts:

  1. Yellowstone earthquake activity remains at background levels On Sunday, October 7, 2012 a small earthquake swarm occurred...
  2. Yellowstone geysers became active again According to article published in YellowstoneGate a handful of Yellowstone National Park...

Solar Dynamics Observatory: Three Years of Sun in Three Minutes

Mon, 04/22/2013 - 13:24

In the three years since it first provided images of the sun in the spring of 2010, NASA’s Solar Dynamics Observatory (SDO) has had virtually unbroken coverage of the sun’s rise toward solar maximum, the peak of solar activity in its regular 11-year cycle. This video shows those three years of the sun at a pace of two images per day.
SDO’s Atmospheric Imaging Assembly (AIA) captures a shot of the sun every 12 seconds in 10 different wavelengths. The images shown here are based on a wavelength of 171 Angstroms, which is in the extreme ultraviolet range and shows solar material at around 600,000 Kelvin. In this wavelength it is easy to see the sun’s 25-day rotation as well as how solar activity has increased over three years.

During the course of the video, the sun subtly increases and decreases in apparent size. This is because the distance between the SDO spacecraft and the sun varies over time. The image is, however, remarkably consistent and stable despite the fact that SDO orbits the Earth at 6,876 miles per hour and the Earth orbits the sun at 67,062 miles per hour.

Such stability is crucial for scientists, who use SDO to learn more about our closest star. These images have regularly caught solar flares and coronal mass ejections in the act, types of space weather that can send radiation and solar material toward Earth and interfere with satellites in space. SDO’s glimpses into the violent dance on the sun help scientists understand what causes these giant explosions — with the hopes of some day improving our ability to predict this space weather.

There are several noteworthy events that appear briefly in this video. They include the two partial eclipses of the sun by the moon, two roll maneuvers, the largest flare of this solar cycle, comet Lovejoy, and the transit of Venus. The specific time for each event is listed below, but a sharp-eyed observer may see some while the video is playing.

00:30;24 Partial eclipse by the moon

00:31;16 Roll maneuver

01:11;02 August 9, 2011 X6.9 Flare, currently the largest of this solar cycle

01:28;07 Comet Lovejoy, December 15, 2011

01:42;29 Roll Maneuver

01:51;07 Transit of Venus, June 5, 2012

02:28;13 Partial eclipse by the moon

 

More information about this video, as well as full HD version of all four wavelengths and print-resolution stills are public domain and can be viewed and downloaded at: http://svs.gsfc.nasa.gov/vis/a010000/…

Video credit: NASA SDO

Featured image credit: This image, is a composite of 25 separate images spanning the period of April 16, 2012 to April 15, 2013. It uses the SDO AIA wavelength of 171 Angstroms and reveals the zones on the sun where active regions are most common during this part of the solar cycle. This version maintains the original aspect ratio of the AIA instrument imagery. Credit: NASA’s Goddard Space Flight Center/SDO/S. Wiessinger

Solar Dynamics Observatory: Three Years of Sun in Three Minutes

Related posts:

  1. SDO’s 2013 solar spring eclipse season has begun NASA’s Solar Dynamics Observatory (SDO) has eclipse seasons twice a...
  2. “It’s a Loopy Sun” by NASA/SDO NASA/SDO released a short video which covers January 5 through...

Pages

Drupal theme by pixeljets.com D7 ver.1.1