As Seen from Space: Ghostly, Ethereal Island

The volcanic island Ostrov Shikotan as seen by The Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite.

[/caption]

Looking rather otherworldly, this haunting view of Shikotan-to island shows ghostly swirls of sea ice surrounding the snow-covered volcanic island. Also known as Ostrov Shikotan, this island is at the southern end of a volcanic archipelago called the Kuril Chain, which is part of the Pacific Ring of Fire. The chain stretches approximately 1,300 km (810 mi) northeast from Japan, off the coast of Russia. The Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite captured this natural-color image of Shikotan on February 14, 2011.

When the ice around the island forms, it is shaped by the moving currents – giving it a swirly appearance. North of the western end of Shikotan, eddies have shaped the ice into rough circles.

The island’s rugged appearance comes from millions of years of volcanic and seismic activity, multiple tsunamis, and weathering from wind and rain. The total land area of Shikotan is 225 square km.

Although this island is a part of Russia, Japan maintains a claim to it as well. And although you wouldn’t guess it from this image, there are two different settlements of about 1,000 people each. The name of Shikotan derives from an ancient Japanese dialect and means “land with big communities.”

See a larger version of the image at NASA’s Earth Observatory website.

Spectacular ATV Kepler Launch Photo Captured from Orbiting ISS

This remarkable photo was taken by ESA astronaut Paolo Nespoli from the ISS on 16 February 2011, just minutes after ATV Johannes Kepler lifted off on board an Ariane 5 from Kourou at 22:50 UTC. It shows the rising exhaust trail of Ariane, still in its initial vertical trajectory. The trail can be seen as a thin streak framed just beneath the Station's remote manipulator arm. Credits: ESA/ NASA

[/caption]

Have you ever seen a space launch from orbit ?

Check out the spectacular launch photo (above) of the Johannes Kepler ATV streaking skyward atop an Ariane 5 rocket as captured by astronaut Paolo Nespoli from his unparalleled vantage point looking out the windows aboard the International Space Station (ISS), in orbit some 350 km above Earth.

The launch photo shows the rising exhaust trail from the rocket just minutes after blast off of the Ariane booster on Feb. 16 from the ESA rocket base in Kourou, French Guiana, South America. The rocket was still on a vertical ascent trajectory to orbit. Additional launch photos below from space and Earth.

Photo captured on 16 February 2011 from the real-time video from the Ariane 5 launcher during the flight V200 during the time of jettisoning the boosters.

The photo vividly illustrates the maturity of the European space effort since the launch base, Ariane booster rocket, Kepler payload and astronaut Nespoli all stem from Europe and are crucial to the future life of the ISS.

Ariane 5 rocket at the Launch pad at Europe's Spaceport in Kourou, French Guiana with Johannes Kepler ATV bolted on top prior to Feb. 16 blast off.

Kepler is set to dock at the ISS on Feb. 24 and an on time arrival is essential because of an impending orbital traffic jam.

Space Shuttle Discovery is due to link up with the ISS just six hous after Kepler if the orbiter launches according to schedule on Feb. 22.

Everything is nominal with Kepler’s spacecraft systems and orbital performance at this time say European Space Agency (ESA) officials, including the deployment of ATV’s four large solar wings.

Ariane 5 liftoff with Johannes Kepler ATV

The ATV, or Automated Transfer Vehicle, is a European built resupply vessel designed to transport essential cargo and provisions to the ISS. It is Europe’s contribution to stocking up the ISS.

Kepler is carrying carries more than seven metric tons of supplies and cargo for the ISS and will be used to reboost the outpost to a higher orbit during its planned four month mission.

“ATV is a truly European spacecraft. Flying it requires experts from ESA, partner agencies and industry across half a dozen countries,” said ESA’s Bob Chesson, Head of the Human Spaceflight Operations Department.

“Getting it built, into orbit and operating it in flight to docking requires a lot of hard work and dedication from hundreds of people.”

The ATV is named after Johannes Kepler (1571-1630), the German astronomer and mathematician who is best known for discovering the laws of planetary motion. NASA also named its powerful new planet hunting space telescope after Kepler, which recently discovered the first earth sized planets orbiting inside the habitable zone.

After the shuttle is forcibly retired later this year in 2011, the very survival and continued use of the ISS will be completely dependent on a steady train of cargo and payloads lofted by unmanned resupply vessels including the ATV from Europe, HTV from Japan, Progress from Russia and commercial carriers such as SpaceX and Orbital Sciences.

Photos of Ariane rockets rising exhaust trail from Feb. 16 ATV launch photographed from the ISS. Credits: ESA/ NASA

European Space Agency (ESA) astronaut Paolo Nespoli, Expedition 26 flight engineer, conducts a test run with the French/CNES neuroscientific research experiment 3D-Space (SAP) in the Columbus laboratory of the International Space Station.

Gallery: WISE’s Greatest Hits

WISE First Light image. Image credit: NASA/JPL-Caltech/UCLA

[/caption]

The WISE mission is now over, with the spacecraft taking its final image on Feb. 1, 2011. WISE was a “cool” infrared mission, with the optics chilled to less than 20 degrees centigrade above absolute zero (20 Kelvins). In its low Earth orbit (523 km above the ground), the spacecraft explored the entire Universe and collected infrared light coming from everywhere in space and studied asteroids, the coolest and dimmest stars, and the most luminous galaxies. Expect to hear and see more from WISE, however in the future. More images will be released from the team in April and in the spring of 2012. Here’s a look back at some of the great images from WISE’s 13 months in space:

The red dot at the center of this image is the first near-Earth asteroid discovered by NASA's Wide-Field Infrared Survey Explorer, or WISE Image credit: NASA/JPL-Caltech/UCLA
The red smudge at the center of this picture is the first comet discovered by NASA's Wide-Field Infrared Survey Explorer, or WISE. Image credit: NASA/JPL-Caltech/UCLA
The immense Andromeda galaxy, also known as Messier 31 or simply M31, is captured in full in this February 2010 image from WISE. credit: NASA/JPL-Caltech/UCLA
NGC 3603, as seen by WISE. credit: NASA/JPL-Caltech/UCLA
NGC 1514, sometimes called the Crystal Ball nebula shows a new double ring feature in an image from WISE. Image credit: NASA/JPL-Caltech/UCLA
This image from WISE shows the Tadpole nebula. Image credit: NASA/JPL-Caltech/UCLA
The Heart and Soul nebulae are seen in this infrared mosaic from WISE. Image credit: NASA/JPL-Caltech/UCLA
An image released in August 2010 from WISE image of the Small Magellanic Cloud. Image credit: NASA/JPL-Caltech/WISE Team
This oddly colorful nebula is the supernova remnant IC 443 as seen by WISE. Image credit: NASA/JPL-Caltech/UCLA
The last image that will ever be taken by the WISE spacecraft. Credit: NASA/JPL-Caltech/WISE Team

And if you want to see how it all started, here’s a video of WISE’s launch:

Mysterious Noctilucent Clouds As Seen from Space

Polar mesospheric clouds (PMCs) observed by the Ozone Monitoring Instrument (OMI) on the Aura satellite. Maps by Robert Simmon. Credit: NAS

[/caption]

Mysterious “night shining” or noctilucent clouds are beautiful to behold, and are usually seen during the summertime, appearing at sunset. They are thin, wavy ice clouds that form at very high altitudes and reflect sunlight long after the Sun has dropped below the horizon. Scientists don’t know exactly why they form, but continue to observe them – both from Earth and from space. These images were taken by the Ozone Monitoring Instrument (OMI) on NASA’s Aura satellite.

Also called polar mesospheric clouds, they are puzzling scientists with their recent dramatic changes. They used to be considered rare, but now the clouds are growing brighter, are seen more frequently, are visible at lower and lower latitudes than ever before, and — as these satellite image reveal — they are now even appearing during the day.

Noctilucent clouds over Kendal Castle, England in June 2010. Credit: Stuart Atkinson

Noctilucent clouds form in an upper layer of the Earth‘s atmosphere called the mesosphere during the Northern Hemisphere’s summer – at an altitude of 80 km (50 miles). They can start forming as early as May, and extend through August. They can also be seen in high latitudes during the summer months in the Southern Hemisphere.

What could the observed changes mean? Some scientists believe they are a good gauge of even the tiniest changes in the atmosphere, as they are extremely sensitive to changes in atmospheric water vapor and temperature. The clouds form only when temperatures drop below -130 degrees Celsius (-200 Fahrenheit), when the scant amount of water high in the atmosphere freezes into ice clouds.

Scientist Matthew DeLand of Science Systems and Applications Inc. and NASA’s Goddard Space Flight Center has been monitoring polar mesospheric clouds with instruments that were actually designed to study ozone, including the OMI, which provides more detailed and frequent observations than previous instruments. This gives DeLand a way to refine his previous measurements of a long-term trend towards more and brighter noctilucent clouds linked to rising greenhouse gases.

These images at the top of this article show OMI measurements of polar mesospheric clouds on July 10, 2007. The clouds, detectable because they are the only things that reflect light in this part of the atmosphere, are shown in white and pink. The Aura satellite travels in a polar orbit, circling from south to north as the Earth turns beneath it. As a result, the satellite gets several opportunities to image the poles every day. This series of images shows the clouds over six consecutive orbits between 7:16 and 15:52 Universal Time. Throughout the day, a wide area of polar mesospheric clouds developed over northern Greenland and Canada, peaking around 10:30 UTC (the third orbit).

Another instrument observing these clouds is the Solar Backscatter Ultraviolet (SBUV) instruments, which have flown on seven different satellites over the past 32 years, and that wealth of data is showing how the clouds change throughout the day.

DeLand now has an index to help correct the SBUV measurement trends to account for the time of day. The correction allows him to develop a more accurate view of the long-term trend. Even with the corrections, the trend indicates that the atmosphere has been responding to increased greenhouse gases over the past 30 years.

The fact that polar mesospheric clouds are getting brighter suggests that the mesosphere is getting colder and more humid, says DeLand. Increasing greenhouse gases in the atmosphere could account for both phenomena.

Sources: NASA Earth Observatory, twice

How To See NanoSail-D From Your Own Backyard

Artist concept of Nanosail-D in Earth orbit. Credit: NASA

[/caption]

The night sky has many wonderful objects to look at on a clear evening, including many man-made satellites, and the always impressive International Space Station (ISS). Now there’s a new addition to these artificial delights: the first ever solar sail to orbit the Earth, NASA’s Nanaosail-D Satellite. Want to know how you can see it?

The 10m x 10m reflective sail is designed to act like a brake and gradually create drag in the upper atmosphere, slowly pulling a satellite down and de-orbiting it at the end of its working life. Nanosail-D is testing the potential of this technology to reduce space junk and debris.

NanoSail D. Image credit NASA

The satellite has a huge reflective sail and could potentially be many times brighter than the planet Venus when it catches a glint from the Sun. Unlike the International Space Station (ISS) and other satellites, the sail will not be visible when it is directly above us as we will be looking at it edge on, It will be more visible when closer to the horizon.

The Nanosail-D satellite will be visible from now and for the next few months. To see it you will need to know exactly when it will be visible from your location. To do this, go to heavens-above.com or spaceweather.com where star charts with times and pass details will be displayed after you enter your observing site.

Once you know the time and location in the sky of the pass of the satellite, make sure you are able to get a good view of the horizon, or part of the sky where the satellite due to appear. Give yourself plenty of time, go outside and get ready. I always set a 30 second reminder on my watch or cell phone, so I don’t have to fumble around or guess the time.

Unlike the ISS and most other satellites, Nanosail-D passes may only last a few, or a few tens of seconds, so make sure you are looking in the right place at the right time. You will see an amazingly bright star-like object rise up, get brighter and then suddenly disappear. When it “disappears” it is still passing over, it’s just no longer at the right angle or is no longer being illuminated by the sun. NanoSail-D has few reflective surfaces compared to many on the ISS.

To enjoy the Nanosail-D passes:

• Make sure you know the right place in the sky and the time of the pass, by checking on the web.
• Make sure you will be able to get a clear view of it from your viewing location.
• Set an alarm or get ready for the pass as it only lasts a few seconds.
• NASA expects NanoSail-D to stay in orbit until April or May 2011.
• If you are an astrophotographer, don’t forget, NASA and SpaceWeather.com are having an imaging contest of NanoSail-D. Find out more here.
• Most of all, get your friends and family outside with you to watch Nanosail-D and enjoy!

Videos: Two Different Satellite Views of the Big Snowstorm of 2011

Here's an image from the top animation, the storm as seen on January 31, 2011

To speak in the vernacular of the peasantry, this storm was a whopper. Heavy snow, ice, freezing rain, and frigid wind battered about two thirds of the United States, making it “a winter storm of historic proportions,” said the National Weather Service. This animation—made with images from the NOAA-NASA GOES 13 satellite—shows the giant storm developing and moving across the country between January 31 and February 2. Below is another video view from GOES-East satellite, which includes infrared water vapor imagery from January 29 -February 1, 2011.

And there’s also an update on Cyclone Yasi.

[/caption]

Cyclone Yasi as seen on Feb. 1, 2011 from The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite

Yasi weakened after coming ashore early on Thursday morning but was still strong enough to produce high winds and tidal surges that sent waves crashing deep into seaside communities. Thankfully, so far no lives have been lost because of this storm. Officials said lives were saved because after days of dire warnings people heeded directions to flee to evacuation centers or bunker themselves at home. Track the storm on WeatherUnderground, and read more on the latest news from Yasi on The Guardian.

Sources: NASA Earth Observatory, SolarWatcher, The Guardian

Satellite View: Huge Storm Heads Across the US

The GOES-13 satellite captured this image on Jan. 31, 2011 of a major winter storm covering a large portion of the US. Image Credit: NOAA/NASA GOES Project

[/caption]

The roads are a skating rink where I live! This visible image was captured by the GOES-13 satellite on January 31, 2011 and it shows the low pressure area bringing snowfall to the Midwest US. Heavy snow is expected today in portions of northern Iowa, southern Minnesota and Wisconsin. Snowfall from the system extends from Michigan west to Montana, Idaho, Utah and Arizona. A mix of rain and snow also stretches into the Ohio and Tennessee valleys, and it is all moving east. This system appears to be as large as 1/3rd of the Continental U.S.

Meanwhile, in another hemisphere on the other side of the world a huge tropical cyclone threatens parts of Australia that has already been suffering from flooding.

of Tropical Cyclone Yasi taken at 6:29 a.m. PST (9:29 a.m. EST) on Jan. 31, 2011. Areas colored purple represent the storm's coldest cloud-top temperatures and areas of heaviest precipitation. Image credit: NASA/JPL-Caltech

The northeastern Australian state of Queensland is now bracing for what could become one of the largest tropical cyclones the state has ever seen.

The Atmospheric Infrared Sounder (AIRS) instrument on NASA’s Aqua satellite captured this infrared image of Yasi on Jan. 31, 2011, at 6:29 a.m. PST (9:29 a.m. EST). The AIRS data create an accurate 3-D map of atmospheric temperature, water vapor and clouds, data that are useful to forecasters. The image shows the temperature of Yasi’s cloud tops or the surface of Earth in cloud-free regions.

The coldest cloud-top temperatures appear in purple, indicating towering cold clouds and heavy precipitation. The infrared signal of AIRS does not penetrate through clouds. Where there are no clouds, AIRS reads the infrared signal from the surface of the ocean waters, revealing warmer temperatures in orange and red.

At the approximate time this image was taken, Yasi had maximum sustained winds near 90 knots (166 kilometers per hour, or 103 mph), equivalent to a Category Two hurricane on the Saffir-Simpson Scale. It was centered about 1,400 kilometers (875 miles) east of Cairns, Australia, moving west at about 19 knots per hour (35 kilometers per hour, or 22 mph). Cyclone-force winds extend out to 48 kilometers (30 miles) from the center.

Yasi is forecast to move west, then southwestward, into an area of low vertical wind shear (strong wind shear can weaken a storm). Forecasters at the Joint Typhoon Warning Center expect Yasi to continue to strengthen over the next 36 hours. The Center forecasts a landfall just south of Cairns as a large 100-plus knot-per-hour (185 kilometers per hour, or 115 mph) system by around midnight local time on Wednesday, Feb. 2.

Sources: JPL, NASA Earth Observatory

It’s Alive! NanoSail-D Suddenly and Spontaneously Comes Back to Life

Artist concept of Nanosail-D in Earth orbit. Credit: NASA

[/caption]

A small solar sail that was thought to be a lost cause has “spontaneously” come back to life. The NanoSail-D — a NASA-designed solar sail cubesat that launched in December but suddenly went silent without confirmation of its deployment — unexpectedly ejected from its host satellite on Wednesday, Jan. 19 at 11:30 a.m. EST. Engineers at Marshall Space Flight Center confirmed that the NanoSail-D nanosatellite ejected from Fast Affordable Scientific and Technology Satellite, FASTSAT, when they looked at onboard FASTSAT telemetry. The ejection of NanoSail-D also has been confirmed by ground-based satellite tracking.

Now NASA is asking for help from ham radio operators to listen for the signal to verify NanoSail-D is operating. And knowing the status of the solar sail is time critical.

“This is great news for our team. We’re anxious to hear the beacon which tells us that NanoSail-D is healthy and operating as planned,” said Dean Alhorn, NanoSail-D principal investigator and aerospace engineer at the Marshall Center. “The science team is hopeful to see that NanoSail-D is operational and will be able to unfurl its solar sail.”

If you are a ham operator, This information should be sent to the NanoSail-D dashboard at: http://nanosaild.engr.scu.edu/dashboard.htm. The NanoSail-D beacon signal can be found at 437.270 MHz. You can learn more at the MSFC’s Ham Radio Operator’s webpage.

NanoSail-D was designed to test the potential for solar sails in atmospheric braking. On December 6, 2010, it was schedule to eject from the FASTSAT, and initially it looked as though it did. But later, ground controllers were unable to confirm if the solar sail had ejected or deployed. Further analysis showed no evidence of NanoSail-D in low-Earth orbit, leading the team to believe NanoSail-D remained inside FASTSAT.

Now, with this latest news that the loaf-of-bread-sized satellite has ejected on its own, the NanoSail-D science team is hopeful the nanosatellite is healthy and can complete its solar sail mission. But the sequence of events are time critical.

After ejection, a timer within NanoSail-D begins a three-day countdown as the satellite orbits the Earth. Once the timer reaches zero, four booms will quickly deploy and the NanoSail-D sail will start to unfold to a 100-square-foot polymer sail. Within five seconds the sail fully unfurls.

“We knew that the door opened and it was possible that NanoSail-D could eject on its own,” said Mark Boudreaux, FASTSAT project manager at the Marshall Center. “What a pleasant surprise this morning when our flight operations team confirmed that NanoSail-D is now a free flyer.”

If the deployment is successful, NanoSail-D will stay in low-Earth orbit between 70 and 120 days, depending on atmospheric conditions. NanoSail-D is designed to demonstrate deployment of a compact solar sail boom system that could lead to further development of this alternative solar sail propulsion technology and FASTSAT’s ability to eject a nano-satellite from a micro-satellite — while avoiding re-contact with the FASTSAT satellite bus.

Source: Marshall Space Flight Center

Can China enter the international space family?

China has become only the third nation in the world to have a manned space program. Photo: Chine

[/caption]

It has often been called a ‘100 billion boondoggle’ – yet it is also unquestionably one of the most successful international programs in human history. The International Space Station (ISS) is just now starting to produce some of the valuable science that was the station’s selling point from the beginning. However, this delay can be attributed to the numerous tragedies, economic woes and other issues that have arisen on a global scale through the course of the station’s construction.

The one thing that the world learned early on from the ISS experience is that space is a great forum for diplomacy. One time arch-rivals now work side by side on a daily basis.

With much of the nations of the world talking about stepped-up manned exploration efforts it would seem only natural that the successful model used on the space station be incorporated into the highly-expensive business of manned space exploration. If so, then one crucial player is being given a hard look to see if they should be included – China.

Will we one day see Chinese taikonauts working alongside U.S. astronauts and Russian cosmonauts? Only time will tell. Photo Credit: NASA

“International partnership in space exploration has proven its worth over the last decade. It would be a positive step if the other space-faring nation of the world, China, were to join the assembled space explorers of humankind as we march outward into the solar system,” said former NASA Space Shuttle Program Manager Wayne Hale who writes a popular blog about space matters.

China is only the third nation (behind Russia and the United States) to have a successful manned space program, having launched its first successful manned space flight in 2003. This first mission only had a single person onboard, and gave the world a new word – ‘taikonaut’ (taikong is the Chinese word for space). The country’s next mission contained two of these taikonauts and took place in 2005. The third and most current manned mission that China has launched was launched in 2008 and held a crew of three.

Yang Liwei became the first of China's Taikonaut when he rocketed into orbit in 2003. Photo Credit: Xinhua

China has steadily, but surely, built and tested capabilities essential for a robust manned space program. Considering that China very ambitious goals for space this would seem a prudent course of action. China has stated publically that they want to launch a space station and send their taikonauts to the moon – neither of which are small feats.

China currently utilizes its Shenzhou spacecraft atop the Long March 2F booster from their Jiuquan facility. However, if China wants to accomplish these goals, they will need a more powerful booster. This has been part of the reason that the U.S. has been hesitant to include China due to concerns about the use of what are known as dual-use technologies (rockets that can launch astronauts can also launch nuclear weapons).

Both China's rocket and spacecraft are derived from Soviet Soyuz designs. Photo Credit: Xinhua/Wang Jianmin

Some have raised concerns about the nation’s human rights track record. It should be noted however that Russia had similar issues before being included in the International Space Station program.

“In the early 1990’s, some at NASA thought having Russian cosmonauts on the Space Shuttle would mean giving away trade secrets to the competition,” said Pat Duggins, author of the book Trailblazing Mars. “It turned out Russian crew capsules saved the International Space Station when the Shuttles were grounded after the Columbia accident in 2003. So, never say never on China, I guess.”

Duggins is not the only space expert who feels that China would make a good companion when mankind once again ventures out past low-Earth-orbit.

“One of the findings of the Augustine Commission was that the international framework that came out of the ISS program is one of the most important. It should be used and expanded upon for use in international beyond-LEO human space exploration,” said Dr. Leroy Chiao a veteran of four launches and a member of the second Augustine Commission. “My personal belief is that countries like China, which is only the third nation able to launch astronauts, should be included. My hope is that the politics will align soon, to allow such collaboration, using the experience that the US has gained in working with Russia to bring it about.”

Not everyone is completely convinced that China will be as valuable an asset as the Russians have proven themselves to be however.

“It is an interesting scenario with respect to the Chinese participation in an international effort in space. The U.S. has made some tremendous strides in terms of historical efforts to bridge the gap with the Russians and the results have been superb,” said Robert Springer a two-time space shuttle veteran. “The work that has resulted in the successful completion of the International Space Station is an outstanding testimony to what can be done when political differences are set aside in the interest of International cooperation. So, there is a good model of how to proceed, driven somewhat by economic realities as well as politics. I am not convinced that the economic and political scenario bodes well for similar results with the Chinese. It is a worthwhile goal to pursue, but I am personally not convinced that a similar outcome will be the result, at least not in the current environment.”

China's journey into space has just begun, but it remains to be seen if they will be going it alone or as part of a partnership. Photo Credit: Xinhua

Palette Earth: Recent Artwork As Seen From Space

Phytoplankton bloom off of the Atlantic coast of Patagonia on December 21, 2010. NASA image created by Norman Kuring, Ocean Color Web. Instrument: Aqua - MODIS

[/caption]

The view from space of our home planet is often breathtaking and sobering. Lately, there has been a plethora of amazing images on NASA’s Earth Observatory website. Take the one above, for example. A swirling Van Gogh painting? No, phytoplankton blooming off of the Atlantic coast of Patagonia, and the swirls are created from two strong ocean currents stirring up a colorful brew of floating nutrients and microscopic plant life. Amazing that the tiny life joins together in huge assemblages that we can see from space. This image was taken on the southern hemisphere’s summer solstice on December 21, 2010. Scientists used seven separate different spectral bands to highlight the differences in the plankton communities across this swath of ocean.

Want more Earthly beauty? See below.

Tidal flats and channels in the Bahamas. Credit: NASA, astronaut photography from the ISS.

A giant dried rose laying across the ocean? No, this astronaut photograph provides a view of tidal flats and channels near Sandy Cay, on the western side of Long Island and along the eastern margin of the Great Bahama Bank. The continuously exposed parts of the island are brown, a result of soil formation and vegetation growth. To the north of Sandy Cay, an off-white tidal flat composed of carbonate sediments is visible; light blue-green regions indicate shallow water on the tidal flat. The tidal flow of seawater is concentrated through gaps in the land surface, leading to the formation of relatively deep channels that cut into the sediments. The channels and areas to the south of the island have a vivid blue color that indicates deeper water.

Antarctic icebergs. Credit: NASA; Instrument: EO-1 - ALI

While those of us in the northland have had long nights, Antarctica enjoys round-the-clock sunlight. The light arrives at a low angle, however, as the Sun makes a daily circuit around the horizon, and icebergs cast long shadows over the surrounding sea ice. This image, acquired on December 13, 2010, from the Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite shows icebergs along the Princess Ragnhild Coast in East Antarctica. Besides distinguishing between icebergs and thinner ice, the low-angled Sun highlights the differences between the icebergs themselves.

The icebergs with rough surfaces likely broke off from the coast, far from this area, and spent time bobbing over the open ocean. Smooth icebergs likely originated in this area and have not yet traveled far.

For more great images, see NASA’s Earth Observatory website.