Posted on by Nancy Atkinson

Break Up of Antarctic Ice Shelf

If anyone is denial about climate change possibly occuring on Earth, please take a look at this. This animation highlights the rapid loss of ice recently on the Wilkins Ice Shelf in Antarctica. Between February 28 and 29, 2008 an area of about 400 sq km disintegrated into large and small icebergs within 24 hours. As a result of the recent collapse, the remaining shelf, which totals about 14 500 sq km, is now only supported by a 6 km strip of ice. This strip is already rifted, and the remaining strip is in danger of breaking up as well.

The Wilkins Ice Shelf is a broad plate of floating ice south of South America on the Antarctic Peninsula. Since the ice shelf is already floating, this event will not cause a rise in sea level. However, ice shelves on the Antarctic Peninsula are sandwiched by extraordinarily raising surface air temperatures and a warming ocean, making them important indicators for on-going climate change.
Credits: ESA - M. Braun, Bonn University, Center for Remote Sensing of Land Surfaces
Thousands of years of accumulated and compacted snow on the Antarctic central plateau have formed a mighty ice sheet which flows under gravity towards the coastal plane. Along the coast the ice gradually floats on the sea – to form massive ledges known as ice shelves. But as the temperature has increased, several ice shelves have broken up and disintegrated.

The images used for this annimation were taken by the ESA’s Envisat satellite. Within days of its launch, Envisat captured the disintegration of the Larsen-B ice shelf in Antarctica on 18 March 2002. Scientists estimate Larsen-B had been stable since the last ice age 12,000 years ago.

These images were acquired as part of ESA’s support to the International Polar Year (IPY) 2007-2008, a large worldwide science programme focused on the Arctic and Antarctic.

Original News Source: ESA Press Release

Posted on by Nancy Atkinson

Planet Formation Revealed?

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One of the biggest unresolved questions of planet formation is how a thick disc of debris and gas surrounding young stars eventually evolves into a thin, dusty region with planets. This entire process, of course, has never actually been observed. But recently, and for the first time, a group of astrophysicists produced an image of material surrounding a star which seems to be coalescing into a planet.

The image was produced from a coronagraph attached to a telescope in Hawaii. It shows a horseshoe-shaped void in the disc of materials surrounding the star AB Aurigae, with a bright point appearing as a dot in the void.

“The deficit of material could be due to a planet forming and sucking material onto it, coalescing into a small point in the image and clearing material in the immediate surroundings,” said researcher Ben Oppenheimer, an astrophysicist at the American Museum of Natural History in New York. “It seems to be indicative of the formation of a small body, either a planet or a brown dwarf.”

A brown dwarf is considered a star that’s not massive enough to generate the thermonuclear fusion to create an actual star.

From what we know about planet formation, planets seem to be natural by-product of stars. But how does all this happen? Stars form when clouds of gas and dust contract under gravity, and if there’s enough compression and heat, sooner or later a nuclear reaction is triggered, and voilà: a star. If there’s any left-over material surrounding the young star, eventually the disc of dust and/or gas may congeal into planets. But the details of this process are unknown.

AB Aurigae is a well-studied star. It’s young, between one and three million years old, and can provide information on how stars and objects that orbit them form. And scientists hope that by studying this star, we can learn more about how planets form from the initial thick, gas-rich disk of debris that surrounds young stars. The observation of stars slightly older than AB Aurigae shows that at some point the gas is removed, but no one knows how this happens. AB Aurigae could be in an intermediate stage, where the gas is being cleared out from the center, leaving mainly dust behind.

“More detailed observations of this star can help solve questions about how some planets form, and can possibly test competing theories,” says Oppenheimer. And if this object is a brown dwarf, our understanding of them must be revamped as brown dwarfs are not believed to form in circumstellar materials, Oppenheimer said.

Original New Source: National Science Foundation Press Release

Posted on by Nancy Atkinson

Endeavour and Crew Back Home Safely (Video)

After 16 days in space and 250 orbits of the Earth, space shuttle Endeavour touched down at Wednesday evening at NASA’s Kennedy Space Center in Florida, bringing the STS-123 mission to a flawless end. The mission launched in darkness on March 11, and returned home with a rare night landing – and both were spectacular sights. For those of you keeping score at home, Endeavour’s main gear touchdown took place at 8:39:08 p.m. EDT at a mission elapsed time of 15 days, 18 hours, 10 minutes and 55 seconds.

Endeavour lands. Image credit: NASA
Mission managers said the crew was in good health and spirits. “I got to talk to the crew, and the crew was just having a fantastic time reflecting on their mission and looking up at their vehicle that just landed,” said Shuttle Launch Director Mike Leinbach. “They were glad to be home, very proud of the work they did, and we’re very proud of the work they did, too.”

On board Endeavour were Mission Specialists Takao Doi of the Japan Aerospace Exploration Agency, Robert L. Behnken, and Rick Linnehan; Pilot Gregory H. Johnson; Commander Dominic Gorie; and Mission Specialist Mike Foreman, as well as European Space Agency astronaut Léopold Eyharts, who returned to Earth aboard Endeavour after almost 50 days in space on the International Space Station. The 16 day mission was one of the longest space shuttle missions, with 5 spacewalks for station construction that included attaching a Japanese Pressurized Module and putting together Dextre, a robotic handyman that will be available to assist in station construction and maintenence tasks.

If you missed seeing the landing last night, here’s a link to video from NASA

Posted on by Nancy Atkinson

Alan Stern Resigns From NASA

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Alan Stern has stepped down as NASA’s Associate Administrator for the Science Mission Directorate. No word on Stern’s reasons for leaving, or why such an abrupt departure, but the timing suggests it could be related to the erroneous announcement that funding for the Mars Rovers would be cut. Stern is seemingly highly respected and very popular among mission scientists and designers, and Stern had pledged to toe the line about mission spending and cost overruns. There are conflicting reports whether Stern will continue as Principal Investigator for the New Horizons mission to Pluto, but it would be very surprising to see him leave the mission to which he has devoted most of his career.

Stern had only been with the Science Mission Directorate for about a year but during that year Time Magazine named Stern as one of the 100 Most Influential People in 2007.

Continue reading “Alan Stern Resigns From NASA”

Posted on by Nancy Atkinson

XCOR: Economy Class Space Tourism?

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XCOR Aerospace has thrown its hat into the space tourism ring, unveiling its two-seat suborbital spaceship, the Lynx. With its first flights scheduled for 2010, XCOR’s projected price per ticket will be half of what other suborbital companies like Virgin Galactic and Rocketplane are charging. But the Lynx’s flight will also be about half the duration and about two-thirds the altitude of the other companies. At $100,000, a seat on the Lynx is not exactly cheap, but its possible this lower price could cause a price war with the other space tourism companies, which is good news for anyone considering taking a suborbital flight.

“XCOR’s mission is to radically lower the cost of spaceflight, because affordable access to space for everyone means far more than breathtaking views and the freedom of weightlessness,” said XCOR CEO Jeff Greason.

The spaceship, roughly the size of a small private airplane, will be capable of flying several times each day. The Lynx will carry a pilot and one passenger at twice the speed of sound to about 60 km (37 miles) above the Earth. The entire flight would last about a half an hour, with 2 minutes of zero gravity. It will take off and land like an airplane at a conventional airport, and use clean-burning, fully reusable, liquid-fuel rocket engines to reach Mach 2.

“We have designed this vehicle to operate much like a commercial aircraft. Its liquid fuel engines will provide the enhanced safety, durability, reliability and maintainability that keep operating costs low,” said Greason. “These engines will also minimize the impact of these flights on the environment. They are fully reusable, burn cleanly, and release fewer particulates than solid fuel or hybrid rocket motors.”

“Lynx will be the ‘Greatest Ride Off Earth,’” said XCOR test pilot, former NASA astronaut and Space Shuttle commander, Col. Rick Searfoss. “The acceleration, the weightlessness, and the view will provide you with an experience that is out of this world. And the best part of it all is that you’ll ride right up front, like a co-pilot, instead of in back, like cargo.”

Here’s XCOR’s You Tube video for a preview of what the flight will be like:

XCOR also announced that the company has won Small Business Innovation Research (SBIR) Phase II contract with the US Air Force to develop and test operationally responsive features of one of the firm’s commercial vehicles.

For more about XCOR.

Original News Source: XCOR Press Release

Posted on by Nancy Atkinson

Time Traveling With Spitzer

While time travel is seemingly impossible, we can actually look back in time with our telescopes to learn about the conditions of our universe in times past. The Spitzer Space Telescope has found some very dim and distant galaxies located at the edge of our universe that have never been seen before. Approximately 12.5 billion light-years away from Earth, we’re seeing these galaxies as when our universe was just one billion years old. With Spitzer’s infrared capability, astronomers have been able to take infrared portraits and even “weigh” many of these early galaxies. “Understanding the mass and chemical makeup of the universe’s first galaxies and then taking snapshots of galaxies at different ages, gives us a better idea of how gas, dust and metals– the material that went into making our Sun, solar system, and Earth –has changed throughout the Universe’s history,” said Spitzer scientist Dr. Ranga Ram Chary.

Unlike the galaxies of today, Chary says that galaxies living in the one billion year old universe were much more pristine. They were comprised primarily of hydrogen and helium gas and contained less than 10% of the heavier elements we see in the local Universe today, and even on Earth. Astronomers have found these distant galaxies were cosmic “lightweights”, or not very massive compared to mature galaxies we see nearby.

“A few billion years after the big bang, 90 percent of the stars being born were occurring in these types of faint galaxies. By identifying this population, we hope to gain insights into the environments where the universe’s first stars formed,” said Chary.

To find these faint galaxies, astronomers followed the lingering afterglow of gamma ray bursts back to their sources. Astronomers believe gamma ray bursts appear when a very massive star dies and becomes a black hole.

The afterglow occurs when energetic electrons spiral around magnetic fields, and release light. In its explosive death, material shooting out of the massive star smashes into surrounding gas. This violent collision heats nearby gas and energizes its electrons.

Once coordinates of the faint galaxies were determined, Chary’s team then used Spitzer’s supersensitive infrared array camera to snap a picture of the faint galaxy. The amount of light from the galaxies allowed Chary to find the mass of the galaxies.

Original News Source: Spitzer Space Telescope Press Release

Posted on by Nancy Atkinson

Award Winning Images from the STS-123 Gallery

The images coming down from the STS-123 mission have been nothing short of spectacular. The pictures have included amazing EVA shots, images of the astronauts hard at work (and having fun, too) and stunning photos of the ever-growing International Space Station. Here are just a few of the latest images from the mission, and they’re all so great, I’ve decided to give each one an award. This one gets the award for Best Group Photo Ever of the Shuttle, ISS and Earth. On Monday, shuttle Endeavour undocked from the ISS, and after the obligatory fly-around, the astronauts snapped this picture as the shuttle separated from the station. In my mind, this is one of the most amazing images from space ever. And there’s more….

ISS. Image Credit: NASA

This image gets the award for Best Color Contrast Image of the ISS. Backdropped by the airglow of Earth’s horizon and the blackness of space, the ISS hangs on Earth’s limb. What an awesome view that must be live and in person.

Moon shot. Image Credit: NASA

Obviously, this image gets the Best Moon Photo for the STS-123 Mission. Talk about being in the right place at the right time! Framed by different components of the International Space Station, a full moon is visible in this view above Earth’s horizon and airglow. I’d like to give credit where credit is due and say which astronaut snapped this image, but NASA only says the picture was taken by an STS-123 crewmember who was on the station while Space Shuttle Endeavour was docked with the ISS.

STS 123 Aurora

This has to be one of the Best Aurora Picture Ever Taken From Space. I’m still trying to wrap my brain around having the chance to look down to see an aurora. The Aurora Borealis glows beautifully green in this images that looks northward across the Gulf of Alaska, over a low pressure area (cloud vortex). This image was taken on March 21, 2008 at 09:08:46 (GMT) with a 28 mm lens from the nadir point of 47.9 degrees north latitude and 146.8 degreees west longitude.

STS 123 & Station Crews. Image Credit: NASA
Let’s give a round of applause for the crews of STS-123 and the ISS who accomplished so much during the mission with five EVA’s, adding the Japanese Logistics Module to the station and constructing Dextre the robot handyman. Plus they are responsible for all the great images from the mission, too. Shuttle Endeavor will attempt to land on Wednesday, March 26 at 7:05:08 p.m EDT. As of now, the weather looks good for landing in Florida.

Pictured are Russian cosmonaut Yuri Malenchenko, US astronauts Greg Johnson, Rick Linnehan, Garrett Reisman, Dom Gorie, Peggy Whitson, Mike Foreman, Bob Behnken, European astronaut Leopold Eyharts, and Japanese astronaut Takeo Doi.

See all the images from the STS-123 mission here.

Posted on by Nancy Atkinson

Dextre vs. HAL

As Endeavour departs from the International Space Station on Monday, the space shuttle crew leaves behind a two-armed robot, the Special Purpose Dexterous Manipulator (SPDM), which the astronauts affectionately refer to as Dextre. Any reference to robots in space brings to mind other famous, albeit fictitious, machines that have interacted with humans on board a spacecraft. And, with the recent passing of science fiction writer Arthur C. Clarke, one famous machine named HAL particularly comes to mind, especially when you factor in that Dextre is what’s called a “telemanipulator.” Any chance the space station crew needs to worry about the robot lurking right outside their hatch?

Endeavour crewmember Rick Linnehan said, don’t worry, there is no comparison between Dextre and HAL, the famous malfunctioning computer who killed astronauts in the 1968 movie “2001: A Space Odyssey.”

“I’m a big Arthur C. Clarke fan and I have to tell you Dextre just isn’t as smart as HAL,” said Linnehan in new conference from the ISS on Sunday. “He’s built to be brawn not brains and he’s going to serve a big purpose up here in terms of moving a lot of hardware around.”

HAL 9000. Image credit: Wikipedia

Dextre, the two-armed, $200-million robot will reduce the amount of time astronauts must spend outside the space station, and could eliminate the need for up to a dozen spacewalks a year, said Daniel Rey, head of the Canadian technical team that prepared Dextre for his mission on board the space station.

“He will free up astronauts so they can do more science and more research rather than maintenance,” said Rey. Dextre will perform exterior construction and tasks like changing batteries and handling experiments outside the space station. Dextre also comes equipped with a tool holster which allows the robot to change equipment as needed “like any good handyman.”

Rey also concurred that 3.7-meter robot Dextre can’t be compared to HAL. “He doesn’t have an artificial intelligence. . .he can be remote controlled from the ground or from the space station.” Dextre will be able to manipulate items “from the size of a phone book to a phone booth,” Rey added.

As for HAL, in the movie “2001: A Space Odyssey,” he maintains all systems on an interplanetary voyage, plays chess, and has a special penchant for lip reading. Those capabilities just aren’t in Dextre’s database. However, HAL was programmed with the objective to ensure mission success. That’s one area where HAL and Dex do have something in common.

Original News Source: NASA TV and the Canadian Press

Posted on by Nancy Atkinson

Does a Boomerang Work in Space?

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Testing a boomerang in space might look and sound trivial, but it’s an exciting physics experiment that helps scientists to understand the dynamics of flight in microgravity. And now, one aspect of the “boomerang in space” question has finally been tested and answered. Japanese astronaut Takao Doi “threw a boomerang and saw it come back” during his free time on March 18 at the International Space Station, said a spokeswoman for the Japan Aerospace Exploration Agency. “I was very surprised and moved to see that it flew the same way it does on Earth,” the 53-year-old Doi was quoted as saying. This test was done inside a pressurized module of the ISS. But, one big question about boomerangs in space remains:

Will it work in the vacuum of space?

No, says boomerang expert and designer Gary Broadbent. The boomerang that was used in the experiment on board the ISS was a design of Broadbent’s called a “Roomerang,” a small, tri-blade boomerang intended for use indoors in a small area or outdoors in light winds. It travels 5 to 8 feet before returning to the thrower.

Broadbent told Universe Today that a boomerang would not work in the vacuum of space. “You need air molecules to generate the lift to make the boomerang turn,” Broadbent said.

But he also added that in the pressurized environment of the ISS, “microgravity has very little effect on the boomerang flight. The boomerang is so versatile, it can be tuned to fly in a perfect path back to the thrower, with gyroscopic precession and angular momentum over-compensating the lack of gravity.”
space boomerang. Image courtesy of Gary Broadbent

Doi decided on boomerang tests after he received a request from Yasuhiro Togai, a world boomerang champion who helped Doi train to throw a boomerang correctly. Broadbent said that he has part of the preparations as well, and has been to Florida 3 times in the past month, working on the experiment with Doi.

The wings of a boomerang are set at a slight tilt and they have an airfoil design (rounded on one side and flat on the other, just like an airplane wing), which gives the wing lift.

The uneven force caused by the difference in speed between the three wings (two wings on a regular boomerang) applies a constant force which forces the boomerang to turn. So, just as if you lean in one direction while riding a bicycle, and the bike turns in that direction, the boomerang is constantly turning with force in one direction, so that it travels in a circle and comes back to its starting point.

Even though Broadbent says boomerangs wouldn’t work in a vacuum, it still would be fun to test it. The only problem of doing this experiment out in space is that the boomerang would just become another piece of potentially dangerous space junk in Earth orbit.

A videotape of the experiment performed during the STS-123 mission will likely be released in the near future.

Original News Source: Physorg.com and email interview with Gary Broadbent. For more information on Broadbent’s Boomerang’s see Gary’s website

Posted on by Nancy Atkinson

Delays For Shuttle Program?

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With the current shuttle mission going so well, this news is a little depressing. Future space shuttle missions may be delayed because a backlog of work is developing on external fuel tanks for the shuttles. The tank used by Endeavour for the current mission was the last in the inventory of ET’s built before the 2003 Columbia disaster. The next shuttle flight, scheduled for late May, will use the first of the new design of tanks that include improvements to help eliminate foam shedding. But production issues with subsequent tanks may force delays for future missions, including Atlantis’ STS-125 mission to service the Hubble Space Telescope, currently targeted for August 28. If the delays amount to more than a couple of months, it’s possible the Hubble could give out before the shuttle could get there because of failing batteries and gyroscopes.

Since for the Hubble mission, the shuttle wouldn’t be going to the International Space Station, there would be no safe haven option for Atlantis’ crew if major heat shield damage occurs. The station and Hubble are in different orbits and the shuttle does not have the ability to move from one to the other. As a result, NASA approved plans to have a second shuttle, Endeavour, ready for launch on a rescue mission just in case.

That means NASA needs two ready-to-fly external tanks for the Hubble mission. One should be ready, no problem, but the second one is the issue. Manpower and production issues are the main problems. The people at Michoud had to redo much of the work on existing fuel tanks, and then they took a direct hit from Hurricane Katrina in 2005. Some workers moved elsewhere, and the program has not been at peak production since. Additional unplanned work has also caused delays, such as the upgrade to the fuel sensors that plagued the last shuttle tank, used for the STS-122 mission.

For now, the Hubble mission remains officially scheduled for August 28, but some sources say the mission could be delayed to October. More on this as the picture becomes clearer and the story develops.

Original News Source: CBS News Space Place