Behind the Power and Beauty of Northern Lights

Northern Lights. Credit: NASA

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The Aurora Borealis or Northern Lights are stunningly beautiful. But they can also disrupt radio communications and GPS signals, and even cause power outages. What’s behind the ethereal Northern Lights that causes them to shimmer and dance with colorful lights while sometimes wreaking havoc with electrical systems here on Earth? Using a fleet of five satellites, NASA researchers have discovered that explosions of magnetic energy a third of the way to the moon power substorms that cause sudden brightenings and rapid movements of the aurora borealis, called the Northern Lights. “We discovered what makes the Northern Lights dance,” said Dr. Vassilis Angelopoulos of the University of California, Los Angeles. Angelopoulos is the principal investigator for the Time History of Events and Macroscale Interactions during Substorms mission, or THEMIS.

The cause of the shimmering in Northern Lights is magnetic reconnection, a common process that occurs throughout the universe when stressed magnetic field lines suddenly snap to a new shape, like a rubber band that’s been stretched too far.

“As they capture and store energy from the solar wind, the Earth’s magnetic field lines stretch far out into space. Magnetic reconnection releases the energy stored within these stretched magnetic field lines, flinging charged particles back toward the Earth’s atmosphere,” said David Sibeck, THEMIS project scientist at NASA’s Goddard Space Flight Center. “They create halos of shimmering aurora circling the northern and southern poles.”

An explosion of energy increases in the brightness and movement of Northern Lights. Credit: NASA/Goddard Space Flight Center
An explosion of energy increases in the brightness and movement of Northern Lights. Credit: NASA/Goddard Space Flight Center

The data was gathered by five strategically positioned Themis satellites, combined with information from 20 ground-based observatories located throughout Canada and Alaska. Launched in February 2007, the five identical satellites line up once every four days along the equator and take observations synchronized with the ground observatories. Each ground station uses a magnetometer and a camera pointed upward to determine where and when an auroral substorm will begin. Instruments measure the auroral light from particles flowing along Earth’s magnetic field and the electrical currents these particles generate.

See animation of magnetic reconnection.

During each alignment, the satellites capture data that allow scientists to precisely pinpoint where, when, and how substorms measured on the ground develop in space. On Feb. 26, 2008, during one such THEMIS lineup, the satellites observed an isolated substorm begin in space, while the ground-based observatories recorded the intense auroral brightening and space currents over North America.

These observations confirm for the first time that magnetic reconnection triggers the onset of substorms. The discovery supports the reconnection model of substorms, which asserts a substorm starting to occur follows a particular pattern. This pattern consists of a period of reconnection, followed by rapid auroral brightening and rapid expansion of the aurora toward the poles. This culminates in a redistribution of the electrical currents flowing in space around Earth.

Solving the mystery of where, when, and how substorms occur will allow scientists to construct more realistic substorm models and better predict a magnetic storm’s intensity and effects.

More about Themis.

Original News Source: NASA press release

Unusual Exoplanet Dances in Sync With Its Sun-Like Star

Artist's impression of COROT. Credit: ESA

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The European Space Agency’s COROT spacecraft has discovered an unusual exoplanet orbiting a star slightly more massive than our Sun. The planet, currently called COROT-exo-4b, is about the same size as Jupiter, and it takes 9.2 days to orbit its star. Most peculiar however, is that the planet and the star are in sync: the star rotates at the same pace as the planet’s period of revolution. Astronomers feel the planet is too low in mass and too distant from the star for the star to have any major influence on the planet’s rotation. But they are trying to understand the special interaction between this star and planet.

COROT stands for Convection, Rotation and planetary Transits. Launched in 2006, the mission has now observed more than 50,000 stars. The spacecraft is designed to detect rocky exoplanets almost as small as Earth. The satellite uses transits, the tiny dips in the light output from a star when a planet passes in front of it, to detect and study planets. This is followed up by extensive ground-based observations.

COROT-exo-4b is the fifth exoplanet found by the COROT spacecraft. Monitoring continuously over several months, the team tracked variations in its brightness between transits. They derived its period of rotation by monitoring dark spots on its surface that rotated in and out of view. It takes 9.2 days for the planet to orbit its star, which so far, is the longest period for any transiting exoplanet ever found.

It is not known whether COROT-exo-4b and its star have always been rotating in sync since their formation about 1000 million years ago, or if the star’s rotation synchronized later. Studying such systems with COROT will help scientists gain valuable insight into star-planet interactions.

This is the first transiting exoplanet found with such a peculiar combination of mass and period of rotation. Astronomers believe there must be something unique about how it formed and evolved.

Original News Source: ESA

Mars’ Sticky Soil Strikes Again

Phoenix's scoop hovers over TEGA. Credit: NASA/JPL/Uof Arizona

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NASA’s Phoenix Mars Lander scraped up some icy soil with its robotic arm and scoop and then attempted to quickly deliver the sample to the oven on board. But not enough soil made it to the oven; the icy soil stuck to the scoop. Engineers determined the rasping and scraping activity collected a total of 3 cubic centimeters of icy soil, more than enough to fill the tiny oven cell of the Thermal and Evolved-Gas Analyzer, or TEGA. However, images returned from the lander Saturday showed that much of the soil remained lodged in the robotic arm’s scoop after the delivery attempt. “Very little of the icy sample made it into the oven,” said Barry Goldstein, Phoenix project manager. “We believe that the material that was intended for the targeted cell is the material that adhered to the back of the scoop.”


Once the sample had been collected, the robotic arm tilted its scoop and ran the rasp motor several times in an attempt to sprinkle the sample into the oven whose doors were wide open. The scoop was then inverted directly over the doors. A screened opening over the oven measures about 10 centimeters (4 inches) long by 3 centimeters (1.5 inches) wide. The oven itself is roughly the size of an ink cartridge in a ballpoint pen.

But TEGA’s sensors didn’t detect enough soil in the oven for the oven doors to close. Commands were also sent to vibrate the screen on TEGA several times. The good news there is that the vibrating did not cause the oven to short circuit, a problem that occurred earlier and engineers have been worried that vibrating could possibly short out the entire instrument. But TEGA lives on for the team to try again to quickly deliver the icy soil to the oven before the ice sublimates away in Mars thin atmosphere. The ice can exist just under Mars surface, protected by the soil.

Goldstein said the team will adjust their sample drop-off strategy and try again.

Original News Source: Phoenix News

Apollo Astronaut Mitchell Says Aliens Have Visited Earth

Apollo 14 Astronaut Edgar Mitchell. Credit: NASA

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This story has been spreading like wildfire across the internet, as well as other news sources, which is not surprising given the topic. In a radio interview in the UK, and in a subsequent article in the Daily Register, former Apollo astronaut Edgar Mitchell said he believes there is life on other planets. OK, that’s not much of a bombshell. But then he went on to say that aliens have visited Earth, and our governments have been covering it up. That was the shocker. Mitchell said he was “privileged enough to be in on the fact that we’ve been visited on this planet and the U.F.O. phenomena is real.” While he didn’t offer any real facts or say that he has actually seen aliens, he said big organizations will soon be offering full disclosure. NASA officials responded to Mitchell’s comments fairly politely with this comment: “NASA does not track UFOs. NASA is not involved in any sort of cover up about alien life on this planet or anywhere in the universe. Dr. Mitchell is a great American, but we do not share his opinions on this issue.”

Mitchell was a member of Apollo 14, and was the sixth man to walk on the moon. While he didn’t offer any real proof of his claims, he does seemingly have credentials. However, he alone among the Apollo astronauts makes these types of claims, and has been saying things like this for quite some time. He said on the way home from the moon he had a “transformational, transcendental experience.” After his flight he started the Institute of Noetic Sciences, which “conducts and sponsors leading-edge research into the potentials and powers of consciousness.”

There was another interesting statement by Mitchell during this interview: “There’s more nonsense out there about this than there is real knowledge.”

Of course, the UFO folks have glommed onto these latest statements by Mitchell, but here’s what some of the more reputable news sites have been saying:

New York Times Blog: “While Mr. Mitchell, 77, is certainly entitled to his own views on the issue, the rest of us may need to wait for something more convincing.”

Huffington Post: “Mitchell, a member of the Apollo 14 team, has long held these beliefs despite the fact that he himself has never seen neither an alien or a U.F.O.”

NASA Watch’s Keith Cowing: “I assume you have proof to back up your extraterrestrial conspiracy mongering, Ed.”

Robert Pearlman, the editor of CollectSpace, wrote the following on an online forum:

Based on the nine minute call, it (a) doesn’t seem to be anything tremendously different from prior comments and writings by Dr. Mitchell, and (b) he isn’t actually claiming first-hand knowledge but rather repeating what he was told by others. It is no secret that Dr. Mitchell’s Noetic Science Institute attracts those that believe in extraterrestrials and that he has attended numerous conferences where they have been on the agenda for discussion, thus what he says here is of little surprise (and some might argue, consequence).

Irene Klotz from Discovery interviewed Mitchell after his UK radio interview and here’s an excerpt:

Irene Klotz: I wanted to ask you if there was anything about the radio interview you did that was different from what you’ve said in the past.

Edgar Mitchell: No, there’s nothing different. Several of (the reports of the interview) that I’ve seen come around have some flaws in them. Some of the reports pushed it or spun it incorrectly. NASA had nothing to do with anything I’ve done. I wasn’t briefed by NASA. There haven’t been any sightings as a result of my flight service there, so if that part of it comes out on anything you’ve seen it is just totally wrong.

In this Discovery interview, and in previous interviews, Mitchell has not offered any definite proof of his claims, and said he’s only been “told by people who were utterly sworn to secrecy” about alien visits to Earth. Mitchell grew up in Roswell, New Mexico.

All in all, unless Mitchell can offer definitive proof, his claims will have to be put in the same class as anyone else that makes similar claims, despite his background. Even with the prevalence of cameras and video cameras among the general public and with an abundance of investigative news reporters out there (all wanting to break the news story of the millennium) still, no one has been able to produce credible proof of aliens visiting Earth.

As the Bad Astronomer Phil Plait has said repeatedly, the people constantly looking at the skies, professional and amateur astronomers, have made no claims of UFO’s or aliens visiting Earth. They know what they are looking at in the sky.

For a dose of reality, please see Phil’s take on UFO’s.

Phoenix in the Land of Mars’ Midnight Sun

Mars' Midnight Sun. Credit: NASA/JPL-Caltech/U of Arizona/Texas A&M University

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This panorama mosaic of images was taken by the Surface Stereo Imager on board NASA’s Phoenix Mars Lander. This mosaic documents the midnight sun during several days of the mission, from Sol 46, or the 46th day of the mission to Sol 56 (that would be to July 12 – 22, 2008 here on Earth.) The foreground and sky images were taken on Sol 54, when the lander pulled an all-nighter to coordinate work with the Mars Reconnaissance Orbiter. The solar images were taken between 10 p.m. and 2 a.m., local solar time, on the different nights of the 11 sol period. During this period, the sun’s path got slightly lower over the northern horizon, causing the lack of smoothness to the curve. This pan captures the polar nature of the Phoenix mission in its similarity to time lapse pictures taken above the Arctic Circle on Earth.

The latest activities of the lander has brought it closer to analyzing a sample of icy soil in the TEGA oven.

On Tuesday and Wednesday, Phoenix used its robotic arm to scrape the top of the hard layer in the trench called “Snow White.”

“We are monitoring changes between the scrapes,” said Doug Ming of NASA Johnson Space Center. “It appears that there is fairly rapid sublimation of some of the ice after scraping exposes fresh material, leaving a thin layer of soil particles that had been mixed with the ice. There’s a color change from darker to bluer to redder. We want to characterize that on Sol 58 to know what to expect when we scrape just before collecting the next sample.”

The science team is preparing to quickly collect a sample from the hard layer of Snow White and deliver it to one of the eight ovens of Phoenix’s Thermal and Evolved-Gas Analyzer (TEGA). Doors to the oven have been opened to receive the sample. TEGA will “bake and sniff” the samples to analyze the composition of the soil and ice.

On Wednesday the team also checked out the heater on TEGA is working properly, to verify that pressure sensors can be warmed enough to operate properly early in the Mars morning.

“For the next sample, we will be operating the instrument earlier in the morning than we have before,” said William Boynton of the University of Arizona, lead scientist for TEGA. “It will be almost the coldest part of the day, because we want to collect the sample cold and deliver it cold.”

On the day when Phoenix will deliver the next sample to TEGA, the team plans to have lander activities begin about three hours earlier than the usual start time of about 9 a.m. local solar time.

On Thursday, one set of imaging commands will check a northwestern portion of the horizon repeatedly during early afternoon to see whether any dust devils can be seen. This will be the first systematic check by Phoenix for dust devils. The Mars Rover Spirit was able to image sequences of dust devils in its location, south of Mars’ equator.

Original News Source: Phoenix News

What Are YOU Doing for the International Year of Astronomy?

In 1609, Galileo Galilei looked at the heavens through a telescope for the first time, and things on Earth haven’t been the same since. To celebrate the 400th anniversary of this advent of scientific discovery and thought, people and organizations from around the globe are coordinating a world-wide, year-long program called the International Year of Astronomy (IYA). Some of the goals of IYA are to stimulate worldwide interest in astronomy and science, especially among young people, to provide as many people as possible with an “astronomy experience,” and to support science education in both formal and informal settings. Currently, 118 countries are going to be part of IYA. The program has the support of the United Nations, the International Astronomical Union, the US’s National Science Foundation and all the space agencies around the world. Recently, the US House of Representatives passed a resolution supporting IYA. Right now IYA is in the planning and coordination stage. But for IYA to be a success, says Doug Isbell, one of the co-chairs for the US IYA program, it’s going to take a coordinated effort from volunteers around the world who want to share their love of space and astronomy. So, it’s time to start thinking about what YOU are going to do for IYA. And even though we’ve posted the IYA trailer on UT before, here it is again to help get you in the mood:



So, what’s in it for you? Plenty. There are a myriad of ways for everyone to get involved in IYA, whether its just attending a star party, or helping to coordinate a local event, or making a financial contribution.

One of the goals of IYA is to provide as many people as possible with the experience of looking through a telescope. Currently, IYA is designing a telescope kit, called the Galileoscope, to distribute to schools and science centers around the world. “We have a goal of approximately 1 million Galileoscopes world wide” said Isbell. “We want everyone to have a high quality, aha! experience. From networking and experience, we know that experience is something like being able to see Saturn’s rings. That drives you to a 40 or 45 power telescope, which is more ambitious than we originally thought.” The telescope kit will come with a educational curriculum, and is designed to be to be a science experience in either a classroom or an informal science center.

IYA would like to offer these scopes free to people around the world, and is looking for funding. “This is a big funding challenge,” said Isbell. “We’re getting close to the design, but we’re still looking for the chunk of money that will get us to the production phase.”

The overall US goal, said Isbell, is to offer an engaging astronomy experience to every person in the country in some fashion, whether it is in person or virtual, and to build partnerships for the future in educational outreach.

“Within the US, we have plans to foster star parties around the country, in coordination with local astronomy groups,” said Isbell. “There will be national and international efforts to observe particular objects, like Jupiter that will be in a good alignment in August of 2009. Also, we’re promoting the dark skies concept of preserving the night sky for observers, and we’re trying to foster a more formal research project to observe the variable binary star Epsilon Aurigae. It’s going through an eclipse that comes around every few decades, and this is a chance for the more dedicated observers and teacher/student researchers to study this star.”

One of the exciting events happening in conjunction with IYA is the production of a PBS special called “400 Years of the Telescope,” produced by Interstellar Studios, headed by Kris Koenig. Not only will there be a television special, but planetarium shows and interactive educational activities are being coordinated for as well for IYA. The 400 Years of the Telescope website has a newsletter available, which is also where you can find info on the US IYA effort. Subscribe to the newsletter here. UT will provide more information on “400 Years of the Telescope” as the air date gets closer.

Check out IYA’s website, which provides a centralized outlet for people to publicize and learn about events, activities and materials available online. Here’s the US IYA site. See how you can get involved. You can also find IYA on several of the social networking sites, like MySpace, and Facebook.

Universe Today will provide updated information about IYA, as well as details about the different facets of IYA in upcoming articles.

This Week’s “Where In The Universe” Challenge

It’s Wednesday, so that means its time for another “Where In The Universe” challenge to test your visual knowledge of the cosmos. Guess the location of this image, and give yourself extra points if you can name the spacecraft responsible for the photo. Remember, you have 8 planets, 169 known moons, a handful of dwarf planets (there’s a new one!) and lots of asteroids in our solar system to choose from. We’re also up to over 300 known exoplanets now; however we don’t have the capability to image them quite yet, so you can cross them off your potential answer list. Don’t cheat – make your guess before you look below!


On October 13, 2000, the Expedition 3 crew of the International Space Station, took this interesting photo of the Brahmaputra River in Tibet. This river carves a narrow west-east valley between the Tibetan Plateau to the north and the Himalaya Mountains to the south, as it rushes eastward for more than 1,500 km in southwestern China. The 15-km stretch shown here is about 35 km south of the ancient Tibetan capital of Lhasa. As you can see the river flow becomes intricately braided as it works and reworks its way through extensive deposits of erosional material. This pattern indicates a combination heavy sediment discharge from tributaries and reduction of the river’s flow from either a change in gradient or perhaps even climate conditions over the watershed. The area is also known for strong, persistent westerly winds which also shapes the region.

Photos such as this one bring immediate visual understanding and appreciation of natural processes in some of the most remote locations on Earth.

How did you do?

More info on this image.

New “Sunglasses” Help Astronomers See Light Near Black Holes

Looking at the sunset on Mauna Kea through IRPOL. Credit: U of Hawaii

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Although we can’t actually see a black hole, we can see the black hole’s effect on nearby matter. But even that is difficult because infrared light from clouds of dust and gas usually pollutes the view. But astronomers have found a way to get a clean view of the disks surrounding black holes by using a polarizing filter in the infrared. This technique works in particular when the region immediately surrounding the black hole emits a small amount of scattered light. Since scattered light is polarized, astronomers can use a filter that works like polarized sunglasses on large telescopes to detect this small amount of scattered light and measure it with unprecedented accuracy. Scientists have theorized these luminous disks existed around black holes, but until now have not been able to observe them.

The United Kingdom Infrared Telescope (UKIRT) on Mauna Kea in Hawaii has such an infrared filter, called a polarimeter (IRPOL). Astronmers have been using UKIRT and IRPOL and other telescopes for many years to search for proof that such a luminous supermassive black hole is accreting materials in a particular form of disk, where the disk shines directly using the gravitational binding energy of the black hole. Theorists have long thought that such disks should exist, and while there is a well-developed theory for it, until now theory and observations have been contradictory.

Dr. Makoto Kishimoto of the Max Planck Institute, principal investigator of this project, says: “After many years of controversy, we finally have very convincing evidence that the expected disk is truly there. However, this doesn’t answer all of our questions. While the theory has now been successfully tested in the outer region of the disk, we have to proceed to develop a better understanding of the regions of the disk closer to the black hole. But the outer disk region is important in itself – our method may provide answers to important questions for the outer boundary of the disk.”

A polarizing filter allows the colors of disk to be seen. Figure by M. Kishimoto, with cloud image by Schartmann
A polarizing filter allows the colors of disk to be seen. Figure by M. Kishimoto, with cloud image by Schartmann

Dr. Robert Antonucci of the University of California at Santa Barbara, a fellow investigator, says: “Our understanding of the physical processes in the disk is still rather poor, but now at least we are confident of the overall picture.”

Astronomers are hoping this new method will provide more information about the disks surrounding black holes in the near future.

Now, next on the agenda should be developing a suitable gravitational wave detector to confirm the existence of black holes!

Original News Source: University of Hawaii

Ancient Galactic Magnetic Fields Stronger than Expected

Spiral galaxy M 51 with magnetic field data. Credit: MPIfR Bonn

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The origin of magnetic fields in our universe is a mystery. But magnetic fields are a key part of the interstellar medium and scientists are finding they may play a major role in galactic formation, such as helping to form the spiral arms of galaxies. Until recently, however scientists believed the strength of galactic magnetic fields increased over time as galaxies matured, and in the early universe, these magnetic fields were initially very weak. But, recently a team of scientists looking back to probe the ancient universe as it existed 8 to 9 billion years ago has found that the magnetic fields of ancient galaxies were just as strong as they are today, prompting a rethinking of how our galaxy and others may have formed.

Using the European Southern Observatory’s 8-meter telescope located in Chile, a team of scientists from the Los Alamos National Laboratory and the Swiss Federal Institute of Technology studied 70 galaxies similar to the Milky Way at optical wavelengths. They combined their data with 25 years of radio wave observations of magnetic fields that measured how far the radio waves were pulled toward the red end of the spectrum, known as “redshift” using Faraday rotation measures.

Serving as a looking glass into the past, the powerful telescope at the European Southern Observatory, adding to the radio rotation measures, allowed the scientists to observe surprisingly high magnetic fields between 8 billion and 9 billion years ago in the 70 galaxies studied. That means that several billion years before the existence of our own sun, and within only a few billion years of the Big Bang, ancient galaxies were exerting the tug of these strong magnetic fields.

“It was thought that, looking back in the past, earlier galaxies would not have generated much magnetic field,” said Philipp Kronberg of LANL. “The results of this study show that the magnetic fields within Milky Way-like galaxies have been every bit as strong over the last two-thirds of the Universe’s age as they are now-and possibly even stronger then.”

Astronomers had thought a mechanism called a dynamo, which transfers mechanical energy into magnetic energy was responsible for galactic magnetic fields. In that case, with the right configuration gas flow could generate a higher magnetic field from a weaker seed field. (Again, we have yet to understand how galactic magnetic fields originally form.) But this new research suggests that the magnetic fields in galaxies did not arise due to a slow, large-scale dynamo effect, which would have taken 5 billion to 10 billion years to reach their current measured levels.

“There must be some other explanation for a much quicker and earlier amplification of galactic magnetic fields,” Kronberg said. “From the time when the first stars and galaxies formed, their magnetic fields have probably have been amplified by very fast dynamos. One good possibility is that it happened in the explosive outflows that were driven by supernovae, and possibly even black holes in the very earliest generations of galaxies.”

This realization brings a new focus on the broader question of how galaxies form. Instead of the commonly held view that magnetic fields have little relevance to the genesis of new galaxies, it now appears that they are indeed important players. If so, strong magnetic fields a long time ago are one of the essential ingredients that explain the very existence of our galaxy and others like it.

Original News Source: Los Alamos National Lab

Phoenix Lander Couldn’t Sleep At All Last Night

TEGA oven doors wide open. Credit: NASA/JPL-Caltech/University of Arizona/Texas A&M University

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For the first time, the Phoenix lander stayed up all night. But there was no partying for the little lander, just hard work. Phoenix coordinated its schedule to work together with the Mars Reconnaissance Orbiter to make joint observations to study Mars’ atmosphere. More on that in a minute, but the other big news from the Phoenix lander is that the doors to the Thermal and Evolved Gas Analyzer (TEGA) oven successfully opened, and the device is now ready to accept a sample of icy soil. If you remember, way back in the beginning of the mission, on about Sol 8, the first time the science team relayed orders for the spring-loaded oven doors to open, the doors only opened partially and the team had to vibrate the oven to get the soil inside. But this time, the 10 cm (4 inch) doors stands wide open, and today Phoenix will perfect its techniques to quickly get the icy soil sample inside the oven before the ice sublimates.

Now, about those atmospheric observations: Phoenix used its weather station, stereo camera and conductivity probe to monitor changes in the lower atmosphere and ground surface at the same time MRO studied the atmosphere and ground from above. The orbiter flew repeatedly over Phoenix’s location last evening, so it was good timing for a coordinated effort.

“We are looking for patterns of movement and phase change,” said Michael Hecht, lead scientist for Phoenix’s Microscopy, Electrochemistry and Conductivity Analyzer, which includes the lander’s fork-like thermal and conductivity probe. “The probe is working great. We see some changes in soil electrical properties, which may be related to water, but we’re still chewing on the data.”

The probe was inserted into the soil Sunday for more than 24 hours of measurements coordinated with the atmosphere observations. One goal is to watch for time-of-day changes such as whether some water alters from ice phase to vapor phase and enters the atmosphere from the soil.

The Phoenix team’s plans also include commanding the lander to conduct additional testing of the techniques for collecting a sample of icy soil. When the team is confident about the collecting method, it plans to use Phoenix’s robotic arm to deliver an icy sample to an oven of TEGA.

The team wants to make sure their techniques will quickly bring the soil into the oven, as it’s possible the oven will only work for one more test. The vibrating done to get the soil into the oven for the previous test caused a short circuit that may happen again the next time the oven is activated. The short could be fatal to the oven, but of course, we’re all still holding out hope for a better case scenario.

Original News Source: Phoenix News site