Universe Today

June 9, 2010December 24, 2015 by Ryan Anderson

Ice Caves Possible on Mars

The circular black features in this 2007 figure are caves formed by the collapse of lava tubes on Mars. Image credit: NASA/JPL-Caltech/ASU/USGS

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New results published in the journal Icarus suggest that caves on Mars may provide future astronauts with more than just shelter. In many locations, even far from the poles, the caves may actually trap water ice.

Ice caves are made of rock, but they contain ice year-round. (Not to be confused with glacier caves, which are caves made of ice!) Ice caves can be found on the Earth even where surface temperatures are above freezing for months at a time. This happens because cold winter air sinks into the cave and is trapped, but during the summer, the circulation in the cave shuts off: it is full of dense cold air so the warm air outside can’t get in.

Now, in a study led by Kaj Williams of NASA Ames, scientists have used simulations of the global climate and assumptions about the thermal properties of the surface to figure out where on Mars similar cold-trapping might occur. Their results show that a significant portion of the martian surface has the right conditions for ice to accumulate in caves.

Even more tantalizing, the huge volcanic provinces of Tharsis and Elysium look to be particularly good at accumulating ice. This is important because caves formed by collapsing lava tubes have been seen on the flanks of these volcanoes. Lava tube caves on Earth tend to have limited air circulation, making them good candidates for ice accumulation.

Astronauts on the surface of Mars will likely need to take cover underground to avoid the harsh radiation environment of the surface. Natural caves such as lava tubes have been suggested as ideal ready-made shelters for astronauts, and they are only looking better. Not only could ice caves provide water as a resource, the ice could preserve valuable records of past climate cycles, and the caves may be important habitats for past or present martian life.

Williams and his team plan to continue refining their models, particularly focusing on the Tharsis and Elysium regions, using higher-resolution atmospheric models and more precise geologic data to pinpoint areas that are best for cave-ice formation.

Ice formations in a terrestrial ice cave in Montenegro. © copyright by Jack Brauer.

June 9, 2010December 24, 2015 by Nancy Atkinson

Delays Likely for Final Two Shuttle Missions

Endeavour on the launchpad in February 2010. Image: Nancy Atkinson

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The final scheduled space shuttle flight of Endeavour that has been targeted for late November 2010 is now likely to move to January or even February of 2011 because the primary payload, the $1.5 billion Alpha Magnetic Spectrometer, won’t be delivered to KSC in time to support the earlier date. Additionally, the penultimate scheduled mission, STS-133 Discovery, currently slated for September 16, could be delayed until October. As we reported yesterday, the first hint of Endeavour’s delay came from the announcement of a new opportunity for students to send experiments to space on Endeavour, and now Florida Today reports Kennedy Space Center Director Bob Cabana said it could even be February until the AMS is ready to go.

The White House and Congress are considering adding a third and final shuttle mission that could be flown next June. Each additional month of shuttle operations costs $100 million to $200 million. While the funding for shuttle missions technically only goes until the end of 2010, mission managers have said there is currently enough money in the shuttle budget for about two months of operations in 2011.

After that and possibly one more mission next summer, if funding is approved, Cabana, speaking at a National Space Club Florida Committee meeting, hopes to see KSC transition be able to support commercial space ventures and be less reliant on a single NASA program like Apollo, the shuttle or even Constellation.

“What we don’t want to be in the future is tied to any one large program,” Cabana said.

The delay for the AMS involves switching out to magnets that will last longer in space, since operations of the ISS have been extended to 2020. Liquid helium would have been used cool the superconducting magnet’s temperature to near absolute zero. But tests showed the helium would dissipate withing 2-3 years, leaving the seven-ton experiment useless.

Source: Florida Today

June 8, 2010December 24, 2015 by Nancy Atkinson

Exoplanet Hunting Robotic Telescope Sees First Light

TRAPPIST First Light Image of the Tarantula Nebula. Credit: ESO

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Great shot of the Tarantula nebula!

A new robotic telescope dedicated primarily to hunting for extra solar planets has opened its eyes. Although its first light image is of a nebula, the TRAPPIST (TRAnsiting Planets and PlanetesImals Small Telescope) at ESO’s La Silla Observatory in Chile will focus on detecting and characterizing planets located outside of our solar system. The new telescope will also study comets.

“The two themes of the TRAPPIST project are important parts of an emerging interdisciplinary field of research — astrobiology — that aims at studying the origin and distribution of life in the Universe,” said Michaël Gillon, who is in charge of the exoplanet studies.

“Terrestrial planets similar to our Earth are obvious targets for the search for life outside the Solar System, while comets are suspected to have played an important role in the appearance and development of life on our planet,” adds his colleague Emmanuël Jehin, who leads the cometary part of the project.

TRAPPIST will make high precision measurements of “brightness dips” that might possibly be caused by exoplanet transits. During such a transit, the observed brightness of the star decreases slightly because the planet blocks a part of the starlight. The larger the planet, the more of the light is blocked and the more the brightness of the star will decrease.

For studying comets, TRAPPIST is equipped with special large, high quality cometary filters, allowing astronomers to study regularly and in detail the ejection of several types of molecules by comets during their journey around the Sun.

“With dozens of comets observed each year, this will provide us with a unique dataset, bringing important information about their nature,” says Jehin.

TRAPPIST is a lightweight 0.6-metre robotic telescope, fully automated and moving precisely across the sky at a high speed. The observing program is prepared in advance and the telescope can perform a full night of observations unattended. A meteorological station monitors the weather continuously and decides to close the dome if necessary. The control center for this telescope is in Liège, Belgium, about 12,000 km away.

See more first light images from TRAPPIST, including Omega Centauri and M83 at the ESO website.

June 8, 2010December 24, 2015 by Nancy Atkinson

The Earth and Moon May Have Formed Later Than Previously Thought

The collision between "Proto-Earth" and Theia, from which the Earth and Moon were created 4,500-4,400 million years ago. Both planets had a massive iron core when they collided and created the Moon and Earth.

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The Earth and Moon were created as the result of a giant collision between two planets the size of Mars and Venus. Until now it was thought to have happened when the solar system was 30 million years old or approximately 4.5 billion years ago. But new research shows that the Earth and Moon may have formed much later – perhaps up to 150 million years after the formation of the solar system.

“We have determined the ages of the Earth and the Moon using tungsten isotopes, which can reveal whether the iron cores and their stone surfaces have been mixed together during the collision,” said Tais W. Dahl, from the Niels Bohr Institute at the University of Copenhagen in collaboration with professor David J. Stevenson from the California Institute of Technology (Caltech).

The planets in the solar system were created by collisions between planetary embryos orbiting the newborn sun. In the collisions the small planets congealed together and formed larger and larger planets. When the gigantic collision occurred that ultimately formed the Earth and Moon, it happened at a time when both planetary bodies had a core of metal (iron) and a surrounding mantle of silicates (rock). But when did it happen and how did it happen? The collision took place in less than 24 hours and the temperature of the Earth was so high (7000º C), that both rock and metal must have melted in the turbulent collision. But were the stone mass and iron mass also mixed together?

The age of the Earth and Moon can be dated by examining the presence of certain elements in the Earth’s mantle. Hafnium-182 is a radioactive substance, which decays and is converted into the isotope tungsten-182. The two elements have markedly different chemical properties and while the tungsten isotopes prefer to bond with metal, hafnium prefers to bond to silicates, i.e. rock.

It takes 50-60 million years for all hafnium to decay and be converted into tungsten, and during the Moon forming collision nearly all the metal sank into the Earth’s core. But did all the tungsten go into the core?

“We have studied to what degree metal and rock mix together during the planet forming collisions. Using dynamic model calculations of the turbulent mixing of the liquid rock and iron masses we have found that tungsten isotopes from the Earth’s early formation remain in the rocky mantle,” said Tahl.

The new studies imply that the moon forming collision occurred after all of the hafnium had decayed completely into tungsten.

“Our results show that metal core and rock are unable to emulsify in these collisions between planets that are greater than 10 kilometers in diameter and therefore that most of the Earth’s iron core (80-99 %) did not remove tungsten from the rocky material in the mantle during formation” said Dahl.

The result of the research means that collision that created the Earth and the Moon may have occurred as much as 150 million years after the formation of the solar system, much later than the 30 million years that was previously thought.

The research results have been published in the scientific journal, Earth and Planetary Science Letters.

From a University of Copenhagen press release.

June 8, 2010January 22, 2016 by Nancy Atkinson

NASA Releases First Ever Video of Inside of Space Shuttle After Landing

NASA has released the first-ever up close video available for the public, taken from inside a space shuttle after landing, showing the checkout procedures and the “towback” to the Orbiter Processing Facility. It was taken on May 26, 2010 following shuttle Atlantis’ landing following the STS-132 mission.
Continue reading “NASA Releases First Ever Video of Inside of Space Shuttle After Landing”

June 8, 2010December 24, 2015 by Nancy Atkinson

Attention Teachers and Students: Fly An Experiment on Final Shuttle Mission

An astronaut works on an experiment outside the ISS. Credit: NASA

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We just received an exciting note from Dr. Jeff Goldstein, the Director for the National Center for Earth and Space Science Education. There is a unique and historic opportunity for students in grades 5-12 to fly an experiment on the final scheduled space shuttle mission, STS-134, through the Student Spaceflight Experiments Program (SSEP).

There is room for 45 different experiments to be flown for 10 days aboard Shuttle Endeavour, each designed by middle school and high school classes across the U.S., and with astronauts operating the experiments. Launch is tentatively scheduled for November 2010, but a launch slip to mid-January is expected, enabling this extra student spaceflight experiments opportunity.

But it’s time-critical! All the details of the experiments have to be submitted by the first part of August, 2010, and each team does have to secure their own funding.

So check out the SSEP website for details, and spread the word to all the teachers, students and school administrators you know!

This program does hinge on whether the flight will be delayed until January. The issue is the big new spectrometer that is going to the International Space Station, which will use a different type of magnet than originally planned. The Alpha Magnetic Spectrometer was supposed to fly in July, then was switched to the final scheduled shuttle flight and tentatively delayed to November to allow for the change in magnets. But now it appears it might slip to January, 2011.

But the delay is also providing this potential new opportunity. So, teachers, students — take advantage! And good luck!

June 7, 2010April 26, 2016 by Nancy Atkinson

Man-Made Aurora Will Help to Better Predict Space Weather

Northern Lights — The Aurora Borealis seen in Alaska.

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New experiments that create a man-made aurora are helping researchers better understand how nitrogen in our atmosphere reacts when it is bombarded by the solar wind. Scientists from the Jet Propulsion Laboratory fired electrons of differing energies through a cloud of nitrogen gas to measure the ultraviolet light emitted by this collision, and the findings show our previous understanding of the processes that create the aurorae – which can also adversely affect orbiting satellites– may have been in error.

For more than 25 years, our understanding of terrestrial space weather has been partly based on incorrect assumptions about how nitrogen — the most abundant gas in our atmosphere –reacts when it collides with electrons produced by energetic ultraviolet sunlight and solar wind.

The new research has found that well-trusted measurements published in a 1985 journal paper by researchers Ajello and Shemansky contain a significant experimental error, putting decades of space weather findings dependent on this work on unstable ground.

New technology has allowed the researchers to better create and control the collisions and avoid the analytical pitfalls that plagued the 1985 findings.

The new results from the team at JPL suggest that the intensity of a broad band of ultraviolet light emitted from the collision changes significantly less with bombarding electron energies than previously thought.

The researchers studied ultraviolet light within the so called ‘Lyman-Birge-Hopfield’ (LBH) band to better understand the physical and chemical processes occurring in our upper atmosphere and in near-Earth space.

“Our measurement of LBH energy-dependence differs significantly from widely accepted results published 25 years ago,” said Dr. Charles Patrick Malone from JPL. “Aeronomers can now turn the experiment around and apply it to atmospheric studies and determine what kind of collisions produce the observed light.”

In addition to helping researchers to better understand space weather, which can help protecting the ever-growing population of satellites in Earth orbit, the new findings will also help further our understanding of phenomena like Aurora Borealis (the Northern Lights) and similarly the Aurora Australis (Southern Lights), which are caused by collisional processes involving solar wind particles exciting terrestrial oxygen and nitrogen particles at the North and South Pole.

The researchers are hopeful that their findings will also assist the Cassini project understand happenings on Saturn’s largest moon, Titan, as LBH emissions have been detected by the orbiting robotic spacecraft.

The research was published in IOP Publishing’s Journal of Physics B: Atomic, Molecular and Optical Physics.

June 7, 2010December 24, 2015 by Nancy Atkinson

New Mars Maps Show Evidence of Ancient Lakes

Hellas Planitia extends across about 50° in longitude and more than 20° in latitude. From data from the Mars Orbiter LaserAltimeter (MOLA).

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Was the expansive Hellas Basin on Mars at one time a giant lake? A new geologic mapping project shows evidence of sedimentary deposits consistent with what would relate to large standing bodies of water. Fine-layered outcrops around the eastern rim of Hellas basin have been interpreted as a series of sedimentary deposits resulting from erosion and transport of highland rim materials into a basin-wide standing body of water. “This mapping makes geologic interpretations consistent with previous studies, and constrains the timing of these putative lakes to the early-middle Noachian period on Mars, between 4.5 and 3.5 billion years ago,” said Dr. Leslie Bleamaster, research scientist at the Planetary Science Institute.

Hellas basin, more than 2,000 km across and 8 km deep, is the largest recognized impact structure on the Martian surface.

Using data from a variety of spacecraft, including the Viking Orbiter, the Mars Global Surveyor and Mars Odyssey, the researchers characterized the geologic materials and processes that have shaped the Hellas Planetia region on the southern hemisphere of Mars.

The mapping team searched through high-resolution images and found the eastern part of Hellas Planitia, where the fine-layered floor deposits were discovered, “is unique in nature representing a confluence between sedimentary sources and sinks.”

“Our mapping and evaluation of landforms and materials of the Hellas region from the basin rim to floor provides further insight into Martian climate regimes and into the abundance, distribution, and flux of volatiles through history,” Bleamaster said.

The mapping project reinforces earlier research that initially proposed Hellas-wide lakes citing different evidence in the west, he said. Take a look a the new map along with a explanatory pamphlet.

Source: Planetary Science Institute

June 7, 2010December 24, 2015 by Fraser Cain

Pictures of Australia

Kata Tjuta (The Olgas), Northern Territory, Australia

Here are some pictures of Australia, taken from space. You can make any of these images into your computer wallpaper. Just click on an image to make it larger, then right-click and choose “Set as Desktop Background”.

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This is a photograph of Uluru-Kata Tjuta National Park, an isolated region in Australia’s Northern Territory. It’s famous for these isolated mountains known as inselbergs.

Australia’s Great Barrier Reef

Here’s an image of the Great Barrier Reef from space. This reef extends for 2,000 km along the coast line of Australia.

This is an image of Spider Crater, in Western Australia. Geologists believe it was formed between 900 and 600 million years ago, when a large asteroid struck the Earth.

Here’s a photo of Perth, one of the largest cities in Australia. It’s the capital of Western Australia, and home to about 1.5 million people.

Here’s an image of Sandy Cape, on Fraser Island; the largest sand island in the world.

We’ve written many articles about Australia for Universe Today. Here’s an article about a huge river of dust above Australia, and here’s an article about Australian bushfires seen from space.

If you’d like more pictures of Australia, check out Visible Earth Homepage. And here’s a link to NASA’s Earth Observatory.

We’ve also recorded an episode of Astronomy Cast all about planet Earth. Listen here, Episode 51: Earth.

June 7, 2010December 24, 2015 by Nancy Atkinson

Send Your Face to Space On Final Two Shuttle Missions

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If NASA offered you a ride on one of the final two scheduled space shuttle missions, you’d go, right? I know I would, so that’s why I immediately signed up for NASA’s newest public participation campaign, “Send Your Face to Space.” If I can’t go, at least my face is heading up to LEO.

Here’s how to participate and become part of history:

Head to the “Send Your Face to Space” website.

Hit the “Participate” button and upload your image, which will be flown aboard the space shuttle. Don’t have a picture to upload? No problem, just skip the image upload and NASA will fly your name only on your selected mission.

Next… Print and save the confirmation with your flight information.

Later… Return to the site after the landing to print your Flight Certificate – a commemorative certificate signed by the Mission Commander.

The website also provides a participation map showing where participants are from and, relative to each other, how many are taking part from each country.