Posted on by Nancy Atkinson

More Mars Avalanches from HiRISE, Oh My!

A shot monitoring the original site of active frost-dust avalanches (ESP_016173_2640) Credit: NASA/JPL/University of Arizona

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In 2008, the HiRISE camera on the Mars Reconnaissance Orbiter was monitoring a certain region on Mars for changes in frost patterns as spring progressed, and serendipitously captured an avalanche in action. This year, the HiRISE team has been on the lookout, ready to capture more avalanches as spring approaches in Mars’ northern hemisphere. They’ve been successful — and how! This awesome shot was captured on January 27, 2010 of a steep cliff in the northern polar region of Mars, and shows at least three isolated clouds of particles falling from the cliff. The HiRISE teams says that these clouds, rolling or hovering close to the ground likely reach up tens of meters high (up to 180 feet)! The avalanches are a result of carbon-dioxide frost that clings to the scarp in the darkness of winter, and when sunlight hits them in the spring they loosen up and fall. The cliff, approximately 700 meters (2000 feet) high is made up of layers of water ice with varying dust content, roughly similar to the polar ice caps on Earth. But wait, there’s more! Yes, it’s avalanche season on Mars!

Another avalanche seen earlier in 2010. Credit: NASA/JPL/University of Arizona

Here’s another avalanche captured on January 12, 2010, and below, the HiRISE camera was trained on the same site that the original avalanche was captured back in 2008.

A shot monitoring the original site of active frost-dust avalanches (ESP_016173_2640) Credit: NASA/JPL/University of Arizona

The HiRISE teams says that by looking at all of the individual instances of avalanches from all of the images will also allow them to piece together a sequence of snaphots of the whole avalanche process, from beginning (a stream of material falling down the cliff face) to end (lingering puffy clouds). Patrick Russell writes:

Based on this year’s observations, these events happen mostly in the middle of spring, roughly equivalent to April to early May on Earth. And, they are indeed more widespread than just this one scarp. All together, it seems this is a regular spring process at Mars’ north pole that may be expected every year – avalanche season! This information, in conjunction with the results of numerical modeling of the behavior of the materials involved, will help us find out what is causing these dramatic events.

For more wonderful images, check out the HiRISE website.

Posted on by Nancy Atkinson

Carnival of Space #148

This week’s Carnival of Space is hosted by Katie St.Laurent over at Celestial Spider.

Click here to read the Carnival of Space #148.

And if you’re interested in looking back, here’s an archive to all the past Carnivals of Space. If you’ve got a space-related blog, you should really join the carnival. Just email an entry to [email protected], and the next host will link to it. It will help get awareness out there about your writing, help you meet others in the space community – and community is what blogging is all about. And if you really want to help out, let Fraser know if you can be a host, and he’ll schedule you into the calendar.

Finally, if you run a space-related blog, please post a link to the Carnival of Space. Help us get the word out.

Posted on by Nancy Atkinson

Where In The Universe #99

It’s time once again for another Where In The Universe Challenge. Test your visual knowledge of the cosmos by naming where in the Universe this image was taken and give yourself extra points if you can name the spacecraft responsible for this picture. Post your guesses in the comments section, and check back on later at this same post to find the answer. To make this challenge fun for everyone, please don’t include links or extensive explanations with your answer. Good luck!

Also, I’d like to do something special for next week’s WITU Challenge. It will be number 100!! Send your ideas of dastardly intriguing stumpers to me at this email address.

UPDATE: The answer is now posted below.


Just what the heck is this thing? Answers ranged from Skeletor’s skull, to the back end of a space shuttle to the face on Mars to (my favorite) Wilson! (Tom Hanks’ pal in the movie Cast Away).

This is a gravitationally lensed quasar, PG 1115+080, that is split and distorted by the lensing. It was captured in infrared by the Hubble Space Telescope way back in 1998, and is one of the rare cases where a quasar is almost perfectly lined up with an intervening galaxy.

For more info on this image check out this HubbleSite page.

And check back next week for the big #100 of the WITU challenge!

Posted on by Nancy Atkinson

Is Our Universe Inside Another Larger Universe?

Wormhole. Credit: Internet Encyclopedia of Science

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A wormhole is a hypothetical “tunnel” connecting two different points in spacetime, and in theory, at each end of the wormhole there could be two universes. Theoretical physicist Nikodem Poplawski from Indiana University has taken things a step further by proposing that perhaps our universe could be located within the interior of a wormhole which itself is part of a black hole that lies within a much larger universe.

Whoa. I may have just lost my bearings.

As crazy as the concept of wormholes sounds, it does offer solutions to the equations of Einstein’s general theory of relativity. In fact, wormholes – also called an Einstein-Rosen Bridge — offer such a great solution that some theorists think that real wormholes may eventually be found or even created, and perhaps they could even be used for high-speed travel between two areas in space, or maybe even time travel.

However, a known property of wormholes is that they are highly unstable and would probably collapse instantly if even the tiniest amount of matter, such as a single photon, tried to travel though them.

But would it work – and could matter exist — if we were inside a wormhole inside a black hole inside another universe? Poplawski thinks so. He takes advantage of the Euclidean-based coordinate system called isotropic coordinates to describe the gravitational field of a black hole and to model the radial geodesic motion of a massive particle into a black hole.

“This condition would be satisfied if our universe were the interior of a black hole existing in a bigger universe,” Poplawski said. “Because Einstein’s general theory of relativity does not choose a time orientation, if a black hole can form from the gravitational collapse of matter through an event horizon in the future then the reverse process is also possible. Such a process would describe an exploding white hole: matter emerging from an event horizon in the past, like the expanding universe.”

So, a white hole would be connected to a black hole a wormhole, and is hypothetically the time reversal of a black hole. (Oh my, I’m now dizzy…)

Poplawski’s paper suggests that all astrophysical black holes, not just Schwarzschild and Einstein-Rosen black holes, may have Einstein-Rosen bridges, each with a new universe inside that formed simultaneously with the black hole.

“From that it follows that our universe could have itself formed from inside a black hole existing inside another universe,” he said.

IU theoretical physicist Nikodem Poplawski. Credit: Indiana University

By continuing to study the gravitational collapse of a sphere of dust in isotropic coordinates, and by applying the current research to other types of black holes, views where the universe is born from the interior of an Einstein-Rosen black hole could avoid problems seen by scientists with the Big Bang theory and the black hole information loss problem which claims all information about matter is lost as it goes over the event horizon (in turn defying the laws of quantum physics).

Poplawski theorizes that this model in isotropic coordinates of the universe as a black hole could explain the origin of cosmic inflation.

Could this be tested? Well, there is the issue that to see if an object could travel through a wormhole, the observer would have to be inside the wormhole as well, since the interior cannot be observed unless an observer enters or resides within.

A possible solution is that exotic matter wouldn’t collapse the wormhole, so we’d have to create – and be made of – exotic matter to keep the it open. But perhaps, as Poplawski proposes, if the wormhole is inside a black hole inside another universe it would work.

Anyone ready to give it a try?

“Radial motion into an Einstein-Rosen bridge,” Physics Letters B, by Nikodem J. Poplawski. (Volume 687, Issues 2-3, 12 April 2010, Pages 110-113.

Sources: Indiana University
, Internet Encyclopedia of Science

Posted on by Nancy Atkinson

Astronomers Image Mysterious Dark Object That Eclipses Epsilon Aurigae

Screenshot of the eclipse movie.

Epsilon Aurigae has baffled astronomers since the 1800’s, but new images are providing insight into this very unusual eclipsing binary star. While eclipsing binary stars aren’t unique in themselves, the way this star fades and then regains its brightness is inimitable and has not been fully understood, even after over 175 years of study. One theory has been that a large opaque disk seen nearly edge-on eclipses the primary star. The new images from an instrument developed at the University of Michigan appear to confirm that theory. “It kind of blows my mind that we could capture this,” said John Monnier from U-M. “There’s no other system like this known. On top of that, it seems to be in a rare phase of stellar life. And it happens to be so close to us. It’s extremely fortuitous.”

Epsilon Aurigae has a two-year-long eclipse that occurs every 27 years. The current eclipse started in August 2009 and amateur and professional astronomers have taken this opportunity to train as many telescopes on the event as possible.

Monnier led the development of the Michigan Infra-Red Combiner (MIRC) instrument, which uses interferometry to combine the light entering four telescopes at the CHARA array at Georgia State University and amplify it so that it seems to be coming through a device 100 times larger than the Hubble Space Telescope. MIRC allowed astronomers to “see” the eclipsing object for the first time.

The object that eclipses the primary star is dark — almost invisible — and is only seen as it passes in front of Epsilon Aurigae, the fifth brightest star in the northern constellation Auriga. Because astronomers hadn’t observed much light from it, one theory is the object was a stellar mass black hole. But the prevailing theory labeled it a smaller star orbited edge-on by a thick disk of dust. The theory held that the disk’s orbit must be in precisely the same plane as the dark object’s orbit around the brighter star, and all of this had to be occurring in the same plane as Earth’s vantage point. As unlikely as this alignment would be, it explained the observations.

The new images show that this is indeed the case. A geometrically thin, dark, dense, but partially translucent cloud can be seen passing in front of Epsilon Aurigae.

“This really shows that the basic paradigm was right, despite the slim probability,” Monnier said, and the disk appears much flatter than recent modeling from the Spitzer Space Telescope suggests. “It’s really flat as a pancake,” he said.
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While the “movie” of the disk passing in front of the star looks eerily like Saturn’s rings, Monnier doesn’t think the object is like a ring system.

“Ring systems are generally (always) quite sparsely populated and not optically thick,” Monnier said in an email to Universe Today. “Also ring systems have virtually no gas and settle into *extremely* thin layers. Both of these facts make it highly unlikley that the dust Eps Aur is in a “ring” because it wouldn’t be able to completely absorb so much of the star light during eclipse. That said, we don’t know much about the distribution — there might be a bit of a central hole as indicated by brightening of the star during mid-eclipse seen in the past.”

As to why this object is so dark, Monnier said, “At this epoch we are seeing the back side that can’t do any reflecting. We would expect some light to scatter off at other times in the orbit and would be worth looking for but requires very high angular resolution and high dynamic range. Note that the disk is not completely dark — the infrared glow of the cool dust grains have been seen in the 1980s and most recently in a Spitzer space telescope paper by Hoard et al.” (See the paper, “Taming the Invisible Monster: System Parameter Constraints for Epsilon Aurigae from the Far-Ultraviolet to the Mid-Infrared.”

MIRC has also allowed astronomers to see the shape and surface characteristics of stars for the first time. Previously, stars were mere points of light even with the largest telescopes.

“Interferometry has made high resolution imaging of distant objects a reality,” said Fabien Baron, a post-doctoral researcher at U-M who helped with the imaging in this study. “It most probably will solve many mysteries but also raise many new questions.”

The new findings will be published in the April 8 edition of Nature. Researchers from the University of Denver and Georgia State University also contributed to the research.

Sources: EurekAlert, email exchange with John Monnier

Posted on by Nancy Atkinson

Awesome Image of ISS Transiting Moon

ISS transit of the Moon. Image Credit: Photo courtesy of Fernando Echeverria

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The NASA Image of the Day is a webpage that everyone should visit everyday, as there are always great images of our explorations of space and Earth. But this one has a wow factor that is off the charts. It was taken just minutes before space shuttle Discovery launched this past Monday on April 5, 2010, as the International Space Station flew across the face of the moon over Kennedy Space Center in Florida. I know people who were there who thought it was an poignant event, but here photographer Fernando Echeverria captures the event at just the right milimoment as the ISS reached the dark area on the Moon. Amazing, and such incredible detail, too! Click the image or this link to go to the NASA Image of the Day site where you can find larger versions — suitable for framing or desktops!

Posted on by Nancy Atkinson

40 Years of Summer on Triton

Artist’s impression of how Triton, Neptune’s largest moon, might look from high above its surface. Credit: ESO/L. Calçada

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If you’re planning a trip to Neptune’s moon Triton, you’ll want to head to the southern hemisphere where it’s now just past mid-summer. Yes, distant Triton actually does have seasons, astronomers at ESO’s Very Large Telescope recently determined. “We have found real evidence that the Sun still makes its presence felt on Triton, even from so far away,” said astronomer Emmanuel Lellouch in an ESO press release. “This icy moon actually has seasons just as we do on Earth, but they change far more slowly.” According to the first ever infrared analysis of Triton’s atmosphere, the seasons last about 40 Earth years. But while summer is in full swing in Triton’s southern hemisphere, there’s no need to pack your bikini. The average surface temperature is about minus 235 degrees Celsius.

Oh, and you’ll also want to bring along a little breathable air. The ESO team also – unexpectedly – discovered carbon monoxide in Triton’s thin atmosphere, mixed in with methane and nitrogen.

The astronomer’s observations revealed that Triton’s thin atmosphere varies seasonally, thickening when warmed. When the distant sun’s rays hits Triton at their best summer angle, a thin layer of frozen nitrogen, methane, and carbon monoxide on Triton’s surface sublimates into gas, thickening the icy atmosphere as the season progresses during Neptune’s 165-year orbit around the Sun. Triton passed the southern summer solstice in 2000.

Voyager 2's view of Triton. Credit: NASA

So, while this action increases the thickness of the atmosphere, thus increasing the atmospheric pressure, you’ll still need a pressure suit as well for your visit. Based on the amount of gas measured, Lellouch and his colleagues estimate that Triton’s atmospheric pressure may have risen by a factor of four compared to the measurements made by Voyager 2 in 1989, when it was still spring on the giant moon. The Voyager data indicated the atmosphere of nitrogen and methane had a pressure of 14 microbars, 70,000 times less dense than the atmosphere on Earth. The data from ESO shows the atmospheric pressure is now between 40 and 65 microbars — 20,000 times less than on Earth.

Carbon monoxide was known to be present as ice on the surface, but Lellouch and his team discovered that Triton’s upper surface layer is enriched with carbon monoxide ice by about a factor of ten compared to the deeper layers, and that it is this upper “film” that feeds the atmosphere. While the majority of Triton’s atmosphere is nitrogen (much like on Earth), the methane in the atmosphere, first detected by Voyager 2, and only now confirmed in this study from Earth, plays an important role as well.

“Climate and atmospheric models of Triton have to be revisited now, now that we have found carbon monoxide and re-measured the methane,” said co-author Catherine de Bergh. The team’s results are published in Astronomy & Astrophysics

If we could actually visit Triton, it would likely be a very interesting destination as we know it has geologic activity and a changing surface – plus its unique retrograde motion would offer a unique view of the solar system.

While Triton is the seventh largest moon in our solar system, its distance and position from Earth makes it difficult to observe, and ground-based observations since Voyager 2 have been limited. Observations of stellar occultations (a phenomenon that occurs when a Solar System body passes in front of a star and blocks its light) indicated that Triton’s surface pressure was increasing in the 1990’s. But a new instrument on the VLT, the Cryogenic High-Resolution Infrared Echelle Spectrograph (CRIRES) has provided the chance to perform a more detailed study of Triton’s atmosphere. “We needed the sensitivity and capability of CRIRES to take very detailed spectra to look at the very tenuous atmosphere,” said co-author Ulli Käufl.

These observations are just the beginning for the CRIRES instrument, which will be extremely helpful in studying other distant bodies in our solar system, such as Pluto and other Kuiper Belt Objects. Pluto is often considered a cousin of Triton with similar conditions, and in the light of the carbon monoxide discovery on Triton, astronomers are racing to find this chemical on the even more distant Pluto.

Read the team’s paper.

Source: ESO

Posted on by Ken Kremer

Spectacular Radar Failed Belly Flip (Video) and Docking links Discovery to ISS

Space shuttle Discovery comes out of its 8 minute long back flip maneuver underneath the International Space Station as ISS astronauts collect high resolution photos of the heat shield for analysis to confirm it is intact and safe to land. Credit: NASA TV

Space Shuttle Discovery performed a spectacular “Radar Failed” rendezvous and docking at the International Space Station this morning (April 7) at 3:44 AM as the two massive ships were flying in formation some 225 miles over the Caribbean Sea near Caracas, Venezuela. Discovery’s blast off on April 5 began a two day pursuit of the station.

Hatches between Discovery and the ISS were opened at 5:11 AM EDT this morning, bringing together the seven-person shuttle crew and the six-person space station crew, to begin nine days of joint work and operations. The primary goal of the STS 131 mission is to outfit the station with numerous new science experiments, install a new crew sleeping quarter and to resupply stocks of essential parts and provisions.

[/caption]Discovery’s cargo bay is packed with the 27,000 pound Leonardo Multi Purpose Logistics module built by the Italian Space Agency and a nearly 4,000 pound ammonia cooling tank.

The joint crew of 13 people marks several notable historic firsts in space exploration, including the largest ever gathering of female astronauts and Japanese astronauts in space.

For the first time in history there are four female astronauts simultaneously working together in space. Discovery Mission Specialists Dottie Metcalf-Lindenburger, Stephanie Wilson and Japan Aerospace Exploration Agency (JAXA) astronaut Naoko Yamazaki join ISS Expedition 23 Flight Engineer Tracy Caldwell Dyson who rocketed to orbit just days ago on April 3 and arrived at the ISS on Easter Sunday.

This NASA image was taken by the centerline camera inside Discovery’s docking port as she initiates final approach to the International Space Station shortly before docking at 3:44 AM on April 7, 2010 during the STS-131 mission. Credit: NASA TV

Expedition 23 Flight Engineer Soichi Noguchi and Mission Specialist Yamazaki are the first JAXA Astronauts to fly in space at the same time. A horde of Japanese media and officials were on hand at KSC to witness the launch of Discovery. This space first is a source of great pride in Japan.

The flawless maneuvers linking the two giant ships together were conducted with “no radar” because of the failure of the high speed Ku-Band communications antenna normally used shortly after blast off on April 5.

The STS 131 astronaut crew led by Shuttle Commander Alan Poindexter had to rely on back up navigation systems to precisely track the station and guide Discovery to a position in front of the ISS and then gently dock at the Harmony module (Node 2). The crew are trained to rendezvous and dock without radar.

Station Commander Oleg Kotev and NASA astronaut TJ Creamer took high resolution images of Discovery’s heat shield during the 8 minute back flip maneuver to document the condition and integrity of the many thousands of critical thermal protection tiles fastened to the belly, wing leading edges and nose cap of Discovery.

The pair snapped hundreds of photos using 400 mm and 800 mm cameras through portholes from their location inside the Russian Zvezda Service Module. These photos will be thoroughly scrutinized by imagery experts back at Mission Control in Houston to look for any signs of damage to the heat shield before NASA commits Discovery to the scorching heat of reentry and a return landing back on Earth.

Earlier STS 131 related articles by Ken Kremer:

Antenna Glitch hinders Data Flow from Inspection of Discovery

Discovery Dazzles with Two Dawns in One Day

Discovery Unveiled on Easter Sunday to the Heavens Above

Countdown Clock Ticking for Discovery Blast off on April 5

Soyuz Blasts off with Russian American Crew for Easter ISS arrival

Posted on by Nancy Atkinson

Newly Discovered Asteroid Will Pass by Earth April 8

Orbit of asteroid 2010 GA6. Image credit: NASA/JPL

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Good to know the Spaceguard teams are keeping an eye out for us. The eagle-eyed observers at the Catalina Sky Survey have spotted an asteroid which will pass relatively close to Earth this Thursday, April 8, 2010 at 23:06 U.T.C. (4:06 p.m. PDT, 7:06 pm EDT). But it should pose no problem, as at the time of closest approach asteroid 2010 GA6 will be about 359,000 kilometers (223,000 miles) away from Earth – about 9/10ths the distance from to the moon. The asteroid is approximately 22 meters (71 feet) wide.

“Fly bys of near-Earth objects within the moon’s orbit occur every few weeks,” said Don Yeomans of NASA’s Near-Earth Object Office at the Jet Propulsion Laboratory in Pasadena, Calif.

This one, however, is a bit bigger than other recent asteroid alerts NASA’s Near Earth Observation program has issued. In November 2009, a 7-meter asteroid called 2009 VA came within 14,000 km (8,700 miles) of Earth and in January, 2010 AL30 was about 10-15 meters long and came within only 128,000 km (about 80,000 miles).

NASA’s NEO program, also called Spaceguard, discovers these objects, characterizes a subset of them and plots their orbits to determine if any could be potentially hazardous to our planet.

So while you’re waiting for this one to pass by you can read Don Yeoman’s top ten favorite asteroid facts.

The Catalina telescope is in Tucson, Arizona.

For more information about asteroids and near-Earth objects, visit NASA’s Asteroid Watch page.

Posted on by Nancy Atkinson

Double Spaceship Sighting Alert!

The ISS, as seen from space shuttle Endeavour on the STS-130 mission. Credit: NASA

Since this perhaps the fourth-to-the-last space shuttle flight, right now is a great opportunity to see the marvelous sights of International Space Station and space shuttle Discovery flying close in tandem. Depending on where you live, Tuesday evening or early Wednesday morning should provide a wonderful opportunity to see the two as the shuttle prepares to dock at 7:44 GMT (3:44 a.m EDT) on April 7, 2010.

Before docking, the two spacecraft will be seen as separate but closely-spaced points of light. The ISS is bigger, so will appear as the brighter object leading the smaller Discovery as they move across the sky. After docking, the ISS will be brighter yet with the additional surface area provided by the docked shuttle. Of course, your viewing ability will depend on cloud cover.

To find out if you’ll be able to see spaceships in your area, there are a few different sites to check out:
Continue reading “Double Spaceship Sighting Alert!”