Posted on by Nancy Atkinson

Happy Holidays in Space

space-station.thumbnail.jpg

NASA is encouraging Earthlings to send a holiday greeting to the members of Expedition 16 on board the International Space Station. NASA’s Homepage contains a link to send your holiday good wishes to the crew with pre-made e-postcards. The sentiment is nice, however the cards seem a little backwards.

One e-card has a picture of the ISS with a caption that says “The View From 220 Miles Up,” while another displays a waving EVA astronaut saying “Wish You Were Here.” These cards are supposed to be to the crew and from Earth, so perhaps more appropriate might be a picture of a snowy holiday scene or a majestic Earth landscape with the caption “Wish You Were Here, But Glad You Are Up There Furthering the Advances of Human Spaceflight.”

But take this opportunity to express yourself to the ISS crew.

And now on to more pressing news from the ISS:

Space shuttle Atlantis’ STS-122 mission to the space station has now been delayed to no earlier than January 10, 2008.

“Moving the next launch attempt of Atlantis to Jan. 10 will allow as many people as possible to have time with family and friends at the time of year when it means the most,” said shuttle Program Manager Wayne Hale. “A lot has been asked of them this year and a lot will be asked of them in 2008.”

Additionally, it gives engineers more time to understand the engine cutoff sensor problem that has kept the shuttle on the ground. An original launch of Dec. 6 was scrubbed when the sensors failed in a routine test during fueling of the shuttle’s external tank. The problem re-occurred in subsequent tanking test during countdown on Dec. 9, which caused NASA officials to decide to delay the launch until after the first of the year.

STS-122 will bring the Columbus science module to the station, the European Space Agency’s major contribution to the ISS. In addition to conducting three spacewalks to outfit the new science module, shuttle astronauts would also have done a fourth EVA to inspect a troublesome solar array rotary joint on the ISS’s power-providing solar panels that is contaminated with metallic shavings.

So instead ISS astronauts Peggy Whitson and Dan Tani will do that inspection on a spacewalk on Tuesday, December 18 starting at 6:00am EST. They will also look at another more recent power system problem that could be the result of a micrometeoroid or debris impact. On Dec. 8, two circuit breakers tripped, possibly the result of a space debris impact that might have damaged the mechanism that allows power and data to flow through the rotary joint used to turn the array about its axis.

For the SARJ problem, the starboard SARJ is locked in place because of excessive vibration and the metallic shavings and “bearing race ring” damage that were discovered during a quick inspection during the last shuttle mission. The SARJ has two drive gears and two redundant drive motors.

Whitson and Tani could install new bearings on the undamaged race ring and reposition the motors. The other option is to clean up the contamination and fix whatever is causing the problem.

“Once they have more data, they can make a better assessment of which of those approaches we should do, whether we should clean up the current race ring or just shift over,” ISS Commander Peggy Whitson said in a news conference from the station on Thursday morning. “I think either one’s doable,” she continued. “To me, in my mind, I think it would be probably, from an astronaut’s perspective, easier to just shift to the other race ring rather than trying to clean it up. But we don’t know yet how easy that’s going to be to clean up.”

Kirk Shireman, deputy manager of the space station program at the Johnson Space Center, said in a later news conference that no decisions will be made until engineers have more information about what might be causing the problem. The port-side solar arrays and that SARJ is operating normally.

“The idea is, we’ll conduct the EVA right now, the SARJ inspection and the BGA inspection, and we’ll learn what we need to learn,” Shireman said. “Then we’ll find the most opportune time to go fix it, not only the BGA but hopefully the SARJ. It really depends on how our analysis comes out. We’ll figure out exactly how long we can go with the BGA locked and the SARJ restrictions we have in place.”

Back to some holiday frivolity, since Tani would have returned to Earth with the STS-122 crew, which was originally scheduled to return home around the 19th of December, he wasn’t supposed to be on board the ISS during Christmas. Reporters inquired about his change of holiday plans and how gift arrangements were being handled. When asked, Commander Whitson declined to answer if all Tani would be receiving from her would be a lump of coal, saying she didn’t want to give away the surprise.

The astronauts said they have been hoarding foods like smoked turkey and other holiday-type goodies, saving them for Christmas dinner, so it appears that Atlantis and STS-122 were supposed to deliver the holiday meal. However a Progress re-supply ship will be docking with the ISS on Christmas Day, and one of the first things to be unpacked are hamburgers and fresh tomatoes and lettuce. Since fresh foods are a rare commodity on board the station, an All-American burger will be a welcome holiday treat for the crew.

Expedition 16 has also recorded a holiday message to Earth. Watch it here

Original News Source: NASA Press Release, NASA TV

Posted on by Fraser Cain

More Evidence that Gliese 581 Has Planets in the Habitable Zone

2007-1214gliese.thumbnail.jpg

The discovery of Gliese 581 was one of the most exciting moments in extrasolar planetary researcher. Astronomers found an Earth-massed planet orbiting within the habitable zone of a distant star. This would mean that liquid water could be on its surface – and maybe life. Now there’s even more evidence that Gliese 581 is living up to the speculation. Astronomers have published two independent studies this week, claiming that there are least 2 Earthlike planets orbiting the star within the habitability zone.

The first team, led by Franck Selsis, computed the properties of planetary atmospheres at various distances from the star. As we’ve seen with Venus, Earth and Mars in our own Solar System, your distance from the star matters a great deal. Get too close, and the water is vaporized and blown out into space. Get too far away and your carbon dioxide can’t trap in enough heat to keep the planet warm. You want to be just right.

Selsis and his team calculated that the inner boundary of this habitable zone around Gliese 581 should be somewhere between 0.7 and 0.9 astronomical units (an AU is the distance from the Earth to the Sun). And the outer zone should be between 1.7 and 2.4 AU. At least one planet orbiting Gliese 581 falls within this range.

The second team used a different technique to calculate habitability. They studied a narrower region where Earth-like photosynthesis is possible. For the super-Earths thought to be orbiting Gliese 581, they calculated the sources of atmospheric CO2 (volcanos and ridges) and then the potential sinks through weathering. If a planet’s too old, if might not be active any more, and wouldn’t release enough CO2 to keep the planet warm.

Once again, the age of the planets, and therefore the amount of carbon dioxide, is within this region of habitability.

Thanks to this new research, the planets orbiting Gliese 581 are primary targets for future planet hunting observatories, such as ESA’s Darwin and NASA’s Terrestrial Planet Finder. These observatories should be able to directly measure the atmospheres of these planets, and determine if they harbour life.

A third paper on the topic has recently been accepted for publication in the journal Astronomy and Astrophysics. In this, another team of researchers have studied the long term orbits of planets going around Gliese 581. Here you want stability, without highly eccentric orbits that might cause extreme warm and glacial eras. Once again, the planets around Gliese 581 are surprisingly stable.

Things are looking really hopeful. Now we just need someone to uncancel the Terrestrial Planet Finder.

Original Source: Astronomy and Astrophysics

Posted on by Fraser Cain

Saturn’s Rings Could Be as Old as the Solar System

2007-1214rings.thumbnail.jpg

Although the Solar System is 4.5 billion years old, planetary scientists thought that Saturn’s famous rings formed much later. Maybe as recently as a few hundred million years ago. But new observations from Cassini have pushed those estimate back… way back. Maybe all the way back to the beginning of the Solar System. Saturn’s rings might be ancient, with ring material getting recycled for eons.

According to Larry Esposito, principal investigator for Cassini’s Ultraviolet Imaging Spectrograph at the University of Colorado, Boulder, earlier data gathered by NASA’s Voyager spacecraft in the 1970s, and later from the Hubble Space Telescope indicated that the rings were young. Maybe a comet shattered one of Saturn’s moons about 100 million years ago, generating the particles we see today.

But the new evidence from Cassini shows the the rings vary in age significantly; the rings are being constantly replenished and recycled.

“The evidence is consistent with the picture that Saturn has had rings all through its history,” said Esposito. “We see extensive, rapid recycling of ring material, in which moons are continually shattered into ring particles, which then gather together and re-form moons.”

“We have discovered that the rings probably were not created just yesterday in cosmic time, and in this scenario, it is not just luck that we are seeing planetary rings now,” said Esposito. “They probably were always around but continually changing, and they will be around for many billions of years.”

So how can Cassini tell that there’s new material being generated. Astronomers used to think that infalling meteoric dust should pollute the older rings, making them darker. But the new Cassini observations show that the ring system spreads the pollution around, diluting it. This is why the rings appear to be so pristine and young.

They observed how the ring material blocked light from distant stars. They were able to detect 13 objects in Saturn’s F ring, varying in size from 27 metres to 10 kilometres (30 yards to 6 miles). Since most of the objects are translucent, the researchers think they’re just temporary clumps of icy boulders.

They appear to come and go, clinging together and then breaking apart under Saturn’s strong gravity. Although the rings always look the same, they’re being constantly recycled.

Original Source: NASA/JPL News Release

Posted on by Fraser Cain

Deep Impact Has a New Target

2007-1214epoxi.thumbnail.jpg

It seemed like such a shame. NASA built Deep Impact to see what happens when you smash a refrigerator-sized object into a comet. Mission accomplished, science gathered. But what about the flyby part of the spacecraft? It captured images of the collision with Comet Tempel 1, and then flew on without a target. Well, NASA announced this week that it has a new target: Comet Hartley 2.

Oh, and we don’t call it Deep Impact any more. That was so 2005. Now it’s called EPOXI. And if that sounds like an acronym, you’re right. Here’s the full designation: Extrasolar Planet Observation and Deep Impact Extended Investigation.

EPOXI was originally supposed to meet up with Comet Boethin, but NASA astronomers lost sight of the comet. They lost a comet? Actually, they think it might have broken up into smaller pieces, which are now too small for detection. Unfortunately, this loss pushed back its next cometary encounter by two years.

So the spacecraft is now heading for Comet Hartley 2. If all goes well, it’ll reach the object on October 11, 2010, passing within 1,000 km (620 miles) of the nucleus. As a target for scientific observation, Comet Hartley 2 will do the job nicely. Just like Boethin, it has a small, bright nucleus.

While it’s making this journey, the spacecraft will point the larger of its two telescopes at nearby extrasolar planetary systems, and help gather additional data. It’ll be looking to study the physical properties of giant planets, search for rings and moons and planets as small as three Earth masses.

One intriguing mission will have EPOXI observe the Earth as if it’s an extrasolar planet, to help refine the techniques and data necessary to characterize future terrestrial planet discoveries.

EPOXI made a three-minute rocket burn on November 1st, 2007, putting it on course to reach Hartley 2. Before this encounter, it’ll make three Earth flybys, gathering the additional velocity it needs to reach its meetup with Hartley 2 in 2010.

Original Source: NASA/JPL News Release

Posted on by Fraser Cain

Year in Space 2008 Calendar

2007-1214yearspace.thumbnail.jpg

Well, it’s that time again to get organized. So why not do it while gazing at pretty pictures of space and learning history at the same time?

Once again, I’m happy to present the “Year in Space” desk calendar – a regular sponsor for Universe Today. This is a 144-page weekly calendar featuring images and information from the past, present, and future of space exploration and astronomical discovery. Universe Today readers are eligible for discounts ranging from 25% to 44%, with free shipping on all U.S. orders. Normally retailing for $15.95, “The Year In Space” is available to Universe Today readers for only $11.95; 2+ copies are $10.95 each; 10+ copies are $9.95 each; and 36+ copies are $8.95 each.

There is free standard shipping on all U.S. orders. For guaranteed Christmas delivery, order on or before December 17th and choose RUSH delivery for a small additional fee. (Non-US orders are shipped via International Priority Mail, but cannot be guaranteed for Christmas.) Order online at www.YearInSpace.com and select the “Universe Today” sponsor discount, or call (800) 736-6836 and mention the Universe Today discount.

Visit the website to preview the calendar and download a free hi-res poster of all 53 weekly images. With “The Year In Space” you can visit a new celestial destination every week while keeping track of your busy life on Earth!

Click here to visit the Year in Space 2008 website.

Posted on by Fraser Cain

Making the Case for Europa

2007-1214europa.thumbnail.jpg

Nick had an article last week about a new technique that might help scientists figure out just how deep the oceans on Europa are. Deep oceans with a thin crust might give a rover, or a submarine, a fighting chance to get down to that precious H2O, and sample it for evidence of life. Researchers are seriously discussing the benefits of exploring Europa at the annual meeting of the American Geophysical Union in San Francisco.

According to William McKinnon, a professor of Earth and Planetary Sciences at Washington University in St. Louis, Mo, “We’ve learned a lot about Europa in the past few years.

“Before we were almost sure that there was an ocean, but now the scientific community has come to a consensus that there most certainly is an ocean. We’re ready to take the next step and explore that ocean and the ice shell that overlays it. We have a number of new discoveries and techniques that can help us do that.”

What advances have been made?

There’s the research we talked about; how detailed observations of the Moon’s flexing under Jupiter’s intense gravity, as well as the magnetic variations can tell just how deep the ocean goes.

And new radar sounding techniques have been developed for other spacecraft that would be very useful at Europa. The high-resolution radar system installed on the Mars Reconnaissance Orbiter would be able to peer right through an ice shell on Europa, and give researchers a cross section of the ice. It would be able to locate liquid water under and within the shell, and put the controversy to rest forever.

Engineers are also working on future explorers, such as a project called Endurance, developed by Peter Doran, associate professor of Earth and Environmental Sciences, University of Illinois at Chicago and Stone Aerospace. They’ll be testing an exploration vehicle in Wisconsin in February 2008, and then in Antarctica.

This robotic explorer will be able to create three-dimensional maps of the subsurface lakes in Antarctica and even map out the biochemistry in the water. If there’s life there, Endurance will find it.

Obviously, sending a probe like this to Europa is a long, long way off. But people are chipping away at the problem on both ends. Scientists are making the case that Europa is one of the most enticing scientific targets in the Solar System. And engineers are working out the technologies that could actually make the discoveries.

The future for exploration on Europa is looking brighter every day.

Original Source: University of Texas at Austin News Release

Posted on by Mark Mortimer

Book Review: The Lunar Exploration Scrapbook

2007-1213lunar.thumbnail.jpg

The allure of toys like Lego lies with their nearly inexhaustible ways to combine elements into whatever the imagination desires. At one time, humanity’s voyage into space had a similar allure, particularly with the previous presidential mandate to land on the Moon. With this, imaginations went wild, as seen in Robert Godwin’s book, The Lunar Exploration Scrapbook – A Pictorial History of Lunar Vehicles. Showcased within are an amazing collection of ‘might-have-beens’ that epitomize the ingenuity and imagination of our species.

During the race to the moon, many people believed that landing a person was the first step to a great adventure. Their vision imagined a vibrant colony of humans living on the Moon who performed valuable daily tasks much like everyday life in a small town on Earth. They even hoped for further travels to Mars soon thereafter. In response to these visions, many industrial companies strove to identify, present and sell all sorts of aids and devices to realize this future. However, much guess work was involved. No one had been to the Moon, few support systems were finalized and space flight experience was seriously lacking on all fronts. Not surprisingly then, imaginations were at the forefront.

In memory of these heady times, Godwin’s scrapbook dusts off prints and specifications of many a proposed payload. Whether lunar direct or Earth orbit rendezvous, whether on the Saturn IC or its big brother the Nova, opportunities abounded. With these slim constraints, the hodgepodge of drawings, photographs and layouts clearly show the heady rush to adapt Earth culture to the Apollo program. Two main groups define the selections in the book. One group shows various types of lunar landers for the lunar orbit rendezvous. These structures could act as power supplies, base stations, research laboratories, or maintenance garages. The other group shows possible methods of mobility on the lunar surface. For example, a complete study, the MOBEV, ranged from a small hand controlled cart up to a three passenger manned mobile laboratory that could sustain the crew for 90days and over 3000 kilometres. But, this is certainly not an exhaustive list of what’s in the book. Many others, including an exoskeleton, Fleming’s lunar direct model and a single person rocket sled fill the pages. With these, this scrapbook provides a very clear idea of the range of thought and breadth of application planned for establishing people on the Moon.

However, this scrapbook contains much more than illustrations,. With either guess work or slim specifications, Godwin rebuilt many of the items using current 3-dimensional software drawings. Usually each item is shown as face-on, side and from overtop. Occasionally these software models get placed on a mock-up lunar surface, complete with a lunar-suited figurine. From these, it’s very easy for the reader to create a mental image of the configuration of the structure and its probable employment on the Moon. Also, by isolating vehicles or crafts on a pair of facing pages, Godwin’s effectively providing a synopsis of the item. Then by adding a few written paragraphs for each, he highlights any important distinctions and provides interesting numerical specifications and manufacturer notes. For example, a preliminary lunar lander employed a knotted rope for egress and ingress rather than a ladder, quite a novel idea. Thus, like a scrapbook, each pair of pages brings to life one particular special subject.

However, though a scrapbook has its fun elements, it also has drawbacks. In particular, there’s little cohesion or traceability. Though Godwin has tried to keep each item in a chronological order, inferences in one item refer to the design or specialisation of another. Thus, the reader will find it challenging to determine the evolutionary trend and will also find it difficult to follow threads. Thus calling this a scrapbook is very applicable.

And, though this scrapbook is great fun and will be greatly enjoyed by anyone who’s lived through the Apollo era, others may find it less enchanting. As mentioned, these designs were dropped as better ones were developed or functions not needed. Hence, many readers might find amusement but little practicality. Nevertheless, this scrapbook does capture the imagination of the designers and some very well thought out equipment. Thus, readers looking for a spark of imagination for their own design work would benefit in reading this book.

A surprising variety of responses are possible when asked for the design of a vehicle. Tracked, wheeled, exposed, and airborne, all are possible variants. So when NASA went looking for responses in the 1960s, there was an opportunity for imaginations to be freed. Many results are shown in Robert Godwin’s book, The Lunar Exploration Scrapbook – A Pictorial History of Lunar Vehicles. Who knows, maybe some of these will work themselves into NASA’s current plans to return to the Moon.

Read more reviews or purchase a copy online from Amazon.com

Posted on by Fraser Cain

Carnival of Space #33

2007-1213belts.thumbnail.jpg

I’m not only the Carnival of Space organizer, but I’m also a host.

This week, we’ve got the following stories of interest.

First up, Nancy Houser at A Mars Odyssey discusses the discovery of the Van Allen Belts.

The space shuttle’s day is nearly over, but Orion won’t get going until 2015. Mark Whittington talks about how NASA will close up that gap.

astropixie Amanda Bauer reminds us all about the upcoming Geminid meteor shower, peaking on Friday.

advancednano talks about what it might take to launch to magnetic sail spacecraft from the Earth.

MSNBC’s Cosmic Logs has this article about the upcoming shuttle launch of the European Columbus science laboratory.

Astroblog considers the discovery that two of Saturn’s moons look like flying saucers, and considers the implications for science literacy.

Steinn Sigurdsson is whispering rumours about discoveries from the Corot mission.

With the shuttle reaching the end of its life, Stuart Atkinson wonders why so many space advocates have turned against the shuttle. Admit it, you’re going to miss Atlantis and the shuttles when there’s only Orion.

Be careful with your predictions for the future of space tourism, warns the Space Cynics.

Astronomy Picture of the Day has this anelemma; that’s the figure-8 shape you get when you take a picture of the Sun every day throughout the year.

Pamela Gay reminds you that the Geminids are coming… the Geminids are coming!

Remember the Genesis Mission? Emily at the Planetary Society Blog gives an update on the scientific discoveries made so far.

Centauri Dreams reviews the thinking about solar sail technologies that could take advantage of the particles streaming off the Sun.

Hobbyspace has two articles about one topic: Commercial Orbital Transportation Services. There’s this one about Spacehab’s proposal, and another about Loral and Constellation Systems.

A Babe in the Universe continues her tour through the American Museum of Natural History. This week, it’s the Hall of Meteorites.

Will the Lagrange Points help future travelers explore the Solar System, and act as depots for trade and commerce? Colony Worlds has the story.

And finally, from here on Universe Today, may I suggest this interesting story about Europa’s oceans. Are they thick or thin?

Posted on by Nancy Atkinson

The Spirit Rover’s Big Discovery

spirit-silica.thumbnail.jpg

Amazingly, the two Mars rovers, Spirit and Opportunity, have been working diligently on the surface of the Red Planet for almost four years now. So far, Opportunity has grabbed most of the spotlight, finding evidence for past water on Mars within months after landing on the smooth plains of Meridiani Planum. While Spirit has been working just as hard, if not harder, climbing hills and traversing the rocky terrain of Gusev Crater, she hasn’t yet caused quite the stir that her twin has. But now, a recent discovery by Spirit at an area called Home Plate has researchers puzzling over a possible habitat for past microbial organisms.

What Spirit found is a patch of nearly pure silica, a main ingredient in window glass.

“This concentration of silica is probably the most significant discovery by Spirit for revealing a habitable niche that existed on Mars in the past,” said Steve Squyres, principal investigator for the rovers’ science payload.

The silica could have been produced from either a hot-spring type of environment or another type of environment called a fumarole, where acidic steam rises through cracks in the planet’s surface. On Earth, both of these types of environments teem with microbial life.

“The evidence is pointing most strongly toward fumarolic conditions, like you might see in Hawaii and in Iceland,” said Squyres. “Compared with deposits formed at hot springs, we know less about how well fumarolic deposits can preserve microbial fossils. That’s something needing more study here on Earth.”

Squyres said the patch that Spirit has been studying is more than 90 percent silica, and that there aren’t many ways to explain such a high concentration. One way is to selectively remove silica from the native volcanic rocks and concentrate it in the deposits Spirit found. Hot springs can do that, dissolving silica at high heat and then dropping it out of solution as the water cools. Another way is to selectively remove almost everything else and leave the silica behind. Acidic steam at fumaroles can do that. Scientists are still assessing both possible origins.

One reason Squyres favors the fumarole story is that the silica-rich soil on Mars has an enhanced level of titanium. On Earth, titanium levels are relatively high in some fumarolic deposits.

Meanwhile both rovers are hunkering down for another winter season on Mars. Spirit’s solar panels are currently coated with dust from the huge dust storm the rovers endured this summer, and Spirit will need to conserve energy in order to survive the low light levels during the winter.

“The last Martian winter, we didn’t move Spirit for about seven months,” said John Callas, project manager for the rovers. “This time, the rover is likely to be stationary longer and with significantly lower available energy each Martian day.”

I’m keeping my fingers crossed for another solar panel cleaning windstorm event, which has happened previously, giving the rovers a boost in power.

Original News Source: Jet Propulsion Laboratory News Release