Run, Don’t Walk, To Your Nearest Moon Base

An 'exoskeleton' made of fiberglass rods and springs, developed by MIT. Image courtesy of Christopher Carr.

Running is more efficient than walking for humans wearing spacesuits on the moon, according to a new study. A laboratory simulation of moonwalking found that pressurized spacesuits act as springs for our legs, and on the moon this effect is most pronounced during activity where the knee is bending at a greater angle, such as running. These findings may help NASA develop more efficient and comfortable spacesuits for future moon explorers, while also assisting research in prostheses for amputees. And who knows, maybe it could even promote the first lunar marathon run.

Because of the constriction of spacesuits and lower gravity, human movement is different on the moon than on Earth. This was evident during the Apollo missions where astronauts had a hard time bending over to pick up rocks or labored as they walked, but ran or bunny-hopped across the lunar surface with relative ease.

To simulate these conditions, researchers Christopher Carr and Dava Newman from MIT used an “exoskeleton” made of fiberglass rods and springs and placed them on the legs of a research subject. This exoskeleton was developed in large part by another MIT researcher, Dr. Hugh Herr in his study of prosthetics for amputees.

“We demonstrated that exoskeleton legs are similar to space suit legs, and that space suit legs act like springs due to the pressure of the space suit,” Carr told Universe Today. “Because of this, space suits support their own weight, but are hard to bend, making it difficult to carry out basic actions like picking up a tool from the ground.”

Carr is looking at ways to optimize the balance between stiffness and weight support to help the locomotive abilities for space-suited lunar astronauts. Less stiff spacesuits would enable easier ground access, but if they aren’t stiff enough, the suit will not support its own weight. Carr said the balance might be achieved with a change in the geometry of the space suit legs.

What else does this mean for future lunar exploration? During the Apollo missions there was a requirement of a walk-back constraint. Imagine a circle with an astronaut at the center, with the radius of the circle determined by how far you could walk while using only an emergency oxygen supply. This radius would specify how far away an astronaut could travel from their ‘base’, so that if a failure occurred he would be able to return safely. Now that we know running is more efficient than walking, said Carr, we should be able to base this constraint on running, allowing astronauts to travel further from their ‘base’, whether that base is their main habitat, or a pressurized rover.

Carr said he was somewhat surprised by their findings using the exoskeleton.

“I had not expected the forces imposed on the body by the exoskeleton to be so similar to the space suit knee joint,” he said.

They also used a simulated lunar gravity (1/6th of Earth’s) where the research subject wearing the exoskeleton was supported by cords attached to the ceiling by springs. “In this case, the subjects were even more efficient using an exoskeleton than walking or running without the exoskeleton,” said Carr. “We knew this was a possibility, but the proof is in the pudding.”

From this research it’s interesting to speculate about future athletic endeavors on the Moon. Running might be the sport of choice for lunar inhabitants, and the possibilities abound for lunar basketball. “Lower gravity might mean big jumps,” said Carr. “Even though our muscles will contract really fast, and thus will not be very efficient, we should be able to jump with a higher vertical velocity on the moon, maybe 30-50% faster than on Earth based on prior studies. Because gravity is 1/6 of Earth, that velocity will allow us to jump many times higher. We had better design those lunar habitats with high ceilings.”

Journal Reference: Science Direct

Traffic Jam at the Space Station

Space traffic control will be needed at the International Space Station as a busy timeframe of missions and resupply flights continue for our home port in space. In a choreographed ballet of spaceships, ESA’s first Automated Transfer Vehicle (ATV) resupply ship and NASA’s Space Shuttle Endeavour are scheduled to liftoff on March 9 and 11, respectively, to dock with the ISS, while a third – Russia’s Soyuz – is due to arrive early in April. The heavy traffic comes just a few weeks after Space Shuttle Atlantis left the ISS on February 18, delivering the Columbus science lab to the station. With Endeavour scheduled to be docked to the ISS from March 13 – 24, the ATV must patiently wait in a “parking orbit,” travelling in a holding pattern below the station, and will then dock after the shuttle leaves.

As of now, everything is “go” for all three flights. Endeavour will ferry Japan’s Kibo science lab to the ISS, along with the Canadian Space Agency’s two-armed robotic system called Dextre. STS-123 is commanded by Dominic Gorie with Greg Johnson serving as pilot. The crew also includes Mission Specialists Rick Linnehan, Robert Behnken, Mike Foreman, Garrett Reisman and Japanese astronaut Takao Doi. Reisman will stay aboard the station, trading places with ESA astronaut Léopold Eyharts, who has been on board since Atlantis’ February mission to the ISS.

But in the meantime, the ATV will be waiting in the wings to deliver its cache of supplies to the station. “After launch, we will have an opportunity to show and demonstrate to our ISS partners exactly what the ATV is capable of doing,” said Alberto Novelli, ESA’s Mission Director for the ATV. “And we can place ATV in a holding orbit for an extended period, if necessary, before doing the final, actual docking,”.

Space Traffic Control.  Image Credit:  ESA
The ATV is scheduled to dock on March 29. However, if there are any slips or technical issues to delay the ATV’s docking, there are only four subsequent days on which the actual docking can take place. One limitation causing this is illumination conditions: astronauts on board the station must not be blinded by sunlight while monitoring the approaching vehicle’s progress.

Another limitation is caused by more traffic: Russia’s Progress M-63, docked since February 7, will undock on April 7 and a new Soyuz arrival and docking is scheduled for April 10. Additional limitations on the ATV docking window could come about if Endeavour’s launch is delayed or if its docked phase extends past March 27. For example, last month, Atlantis’ docked phase was extended by one day to facilitate the installation of Columbus.

“It’s an extraordinary time. While we face a tight window, the intense activity at the ISS these weeks – with European, American, Russian, Canadian and Japanese payloads or vessels in flight – highlights the fantastic international character of the Station,” said Bob Chesson, ESA’s manager for Human Spaceflight Operations.

Check out the ATV blog to follow the mission live, and NASA’s STS-123 launch blog.

Original News Source: ESA Press Release

That Dark Stuff, Matter and Energy

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Being a very hands-on-type person, I have a hard time wrapping my brain around the concepts of dark energy and dark matter. These are invisible, hypothetical stuffs that cosmologists tell us make up a combined 96% of the universe. These ubiquitous substances are unlike anything we’re familiar with. They don’t emit or reflect enough electromagnetic radiation to be detected directly, but their presence is inferred by the gravitational effect they have on everything we can see. So, scientists are trying to determine if dark energy and dark matter are really there, and if so, what they’re made of. A couple of studies have come out recently dealing with dark energy and dark matter. One study released says that what we think might be dark energy may only be tiny whiskers of carbon materials, formed in the early days of the universe. And a new experiment tried to determine if dark matter is made of particles called axions.

Andrew Steele and Marc Fries from the Carnegie Institution say that what we thought was dark energy may just be a haze of tiny whiskers of carbon, strewn across the universe and perhaps those whiskers — and not dark energy — would dim faraway objects such as supernovae. Scientists proposed the dark energy hypothesis a decade ago in part to explain the unexpected dimness of certain stellar explosions.

The researchers report discovering an unusual new form of carbon in minerals within meteorites dating from the formation of the solar system. They believe the “graphite whiskers� were likely produced from hot, carbon-rich gases that formed near stars and were blown into interstellar space by solar winds or supernovae. A thin haze of the whiskers in space would affect how light of different wave-lengths pass through space. The researchers postulated that light of near-infrared wavelengths would be particularly affected—the same wavelengths whose dimming first led to the dark energy model.

Things like these graphite whiskers have been proposed previously to possibly explain observations where dimming appeared, but the presence of any types of materials in space has never been confirmed previously, said Steele and Fries. With their discovery in the meteorite, the pair added, researchers can test the whiskers’ properties against theories and observations.

Dark matter: To make hypothetical matter, you might just need a little dash of hypothetical particles. How about axions? Axions are theoretical particles that have a small mass, about 500 million times lighter than an electron. Additionally, according to theory, an axion should have no spin. A group from the Fermi National Accelerator Laboratory (Fermilab) in Batavia, Illinois designed an experiment to try to find axions.

They set up a magnetic field and shot a lazer into it. A “wall� was placed in the middle of the magnetic field as well. It was thought that the magnetic field would possibly change some of the photons from the laser into axions. The wall would stop the photons, but the axions would emerge on the other side.

They tried four different configurations of their system, unfortunately, the experiment found no evidence of new particles. But, they were able to exclude some constraints or regions where this type of particle could or could not exist.

And the data from the Fermilab experiment is still being examined. Scientist William Wester is optimistic about the role he and his colleagues are playing. “We did a serious measurement and excluded a region,� he says. “If our small experiment helps heighten awareness and leads to more experimental efforts, even using other techniques as well, it will be a huge benefit that we have done this.�

The group believes that maybe with a stronger magnetic field, it might be worth trying their experiement again.

This brings to mind something that I heard cosmologist Michael Turner say: “If I succeed in confusing you about dark matter and dark energy, then I will have brought you up to where the experts are.â€?

Original News Sources:
World Science
Physorg.com release

Earth and Moon, As Seen From Mars

This picture was released a couple of days ago, but since it’s so special, it deserves a post on Universe Today. And besides, everyone secretly likes to look at pictures of themselves. And this is a picture of us: it’s the Earth and the moon, as seen from Mars. From the Mars Reconnaissance Orbiter, to be exact, and it was taken by the HiRISE Instrument on board, the High Resolution Imaging Science Experiment. That’s the same camera that gave us the images of the avalanche on Mars, so the capabilities of this instrument are quite spectacular. This image was snapped back in October 2007, from a distance of 142 million kilometers, and if you look closely, you can make out a few features on Earth.

The west coast outline of South America is at lower right on Earth, although the clouds are the dominant features. In fact, the clouds were so bright, compared with the Moon, that they almost completely saturated the filters on the HiRISE camera. The people working on HiRISE say this image required a fair amount of processing to make a such a nice-looking picture. Yes, I agree, we are looking quite nice.

The phase angle is 98 degrees, which means that less than half of the disks of the Earth and Moon have direct illumination from the sun; that’s the reason we only see about half of each object. The scientists working on HiRISE say they would be able to image the Earth and moon when they are fully illuminated, but only when they are on the opposite side of the sun from Mars. However, then the distance would be much greater and the image would show less detail.

At this distance, this HiRISE image has a scale of 142 km/pixel, giving the Earth diameter about 90 pixels and the Moon diameter 24 pixels.

And now, back to the target that HiRISE was originally designed for: Mars. Here’s a very colorful (and false color) image that highlights the different minerals in Nili Fossae on Mars, one of the potential landing sites for the Mars Science Laboratory rover. From the CRISM instrument, the on-board spectrometer, scientists can discern that this area on Mars contains iron and magnesium, minerals that also contain water.
Nili Fossae on Mars.  Image Credit: NASA/JPL/University of Arizona

Original News Source: HiRISE Web page

A One-Way, One-Person Mission to Mars

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Will humans ever really go to Mars? Let’s face it, the obstacles are quite daunting. Not only are there numerous, difficult, technical issues to overcome, but the political will and perseverance of any one nation to undertake such an arduous task just can’t be counted on. However, one former NASA engineer believes a human mission to Mars is quite doable, and such an event would unify the world as never before. But Jim McLane’s proposal includes a couple of major caveats: the trip to Mars should be one-way, and have a crew of only one person.

McLane worked at NASA for 21 years before leaving in 2007 to work for a private engineering firm. Being able to look from afar at NASA’s activities has given him a new perspective, he says.

But McLane was still at NASA when he originally had an idea for a one-way, one-person mission to Mars. He calls his proposal the “Spirit of the Lone Eagle,” in deference to Charles Lindbergh’s solo flight from New York to Paris in 1927.

McLane’s idea came from his acquaintance with a Russian cosmonaut. “I noticed the cosmonaut seemed to be a slightly different type of person than the American astronaut,” McLane said. “Cosmonauts are primarily pilots, and like test pilots, they are very focused on getting the job done. The current American astronauts are picked for things such as their speaking ability and social skills, and most of them have advanced degrees. But the cosmonaut struck me as an adventurous, get-things-done-type person, like our original astronauts back in the 1960’s.”

A return to the “get it done” attitude of the 1960’s and a goal of a manned landing within a short time frame, like Apollo, is the only way we’ll get to Mars, McLane believes. Additionally, a no-return, solo mission solves many of the problems currently facing a round-trip, multiple person crew.

“When we eliminate the need to launch off Mars, we remove the mission’s most daunting obstacle,” said McLane. And because of a small crew size, the spacecraft could be smaller and the need for consumables and supplies would be decreased, making the mission cheaper and less complicated.

While some might classify this as a suicide mission, McLane feels the concept is completely logical.

“There would be tremendous risk, yes,” said McLane, “but I don’t think that’s guaranteed any more than you would say climbing a mountain alone is a suicide mission. People do dangerous things all the time, and this would be something really unique, to go to Mars. I don’t think there would be any shortage of people willing to volunteer for the mission. Lindbergh was someone who was willing to risk everything because it was worth it. I don’t think it will be hard to find another Lindbergh to go to Mars. That will be the easiest part of this whole program.”

And like Apollo, such a mission would stimulate new technology and reinvigorate science. McLane feels a mission to Mars should be international in scope, encompassing contributions from multiple nations to represent a milestone for the whole human race.

Mars mission.  Image Credit:  NASA

“I think people have forgotten how exciting the Apollo program was, and this would bring that excitement back,” he said. “And it wasn’t just here in the US; the whole world was excited. This enthusiasm would be the greatest effect of a program that places a man on Mars, over and above anything else, whether it makes jobs, or stimulates the economy, or creates technology spinoffs. We’re all humans and the idea of sending one of our kind on a trip like that would be a wonderful adventure for the entire world. The whole world would get behind it.”

And the whole world would be watching, said McLane, so it wouldn’t be as if the lone astronaut would be completely by himself. “You would have constant communication,” he said. “The astronauts on the International Space Station have an army of people on earth keeping track of what they are doing. They really have no peace. Somebody is constantly planning and monitoring their activities. I don’t think being lonely will be much of a problem on a mission to Mars.”

Of course McLane’s hope is the solo astronaut would be joined by others shortly in the future. Orbital mechanics provides a desirable launch window from Earth to Mars every 26 months. “This person wouldn’t be there by himself for very long. It’s just returning home that would be impossible,” he said. Another option McLane has offered is a one-man and one-woman crew, possibly creating an Adam and Eve-type situation.

Unmanned landers would carry living accommodations, supplies and communication equipment to Mars’ surface before the human mission would even launch. The best location on Mars would be a low, sheltered area, perhaps at the bottom of a canyon, which would provide protection from radiation and weather, as well as the highest possible atmospheric pressure.

While technical issues abound for even the simplest human mission to Mars, McLane says technical issues didn’t deter the Apollo program, and they shouldn’t deter a mission to another planet.

“I can remember during the early days of the Apollo program, there were even many more technical issues than we face today in going to Mars,” said McLane. “People don’t realize that, or have forgotten that fact. Several things were tremendous unknowns back then, any one of which could have been a showstopper for a human moon landing.”

McLane said the early designers of the Apollo spacecraft gambled that in 3 or 4 years, high powered transistors and small guidance computers would be developed. That was the only way the spacecraft would be lightweight enough to land on the moon. “It was almost science fiction, but someone thought it could be done in just a few years, and sure enough the technology was perfected in time to make the mission possible,” he said.

James C. McLane.  Image Credit:  courtesy James McLane
Image: Jim McLane during his career at NASA.

While Apollo 11 astronaut Buzz Aldrin and noted author and physicist Paul Davies have also advocated a one-way trip to Mars, in our risk-averse society most people look askance at such an idea.

Even though explorers in the past traveled, for example, to the south or north pole, knowing they might never return, and thousands of immigrants moved to the US in the 18- and 1900’s, knowing they would never see their homeland again, the human psyche has seemingly changed enough that a one-way ticket off the planet is not acceptable. According to psychologist Molly Dooley from Springfield, IL, it might take a major crisis on Earth for humans to seriously consider such a mission. “Usually it’s the disenfranchised that are willing to take those kinds of risks,” she said. “When our present situation no longer works for us, we become more willing to take risks. The difference between the folks who are interested and those who aren’t is their attachment to their current situation.”

McLane says the main reason NASA hasn’t been able to focus on a human mission to Mars is simple: NASA doesn’t get nearly enough money. “This has been the case for many years,” he said. “They didn’t get enough money to fix problems with the shuttle, and they’ve always been chronically short of money. How we fund NASA is a big handicap, since every year, NASA has to go begging to Congress for funds and justify their budget. The Chinese space program, on the other hand, has an advantage in that they budget their projects in five-year increments. If we really want to go somewhere, we’ll have to change how NASA gets its money.”

But McLane thinks NASA is at fault for not even considering a one-way mission to Mars. “For over forty years they’ve studied all sorts of options, but haven’t admitted to ever looking at a one-way mission to Mars,” he said. “We shouldn’t be stuck on this rock forever. I believe it’s in our human nature to try to go somewhere else, and we’ve almost worn this world out. I think now is the time to reach out and go somewhere else to start with a clean slate. There is no reason not to try.”

Looking Down the Barrel of A Gamma Ray Burst

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A team of astronomers from the University of Sydney in Australia have been keeping an eye on a binary star system called Wolf-Rayet 104, located in the constellation Sagittarius. Wolf-Rayet stars are hot, gargantuan, older stars that are losing their masses, and astronomers consider these stars as ticking bombs: they could go supernova at any time within the next few hundred thousand years. That’s a relatively short fuse for astronomers. Images of this system from the Keck Telescope show an almost perfect spiral nebula formed by the two stars orbiting each other as they each blow off streams of gas. The way this system is spinning caught the eyes of these astronomers, who say Earth could be in the line of fire when the system blows.

Usually, a supernova explosion would be harmless at interstellar distances like the 8000 lightyears that this system lays from Earth, and it would just provide an impressive show for stargazers. But astronomers say the only way WR 104 could appear as an almost perfect spiral is if those of us on Earth were looking down the spin-axis of the system. Astronomer Peter Tuthill says that sometimes, supernovae focus their energy into a narrow beam of very destructive gamma-ray radiation along the axis of the system. A gamma-ray burst is a super-duper supernova that sometimes happens to massive stars, like the ones in WR 104.

As of now, no one can say for sure when the system will go supernova, or how massive and powerful the explosion might be. But the way these two stars are spinning about each other has astronomers thinking this system won’t provide just a run-of-the-mill explosion.

And an intensive gamma-ray burst at that distance could possibly be harmful to life on Earth.

But right now, this is all speculation, and more study on this system is needed before anyone needs to get worried. And this is all definitely very fascinating.

11 image stack.  Image Credit:  University of Sydney
“I used to appreciate this spiral just for its beautiful form, but now I can’t help a twinge of feeling that it is uncannily like looking down a rifle barrel,” says Dr. Peter Tuthill.

With a sequence of 11 different images, the astronomers were able to portray how the spiral nebula of this system is rotating in a circle every 8 months.

Original News Source: University of Sydney Press Release

Latest Mars Images Round-up

With three orbiters and two rovers currently at Mars, there are always interesting images coming back from the Red Planet. Here’s a round-up of the latest images from the five different spacecraft. First up is a fascinating image from the Mars Odyssey spacecraft of dust devil tracks. It’s amazing just how many tracks there are in just this one image. Martian dust devils can be up to fifty times as wide and ten times as high as dust devils seen on Earth. This image was taken by Odyssey’s Thermal Emission Imaging System (THEMIS), and shows an area in the south polar region, just east of Daly Crater. Resolution is about 17 meters per pixel. Original Image link.


NASA’s Mars Exploration Rover Spirit has this view northward from the position at the north edge of the “Home Plate” plateau where the rover will spend its third Martian winter. And no, that’s not a pool of water in the image. It’s just rippled sand in the “El Dorado” sand dune field, and the image is shown in false color.

Husband Hill is on the horizon. Spirit used its panoramic camera (Pancam) to capture this image during the rover’s 1,448th Martian day, on January 29, 2008.
Original image link.

This view from the Opportunity rover shows a close-up of bedrock from the inside of Victoria Crater, where the rover is currently studying a stratigraphic layer of rocks. This area is informally named “Lyell,” which is the lowermost of three layers the rover has examined at a bright band around the inside of the Crater.

Opportunity used its panoramic camera (Pancam) to capture this image with low-sun angle at a local solar time of 3:21 p.m. during the rover’s 1,433rd Martian day, on February 4, 2008. This image, too, is in false color to highlight the ripples and bands in the bedrock.
Original Image link.

Mars Express Candor Chasma.  Image Credits: ESA/ DLR/ FU Berlin (G. Neukum)
ESA’s Mars Express took snapshots of Candor Chasma, a valley in the northern part of Mar’s huge canyon, Valles Marineris, as it was in orbit above the region on 6 July 2006.

The High Resolution Stereo Camera on the orbiter obtained the data,with a ground resolution of approximately 20 m/pixel. Candor Chasma lies at approximately 6° south and 290° east.
Original Image link.

HiRISE Volcanic Vent.  Credit: NASA/JPL/University of Arizona

This image taken by the Mars Reconnaissance Orbiter (MRO) shows a volcanic vent. A volcanic vent is an opening in the crust of a planet that emits lava (molten rock) and volcanic gases. The rough texture of the plains surrounding the vent iindicates that it is lava.

There is a large number of snake-like features emanating from the vent. The parallel lines that outline the features are levees, which mark the edges of channels that carried molten lava. As lava flows, it moves slowest at its edges and bottom because the lava sticks to the non-flowing rocks, and as the lava slows, it cools off and hardens.

Levees form when the sides harden but the center of the flow keeps moving. As the eruption episode ends, and the lava drains, the center is left lower than the sides producing these high-standing structures. Of course, these lava flows are very, very old.
Original Image page.

Help Map Our Dark Skies

Have you ever really seen the night sky — a sky without any pollution from artificial light sources? Over half of Earth’s population lives in urban areas, and have probably never seen a rich, dark sky full of millions thousands of stars. Not only does light pollution make it harder for amateur and professional astronomers to observe the night sky, but it affects other living things as well. Birds and other animals that are nocturnal can become disoriented from constant artificial light.

You can help track how light-polluted our skies have become by participating in the GLOBE at Night Program. All you need to do is go outside and look for the constellation Orion and compare your view with sky charts provided by GLOBE and report your findings. The programs runs from now until March 8.

The GLOBE website provides you with information and links on how to find your latitude and longitude and how to find Orion. You then match your nighttime sky to one of their magnitude charts and report your observation. Then you can compare your observation to thousands around the world. Last year about 8,500 people participated in this event. Phil and Emily have already posted on this, but Universe Today is now joining in to help GLOBE have their night sky biggest event yet.

Also available from the GLOBE site are downloadable family activity packets and information for teachers, offered in several different languages. Take this opportunity share the wonders of the night sky with young children while helping to track light pollution. It will only take a few minutes.

New NASA Animation Lets You Land on the Moon

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Using new high resolution terrain mapping data obtained by the Deep Space Network, NASA has created some new animations that take viewers to the Moon’s south pole. The videos include a flyover of Shackleton Crater and a very nifty animation of descent to the lunar surface of a future human lunar lander.

“I have not been to the Moon, but this imagery is the next best thing,” said Scott Hensley, a scientist at JPL and lead investigator for obtaining the data. “With these data we can see terrain features as small as a house without even leaving the office.”

Here’s the descent and landing animation. Make sure you watch to the very end, because the ending is the most impressive part, when you realize where you’ve landed.

The rim of Shackleton Crater is considered a candidate landing site for a future human mission to the moon.

And there’s more:

The mapping data collected indicate that the region of the Moon’s south pole near Shackleton Crater is much more rugged than previously understood. Here’s an animation of a flyover of the lunar south pole

Another animation shows the amount of sunlight falling on the Moon’s south pole during one lunar day. Notice that the interior of some craters remain almost completely dark — no sunshine ever strikes these areas — and some scientists feel there could possibly be water ice inside these craters.

To create these animations scientists targeted the Moon’s south polar region three times during a six-month period in 2006, using Goldstone’s 70-meter (230-foot) radar dish. The antenna, three-quarters the size of a football field, sent a 500-kilowatt-strong, 90-minute-long radar stream 373,046 kilometers (231,800 miles) to the moon. The radar bounced off the rough-hewn lunar terrain over an area measuring about 644 kilometers by 402 kilometers (400 miles by 250 miles). Signals were reflected back to two of Goldstone’s 34-meter (112-foot) antennas on Earth. The roundtrip time, from the antenna to the Moon and back, was about two-and-a-half seconds.

For more images and animations go to NASA’s Moon Exploration page.

Earth Life Forms Ejected on Asteroid Impact Could Survive and Return Again

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Does this mean that, perhaps, we can go home again?

If an asteroid or comet impacted Earth, the resulting ejection of materials could contain life forms. According to a study published in the journal Astrobiology, these life forms could survive and then seed another planet or moon with life. Additionally, Earth could also be re-seeded with life by those same life forms.

Ah, there’s no place like home.

If rock fragments containing embedded microorganisms were ejected into space, at least some of those organisms might survive and reseed Earth or seed another planetary surface able to support life. This scenario, which is called lithopanspermia was examined in studies called systematic shock recovery experiments designed to simulate this type of situation where microorganisms are transported between planets via meteorites.

The researchers sandwiched dry layers of three kinds of biological test ingredients, including bacterial endospores, endolithic cyanobacteria, and epilithic lichens, into rocks analogous to rocks from Mars. They then simulated the shock pressures Martian meteorites experienced when they were ejected from Mars and determined the ability of the organisms to survive the harsh conditions.

The organisms are hardy examples of microbes that can withstand extreme environmental stress and represent potential ‘hitchhikers’ within impact-ejected rocks.

“Given that impacts have occurred on planetary bodies throughout the history of our solar system,” says Sherry L. Cady, PhD, Associate Professor in the Department of Geology at Portland State University, “the hypothesis that life in rock could have been transferred between planets at different times during the past 3.5 billion years is plausible.”

And not only is it plausible that Mars rocks could be transferred to Earth and vice versa, but ejected rocks from Earth could possibly return and land back on their home planet. Given the contemplation of the destruction of life on Earth, it’s somewhat comforting to think that we could perhaps start over again from our own ingredients.

Original News Source: Astrobiology Press Release