Posted on by Nancy Atkinson

Two New Kinds of Moon Rocks Found

Chandrayaan-1 3D color photo sent by the Moon Mineralogy Mapper. Credit: ISRO

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Scientists analyzing data from the Moon Mineralogy Mapper instrument or M Cubed, on the Chandrayann-1 spacecraft found two different kinds of never-before-seen lunar rocks – one hidden in a basin on the far side of the Moon and the other staring right at us on the near side. Just four minerals — plagioclase feldspar, pyroxene, olivine, and ilmenite — account for 98-99% of the crystalline material of the lunar crust, but the composition of these newly found rocks are two different kinds of spinels, a magnesium spinel and a chromite spinel. The composition and location of these new rock types are extremely puzzling, and lunar scientists are trying to determine more details about these mysterious Moon rocks.

Universe Today talked with Dr. Carle Pieters from Brown University who is the Principal Investigator for M Cubed as well as Dr. Jessica Sunshine from the University of Maryland, a co- investigator with the project.

Universe Today: Dr. Pieters, tell us about the newly found rocks on the far side.

Dr. Carle Pieters: The rock type on the far side of the Moon that is so unusual is a magnesium spinel, which typically has iron, magnesium, and aluminum oxide. In looking in detail at the spectral properties of the Moscoviense Basin on the far side — and in particular the material along the inner-most ring of this basin — we noticed there were a few little areas that were spectroscopically unusual. So, of course we investigated those in more detail. We saw three primary different compositions, and two we understand and had seen elsewhere, and they are rich in iron bearing minerals called pyroxene and olivine, and we saw small areas of these that are widely separated.

But then the third kind of mineral, the magnesium spinel, we had never seen before on the Moon, and what is interesting is not only is there an unusual abundance of this particular mineral, but it also has a lack of the pyroxenes and olivines that we see elsewhere. So there are several mysteries that are interwoven here. One, is why do we have a concentration of this spinel mineral and however it got concentrated in this area, why aren’t the other minerals that we are familiar with also there, because they are not.

So this is a big mystery and it is a very exciting one because now we have to reexamine our understanding of the character of the lunar crust, in particular to the depths that might have been tapped by this enormous basin and that we are now looking at as exposed on the surface.

Universe Today: So, what does this tell you about this region on the Moon?

Pieters: Not only are these unusual areas compositionally, and they are only about a kilometer or two in size, but in every method we’ve been able to look at thus far, in every wavelength and resolution, they have no other distinguishing properties. Typically, on the Moon to indentify an usual composition we look for a fresh crater that has excavated and exposed material on the surface of the Moon. These areas have no fresh craters, no disturbance at all across their surface, even at the highest resolution that is seen with the LROC (Lunar Reconnaissance Orbiter Camera) instrument which measures a half a meter resolution.

These are old surfaces that have been undisturbed but have an extremely unusual composition. And even the space weathering that has occurred on the surface throughout the billions of years of history on the Moon has not erased their unusual compositions. So, they are unusual for the kind of compositions we see, but they are also unusual because they have no identifying property that allows us to identify them in our imagery which is quite unusual for features on the surface of the Moon.

In the dark mantle deposits of the Sinus Aestuum (left), deposits of chromite spinel light up like beacons (right), but the nearby Rima Bode has no spinel. Credit: Jessica Sunshine, University of Maryland

Universe Today: Now let’s move to the near side of the Moon, where Dr. Jessica Sunshine and her team went looking for unusual data.

Dr. Jessica Sunshine: One of the things I was asked to be in charge of was looking for anomalies, things that just didn’t look like the rest of the Moon. And of course you never know what’s going to happen under those circumstances. Carle had already discovered there seemed to be a magnesium spinel on the far side of the Moon and I went looking to see where else it could be. We found that the only place that we had anything that looked like the spinel mineral in the data we had was on the near side and it was an extremely large deposit in the middle of the central nearside, almost exactly dead center at zero-zero. And we started looking a little more carefully and realized that it wasn’t really the same kinds of things that Carle found, which truly was a new rock type on the far side of the Moon, but something really usual about the region.

We had already known the region was full of what we call dark mantle deposits or pyroclastic deposits, which is firefountaining deposits. This came from explosive eruptions of lava and gas over large areas of the Moon, about the size of Massachusetts. And we knew that three of them were there, it just turned out that one of them was compositionally different from the other ones, and in particular it had the kind of spinel which is a chromite, because it has chrome in it, and now we’re busy trying to figure out why this deposit is different from the one next door, and what does it mean. And we’re still working that process out as we speak.

Universe Today: What is it like to find something new like this on the side of the Moon that humans have been able to see for thousands of years?

Sunshine: Yes, I tend to title my talks on the subject something like, “Hidden in Plain Sight” because they are! It’s right there and I think this is a really fascinating part of this because we have been starring at the Moon, as humanity for millennia and if our eyes were slightly different we would see this one really dark spot in the middle of the Moon that is different from anywhere else.

Universe Today: What specifically about the Chandrayaan-1 spacecraft and the Mcubed instrument made these discoveries possible?

Sunshine: M Cubed collects data over a much broader range of light than our human eyes can. We can all see the rainbow, we’re all familiar with that, from blue to red, but there is light at shorter wavelengths, which we call ultraviolet, and particularly for this case, there is light at shorter wavelengths called infrared. M Cubed goes farther into the infrared than humans can see and it is there we are able to see diagnostic fingerprints of different kinds of minerals. So I suspect there are certain kinds of bugs who would look at the Moon and would have known these deposits are there because their vision goes into the infrared!

Universe Today: So, Dr. Pieters, does these new discoveries tell us there are still more mysteries to find on the Moon?

Pieters: Oh, absolutely! We’ve just barely scratched the surface here. This is thrilling from a spectroscapist’s point of view, of course, but also from someone who is trying to understand how planets work, and in particular how this wonderful small body in our neighborhood is telling us about the characteristics of crustal evolution and fundamental properties of planetary surfaces.

You can listen to a version of this interview on the 365 Days of Astronomy podcast and the NASA Lunar Science Institute podcasts

Posted on by Nancy Atkinson

Understanding the Unusual LCROSS Ejecta Plume

Solid impacts send debris to the side (left), whereas hollow impacts result in a high-angle ejecta plume (right). The LCROSS impact was an emptied rocket and acted like a hollow projectile. Figure shows parts of a high-speed image sequence from experiments made at the Ames Vertical Gun Range at NASA's Ames Research Center, Moffett Field, Calif. Image credit: Brown University/Peter H. Schultz and Brendan Hermalyn, NASA/Ames Vertical Gun Range.

LCROSS was an unusual mission, in that it relied on an impact in order to study a planetary body. Not only was the mission unusual, so was the ejecta plume produced by slamming a hollow Centaur rocket booster into the Moon.

“A normal impact with a solid impactor throws debris out more than up, like an inverted lampshade that gets wider and wider as it goes out,” said Pete Schultz, from Brown University and a member of the LCROSS science team. “But the configuration of a hollow impactor — the empty rocket booster — created a plume that had both a low angle plume but more importantly, also a really prominent high angle plume that shot almost straight up.”

This high plume elevated the debris enough so it was illuminated by sunlight, and could be studied by spacecraft.

Even though the plume wasn’t seen from Earth, as was advertised prior to the impact, it was seen by the both the LCROSS shepherding spacecraft and the Lunar Reconnaissance Orbiter. Using the spent Centaur was not so much by mission design as using what was available. But it turned out to be a great choice.

“I think we were quite fortunate,” Schultz told Universe Today in a phone interview this week. “I think another design, and we may have gotten a very different result. Not much debris may have come up into the sunlight and the plume would have been very temporary.”

In order for the debris to get high enough to come into sunlight, it had to rise up about a half mile above the bottom of the crater.

“To put this into perspective,” said Schultz, “we had to throw debris up twice the height of the Sears Tower, the tallest building in the US. Now the Moon has less gravity, so if we bring it back down to Earth and compare it, it is like trying to throw a ball to the top of the Washington Monument. So there is a lot of gravity to overcome, and it turns out that this impact did it because we used a hollow impactor.”

When the rocket booster hit and the crater began to form, the lunar surface collapsed and shot upwards – almost like a jet – towards the sunlight, carrying with it the volatiles that had been trapped in the regolith.

In order to figure out what the impact was going to look like, Schultz and his team, which included graduate student Brendan Hermalyn, did small scale impacts and modeling. Their tests were only done a couple of months before the actual impact, and used small half-inch projectiles into different surfaces.

“Most impacts, when we model them, we assume the impactors are solid,” Schultz said. “We did experiments, with both solid and hollow projectiles, and when we used the hollow projectile, we had a real surprise. We not only saw the debris moving outward, but also upward.”

“We really didn’t know exactly what we were going to see in the actual LCROSS impact, but our tests explained a lot,” Schultz continued, “explaining why we saw what we did and why we saw the plume for such a long time. If it had been coming out like an inverted lampshade or a funnel expanding, the debris would have come up and gone back down, and probably would have been done within about 20 seconds. Instead, it just kept on coming.”

But there were some expected moments. As the LCROSS shepherding spacecraft approached the lunar surface, Tony Colaprete and the team readjusted the exposures on the cameras and the team was able to actually see the surface of the Moon in the final seconds before impact.

“That was great,” Schultz said. “That means we got to see the crater, we were able to get an estimate on how big the crater was, and it made sense with what our predictions had said. But we were also able to see the remnants of this high angle plume still returning to the surface. This must have been shot almost straight up into space, and was now coming back to the Moon. We saw it as a very diffuse cloud, and saw the remaining portions of the regolith coming back down, like a fountain. To me, that was the most exciting part.”

Schultz said he was nervous during the impact.

“I have to confess, we were on pins and needles,” he said, “as this was something much bigger than the experiments of using half inch projectiles and we didn’t know if it was going to scale up. We were dealing with something that looked like schoolbus with no children aboard that was slamming into the Moon and we didn’t know if that was going to behave in the same way as our smaller models.”

And even though the plume did act like the models, there were plenty of surprises — both in the impact and what has now been discovered to exist in Cabeus Crater.

“We knew when it was going to hit the surface – we know how fast how we were going and where we were above the surface — and it turned out there was a delay before we saw the flash and that was really a surprise,” Schultz said. “It was about a half second delay and then it took about a third of second delay before it began to rise and get brighter. The whole thing took seven-tenths of a second before it began to get bright. That is hallmark of a fluffy surface.”

Schultz said they know that it was likely a “fluffy” surface from the experiments and modeling, and from comparisons with the Deep Impact mission, for which he was a co-investigator.

“One of the first things we realized was that this is not your normal regolith — what you usually think of for the Moon,” Schultz said. “We watched the flash, and we looked for what type of spectra we saw. The spectra has the fingerprints of the composition of the elements and compounds. We were expecting because of the low speed we actually wouldn’t get to see much. But instead we immediately got a couple of hits, we got to see a sudden emission of OH, which is a characteristic at this wavelength of a byproduct of heating of water. Then the next 2-second exposure was when things started emerging, the overall spectra got brighter which meant we were seeing more dust. But then we saw this big giant peak of sodium, just like a beacon, a very bright sodium line.”

And then there were two other lines that were very odd. “The best association we could find that is was silver,” said Schultz. “That was a surprise. Then all these other emission lines started emerging as more material got into sunlight. This suggests that we were throwing the dust into the sunlight, and the volatiles that had been frozen in time, literally, in the shadows of Cabeus were heating up and and being released.”

Some of these compounds included not only water and OH, but also things like carbon monoxide, carbon dioxide, and methane, “things that we don’t think of when we talk about the Moon,” said Schultz. “Those are compounds we think of when we think about comets, so now we are in a position that maybe what we are seeing at the poles are the result of a long history of impacts that bring with them a lot of this type of material.” (Read our interview with Tony Colaprete for more about the recent LCROSS results.)

But no one is sure how the Moon can hold onto these volatiles and how they end up in the polar craters.

To figure that out, Schultz said more missions to the Moon are needed.

“Even though the Apollo astronauts were there, we’re now finding things 40 years later that are making our heads snap from all this the new information,” Schultz said. “It goes to show you, you can visit and think you know a place, but you have to go back and maybe even live there.”

Schultz said that as an experimentalist, one can never feel smug, but seeing how the actual plume behaved just like their models, he and his team were very happy. “Experiments are letting nature teach you lessons and that is why they are very interesting to do. We are humbled almost daily.”

Posted on by Nancy Atkinson

Water on the Moon and Much, Much More: Latest LCROSS Results

An image of debris, ejected from Cabeus crater and into the sunlight, about 20 seconds after the LCROSS impact. The inset shows a close-up with the direction of the sun and the Earth. Image courtesy of Science/AAAS

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A year ago, NASA successfully slammed a spent Centaur rocket into Cabeus Crater, a permanently shadowed region at the lunar South Pole. The “shepherding” LCROSS (Lunar Crater Observation and Sensing Satellite) spacecraft followed close on the impactor’s heels, monitoring the resulting ejecta cloud to see what materials could be found inside this dark, unstudied region of the Moon. Today, the LCROSS team released the most recent findings from their year-long analysis, and principal investigator Tony Colaprete told Universe Today that LCROSS found water and much, much more. “The ‘much more’ is actually as interesting as the water,” he said, “but the combination of water and the various volatiles we saw is even more interesting — and puzzling.”

The 2400 kg (5200 pound) Centaur rocket created a crater about 25 to 30 meters wide, and the LCROSS team estimates that somewhere between 4,000 kilograms (8,818 pounds) to 6,000 kilograms (13,228 pounds) of debris was blown out of the dark crater and into the sunlit LCROSS field of view. The impact created both a low angle and a high angle ejecta cloud. (Read more about the unusual plume in our interview with LCROSS’s Pete Schultz).

The LCROSS team was able to measure a substantial amount of water and found it in several forms. “We measured it in water vapor,” Colaprete said, “and much more importantly in my mind, we measured it in water ice. Ice is really important because it talks about certain levels of concentration.”

With a combination of near-infrared, ultraviolet and visible spectrometers onboard the shepherding spacecraft, LCROSS found about 155 kilograms (342 pounds) of water vapor and water ice were blown out of crater and detected by LCROSS. From that, Colaprete and his team estimate that approximately 5.6 percent of the total mass inside Cabeus crater (plus or minus 2.9 percent) could be attributed to water ice alone.

Colaprete said finding ice in concentrations – “blocks” of ice — is extremely important. “It means there has to be some kind of process by which it is being enhanced, enriched and concentrated so that you have what is called a critical cluster that allows germ formation and crystalline growth and condensation of ice. So that data point is important because now we have to ask that question, how did it become ice?” he said.

In with the water vapor, the LCROSS team also saw two ‘flavors’ of hydroxyl. “We saw one that was emitting as it if it was just being excited,” Colaprete said, “which means this OH could have come from grains — it could be the adsorbed OH we saw in the M Cubed data, as it was released or liberated from a hot impact and coming up into view. We also see an emission from OH that is called prompt emission, which is unique to the emission you get when OH is formed through photolysis.”

Then came the ‘much more.’ Between the LCROSS instruments, the Lunar Reconnaissance Orbiter’s observations – and in particular the LAMP instrument (Lyman Alpha Mapping Project) – the most abundant volatile in terms of total mass was carbon monoxide, then was water, the hydrogen sulfide. Then was carbon dioxide, sulfur dioxide, methane, formaldehyde, perhaps ethylene, ammonia, and even mercury and silver.

“So there’s a variety of different species, and what is interesting is that a number of those species are common to water,” Colaprete said. “So for example the ammonia and methane are at concentrations relative to the total water mass we saw, similar to what you would see in a comet.”

The LCROSS NIR spectrometer field of view (green circle), projected against the target area in the crater Cabeus. Credit: Colaprete, et al.

Colaprete said the fact that they see carbon monoxide as more abundant than water and that hydrogen sulfide exists as a significant fraction of the total water, suggests a considerable amount of processing within the crater itself.

“There is likely chemistry occurring on the grains in the dark crater,” he explained. “That is interesting because how do you get chemistry going on at 40 to 50 degrees Kelvin with no sunlight? What is the energy — is it cosmic rays, solar wind protons working their way in, is it other electrical potentials associated with the dark and light regions? We don’t know. So this is, again, a circumstance where we have some data that doesn’t make entirely a lot of sense, but it does match certain findings elsewhere, meaning it does look cometary in some extent, and does look like what we see in cold grain processes in interstellar space.”

Colaprete said that finding many of these compounds came as a surprise, such as the carbon monoxide, mercury, and particularly methane and molecular hydrogen. “We have a lot of questions because of the appearance of these species, “ he said.

There were also differences in the abundances of all the species over the time – the short 4 minutes of time when they were able to monitor the ejecta cloud before the shepherding spacecraft itself impacted the Moon. “We actually can de-convolve, if you will, the release of the volatiles as a function of time as we look more and more closely at the data,” he said. “And this is important because we can relate what was released at the initial impact, what was released as grains sublimed in sunlight, and what was “sweated out” of the hot crater. So that’s where we’re at right now, it’s not just, ‘hey we saw water, and we saw a significant amount.’ But as a function of time there are different parts coming out, and different ‘flavors’ of water, so we are unraveling it to a finer and finer detail. That is important, since we need to understand more accurately what we actually impacted into. That is really what we are interested in, is what are the conditions we impacted into, and how is the water distributed in the soil in that dark crater.”

So the big question is, how did all these different compounds get there? Cometary impacts seem to offer the best answer, but it could also be outgassing from the early Moon, solar wind delivery, another unknown process, or a combination.

“We don’t understand it at all, really,” Colaprete said. “The analysis and the modeling is really in its infancy. It is just beginning, and now we finally have some data from all these various missions to constrain the models and really allow us to move beyond speculation.”

LCROSS was an “add-on” mission to the LRO launch, and the mission had several unknowns. Colaprete said his biggest fear going into the impact and going into the results was that they wouldn’t get any data. “I had fears that something would happen, there would be no ejecta, no vapor and we’d just disappear into this black hole,” he confessed. “And that would have been unfortunate, even though it would have been a data point and we would have had to figure out how the heck that would happen.”

But they did get data, and in an abundance that — like any successful mission — offers more questions than answers. “It really was exploration,” Colaprete said. “We were going somewhere we had absolutely never gone before, a permanently shadowed crater in the poles of the Moon, so we knew going into this that whatever we got back data-wise would probably leave us scratching our heads.”

Additional source: Science

Posted on by Tega Jessa

Why Can We See the Moon During the Day?

Crescent Moon
Crescent Moon

We all know the basics of the Diurnal Cycle – day and night, sunrise and sunset. And we are all aware that during the day, the Sun is the most luminous object in the sky, to the point that it completely obscures the stars. And at night, the Moon (when it is visible) is the most luminous object, sometimes to the point that it can make gazing at the Milky Way and Deep-Sky Objects more difficult.

This dichotomy of night and day, darkness and light, are why the Moon and the Sun were often worshiped together by ancient cultures. But at times, the Moon is visible even in the daytime. We’ve all seen it, hanging low in the sky, a pale impression against a background of blue? But just what accounts for this? How is it that we can see the brightest object in the night sky when the Sun is still beaming overhead?

Continue reading “Why Can We See the Moon During the Day?”

Posted on by Nancy Atkinson

Flying to the Moon — From the Space Station?

The ISS, from the shuttle mission in May 2010. Credit: NASA

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Last month the International Space Station partner agencies met to discuss the continuation of space station operations into the next decade and its use as a research laboratory. They also did a little forward thinking, and talked about some unique possibilities for the station’s future, including the potential for using the space station as a launching point to fly a manned mission around the Moon. I don’t know what our readers think, but my reactions is: this is just about the coolest idea I’ve heard in a long while! I’m having visions of a Star Trek-like space-dock, only on a smaller scale! In an article by the BBC’s Jonathan Amos, the partners said they want the ISS to become more than just a high-flying platform for doing experiments in microgravity, but also hope to see it become a testbed for the next-generation technologies and techniques needed to go beyond low-Earth orbit to explore destinations such as asteroids and Mars.


“We need the courage of starting a new era,” Europe’s director of human spaceflight, Simonetta Di Pippo, told the BBC News. For sending a mission to the Moon from the ISS, De Pippo said, “The idea is to ascend to the space station the various elements of the mission, and then try to assemble the spacecraft at the ISS, and go from the orbit of the space station to the Moon.”

One “next-generation” activity that is already planned is conducting a flight test of the Variable Specific Impulse Magnetoplasma Rocket (VASIMR) engine on the ISS, which is the new plasma–based space propulsion technology, that could get astronauts to destinations like Mars much quicker than conventional rockets. NASA has sign a commercial Space Act with the Ad Astra company (which is lead by former astronaut Franklin Chang Diaz).

But starting a Moon mission from the ISS is really a far-reaching, kind of “out-there” concept. It would be reminiscent of Apollo 8, and be the first of a new philosophy of using the station as a spaceport, or base-camp from where travelers start their journey. The propulsion system would be built at the station then launched from orbit, just like space travelers have dreamed for decades.

Of course, this is just an idea, and probably an expensive proposition, but isn’t it wonderful that the leaders of the space agencies are even thinking about it, much less talking about it?

Of course, doing zero-g experiments would always be the main focus of the ISS, but just think….

With this type of mission, the future of spaceflight actually be as Canadian astronaut Chris Hadfield describes in the video below. “This is the great stepping off point of to the rest of the universe,” says Hadfield, who will be commanding an upcoming expedition on the ISS. “This is an important moment in the history of human exploration and human capability,… and the space station is a visible sign of the future to come.”

Read more about the idea of an ISS-based Moon mission at BBC.

Posted on by Nancy Atkinson

Moon Balloon Has Mostly Successful Test Flight

ARCA successfully launches the first Romanian space rocket, via balloon. Credit: ARCA

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A Romanian team aiming to send a rocket to the Moon via balloon successfully launched a test flight of their Helen 2 rocket, sending the first Romanian-made rocket system to 40,000 meters above the Earth. The Aeronautics and Cosmonautics Romanian Association (ARCA) team is vying for the Google Lunar X PRIZE, and tested the balloon/rocket system (sometimes called a ‘rockoon’) which launched from a Romanian naval frigate from the Black Sea. While the balloon and rocket worked great, the parachute and recovery system failed. But the team met their main objectives and were ecstatic.

A Romanian naval officer celebrates with a member of the ARCA team after the rocket fired successfully. Credit: ARCA

ARCA has a simple, “green” design. For getting the Moon, a super-huge balloon will carry a system of three rockets to about 18 km (11 miles). Then the first two rocket stages will fire and boost the system into low Earth orbit, and use the final stage to boost it to the Moon. The lander, the European Lunar Explorer (ELE) resembles a knobby rubber ball that uses its own rocket engine to ensure a soft landing. They consider their system to be green, as the rocket engine operates exclusively with hydrogen peroxide

The Helen rocket is lifted into the air by the balloon. Credit: ARCA

The balloon ascent took 40 minutes, bringing the system to an altitude of 14,000 m, at times raising the system at 120 km/h. When it reached that altitude, the flight controllers on the naval ship lit the rocket engines for 30 seconds, bringing it to 40,000 meters. From flight data transmitted to the control centers of ARCA and the Romanian civil aviation authority (ROMATSA) the team was able to confirm the successful flight trajectory, which had an error of only 800 m from the center of their safe trajectory.

A payload on board the capsule took pictures from the top of the trajectory.

An image sent down from the capsule from about 40,000 meters. Credit: ARCA

But at the capsule’s reentry, the parachute did not open, and a ship sent to try and find the capsule in the water was not able to find and retrieve it. But the ARCA team said they didn’t look for it for very long, since most data were transmitted by radio telemetry and satellite and recovery isn’t an objective of the Google Lunar X Prize Competition.

However, they were able to complete the successful launch of the first Romanian space rocket, as well as their first flight of the Google Lunar X Prize Competition. They also verified their rocket stabilization system, and reached the highest altitude ever by an object designed and built entirely in Romania.

In November 2009, ARCA’s test flight hopes were dashed when the balloon’s lines became entangled during inflation and had to be cut, and the test curtailed.

Rockoons were tried and then abandoned by the US in the 1950s because they blew off course in windy conditions.

Watch a video animation of the test flight:

See more images of the test flight at ARCA’s Picasa page.

Source: ARCA

Posted on by Nancy Atkinson

A Rainbow Across the Moon

A 'rainbow' appears on this image from the Lunar Reconnaissance Oribiter

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Even though it is not the mind-blowing experience of a double rainbow all the way across the sky, seeing a rainbow on the Moon is pretty unusual. This curious image from the Lunar Reconnaissance Orbiter shows a rainbow effect across 120 km of the lunar surface. And although water has recently been found on the Moon, water droplets have nothing to do with this rainbow. It comes from illumination conditions and viewing angles with having the Sun directly overhead of the LRO and the Moon.

“This image was acquired as the Sun was exactly overhead, allowing us to observe the ‘opposition surge,’said Brent Denevi, writing on the LRO Camera website. “This is a surge in brightness that occurs when the Sun is directly behind the observer because of two effects. First, there are no shadows seen on the surface, because each boulder and grain of soil’s shadow is hidden directly beneath it. Second, as the light reflects back to the observer it constructively interferes with itself.”

It is a very cool effect, giving the Moon a look having some unexpected color. Denevi said images that contain this type of effect are not just pretty, but useful, too. “They provide a huge new dataset for studying how light interacts with a particulate surface at different wavelengths,” he said. “Perhaps an esoteric-sounding field of study, but this data can help us understand the reflectance images and spectra we have of the Moon and other bodies throughout the Solar System.”

Read more on the LROC website.

Posted on by Nancy Atkinson

China Launches Second Moon Mission

China successfully launched their second robotic mission, Chang’E-2, to the Moon. A Long March 3C rocket blasted off from Xichang launch center just before 1100 GMT on October 1. The satellite is scheduled to reach the Moon in five days, and so far, all the telemetry shows everything to be working as planned. It will take some time for Chang’E-2 to settle into its 100-km (60-mile) orbit above the lunar surfaces, although the China space agency also said the spacecraft will come as close as 15km above the surface during its mission in order to take high-resolution imagery of potential landing sites for Chang’E-3, China’s next lunar mission that will send a rover to the Moon’s surface, scheduled for 2013.
Continue reading “China Launches Second Moon Mission”

Posted on by Nancy Atkinson

The Moon’s South Pole as You’ve Never Seen it Before

LROC Wide Angle Camera (WAC) mosaic of the lunar South Pole region, width ~600 km. Credit: NASA/GSFC/Arizona State University.

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The lunar South Pole – a land of craters, shadows, intrigue and science! This wide-angle mosaic of the South Pole is one of the latest stunning images from the Lunar Reconnaissance Oribiter. The South Pole is the home of Cabeus Crater, where LCROSS impacted in 2009, as well as the Aitken Basin, which contains impact melt that will allow scientists to unambiguously determine the basin’s age, plus Shackleton crater, the region touted as the perfect place for future outposts and huge telescopes. The permanently shadowed regions in this crater wonderland could harbor reservoirs of ice and other volatiles contain a “priceless record of water composition dating back to the beginning of our Solar System, an incomparable dataset for astrobiology investigations,” said Mark Robinson, principal investigator for the Lunar Reconnaissance Orbiter Camera. “Additionally, these volatile deposits could serve as a tremendously valuable resource for future explorers.”

This is one of LROC’s first mosaics of the lunar South Pole, showing the region in all its glory. These mosaics are composed of several individual images taken by the wide-angle camera (WAC) on LRO that are stitched together. These big, beautiful images allow investigators to explore the geophysical and compositional properties of the lunar surface on a global or regional scale.

WAC South Pole mosaic showing locations of major craters. The impact site of the LCROSS spacecraft is marked with an 'X'. Credit: NASA/GSFC/Arizona State University.

All the mosaics from the WAC and the two Narrow Angle Cameras (NAC) and WAC mosaics are produced using a specialized image-processing package called ISIS, the Integrated System for Imagers and Spectrometers. ISIS has the unique capability for processing data from several NASA spacecraft missions and when it applies, scientists can put everything together to get the big picture.

As LRO passes over the pole every two hours, the LROC WAC snaps an image, and over a month, images covering the entire polar region are captured. This mosaic contains 288 images taken in one month; if you look closely, you can see where the month began and ended at about 90°E longitude and note how the lighting changed. This makes the rim of Shackleton crater appear to be slightly disjointed. This is caused by how the Sun came from opposite sides for portions of the mosaic, resulting in opposite sides of the crater’s wall being illuminated in some images. As the mission progresses, the WAC will capture the pole across the full range of seasons and we’ll see even more spectacular views of this region, as well as the entire Moon.

Stay tuned!

Source: LROC website

Posted on by Nancy Atkinson

Astrophysics From the Moon

Lunar New Year

Many astronomers feel that the Moon would be an excellent location for telescopes, — both on the surface and in lunar orbit – and these telescope could help answer some of the most important questions in astronomy and astrophysics today. One proposal calls for a lunar orbiting low frequency antenna that could measure the signatures of the first collapsing structures in the early universe. Dr. Jack Burns from the University of Colorado, Boulder, discussed the idea for the Lunar Cosmology Dipole Explorer (LCODE) at the NASA Lunar Science Institute’s Lunar Forum this summer.

“The Moon in many ways is a truly unique platform from which we can look outward into the cosmos and do some unique astronomical observations,” said Burns, who is also the Director of the NASA/NLSI Lunar University Network for Astrophysics Research (LUNAR).

What makes the Moon so inviting is that the lunar far side is uniquely radio quiet in the inner part of the solar system, as the far side is always facing away from the Earth, and the Moon itself blocks out any interfering man-made signals from radio, TV and satellites.

In this radio quiet zone, astronomers could study the very early universe, back to less than half a billion years after the Big Bang, probing what is called the Dark Ages, before the first stars and galaxies formed.

LCODE would be a satellite orbiting the Moon carrying a single dipole antenna, kind of like your car antenna, Burns said, but it has two ends. “It flies around the Moon and we take data only when we are above the far side, the shielded zone where we are free of radio interference,” said Burns, “and that allows us, because it is so quiet there, to take measurements of these very faint emissions from this very early era in our universe’s history.”

Example of dipole antenna.

The orbiting dipole would allow scientists to look for these signals over the entire sky. If that is successful, the next stage would be to put an array of dipole antennas on the surface, perhaps even about ten thousand antennas, and use it as a radio interferometer that would “allow us to actually get some resolution to do some imaging,” Burns said, “and explore the composition of these structures in the early universe that eventually go on to form stars and galaxies.”

Other proposals for doing radio astronomy from the Moon would be to study the sun at low frequencies, below 10 megahertz. The sun emits very strong low frequency radio waves, and these are related to Coronal Mass Ejections, which produce very high energy particles which can interfere with satellites and could potentially be very harmful to future astronauts traveling in interplanetary space. “We hope to be able to image and to understand how these particles are accelerated,” Burns said.

The other interesting regions of the Moon from which to do astronomy would be the poles in permanently shadowed craters, which are very cold — only about 40 degrees above absolute zero – which would make an excellent site for infrared telescopes which need to be cooled down to very low temperatures.

You can listen to an interview with Jack Burns about LCODE on the 365 Days of Astronomy podcast.