Weekly SkyWatcher’s Forecast: March 5-11, 2012

Open Cluster Messier 50 - Credit: NOAO/AURA/NSF

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Greetings, fellow SkyWatchers! Our week begins with the dance of the planets and a gathering of asteroids. Keep watching as Mars makes its closest approach of the year – while Venus and Jupiter continue to get nearer. Celebrate the Full Worm Moon, interesting stars and beautful galaxies and clusters! Dust off those binoculars and telescopes and meet me in the backyard, because… Here’s what’s up!

Monday, March 5 – Today is the birthday of Gerardus Mercator, famed mapmaker, who started his life in 1512. Mercator’s time was a rough one for astronomy, but despite a prison sentence and the threat of torture and death for his “beliefs,” he went on to design a celestial globe in the year 1551.

Need a little celestial action of your own? Then be outside at twilight with a clear horizon to catch Mercury! joining the show with Venus and Jupiter. The swift inner planet will make a brief appearance on the western skyline just after the Sun dips below the horizon. To add to the fun, the planet Uranus is situated about 5 degrees to its southwest and asteroid Vesta is about 5 degrees south/southwest. More? Then know that asteroid Ceres is also here – just around 20 degrees to Mercury’s southeast. While the asteroids and Uranus really aren’t observable, it’s still fun to know they’re “hanging around” in the same small space!

Tonight we’ll ignore the Moon and use both Sirius and Beta Monocerotis as our guides to have a look at one fantastic galactic cluster for any optical aid – M50 (Right Ascension: 7 : 03.2 – Declination: -08 : 20). Hop about a fistwidth east-southeast of Beta, or northeast of Sirius…and be prepared!

Perhaps discovered as early as 1711 by G. D. Cassini, it was relocated by Messier in 1772 and confirmed by J. E. Bode in 1774. Containing perhaps as many as 200 members, this colorful old cluster resides almost 3000 light-years away. The light of the stars you are looking at tonight left this cluster at a time when iron was first being smelted and used in tools. The Mayan culture was just beginning to develop, while the Hebrews and Phoenicians were creating an alphabet. Do you wonder if it looked the same then as it does now? In binoculars you will see an almost heart-shaped collection of stars, while telescopes will begin to resolve out color and many fainter members – with a very notable red one in its midst. Enjoy this worthy cluster and make a note that you’ve captured another Messier object!

Now, point your telescope towards Mars! This universal date marks the closest approach of Mars and Earth (0.6737 AU = 100.78 million km). While it’s a far cry from being the much celebrated “size of the Moon”, Mars currently has an apparent diameter of 13.89″. This will make for some mighty fine observing, so be sure to check for a lot a great surface details!

Tuesday, March 6 – If you get a chance to see sunshine today, then celebrate the birthday of Joseph Fraunhofer, who was born in 1787. As a German scientist, Fraunhofer was truly a “trailblazer” in terms of modern astronomy. His field? Spectroscopy! After having served his apprenticeship as a lens and mirror maker, Fraunhofer went on to develop scientific instruments, specializing in applied optics. While designing the achromatic objective lens for the telescope, he was watching the spectrum of solar light passing through a thin slit and saw the dark lines which make up the “rainbow bar code.” Fraunhofer knew that some of these lines could be used as a wavelength standard so he began measuring. The most prominent of the lines he labeled with letters that are still in use. His skill in optics, mathematics and physics led Fraunhofer to design and build the very first diffraction grating which was capable of measuring the wavelengths of specific colors and dark lines in the solar spectrum. Did his telescope designs succeed? Of course! His work with the achromatic objective lens is the design still used in modern telescopes!

In 1986, the first of eight consecutive days of flybys began as VEGA 1 and Giotto became the very first spacecraft to reach Halley’s Comet. Tonight let’s just fly by the Moon and have a look at Theta Aurigae. 2.7 magnitude Theta is a four star system ranging in magnitudes from 2.7 to 10.7. The brightest companion – Theta B – is magnitude 7.2 and is separated from the primary by slightly more than 3 arc seconds. Remember that this is what is known as a “disparate double” and look for the two fainter members well away from the primary.

Wednesday, March 7 – Today the only child of William Herschel (the discoverer of Uranus) was born in 1792 – John Herschel. He became the first astronomer to thoroughly survey the southern hemisphere’s sky, and he was discoverer of photographic fixer. Also born on this day, but in 1837, was Henry Draper – the man who made the first photograph of a stellar spectrum.

Tonight the great Grimaldi, found in the central region of the Moon near the terminator is the best lunar feature for binoculars. If you would like to see how well you have mastered your telescopic skills, then let’s start there. About one Grimaldi length south, you’ll see a narrow black ellipse with a bright rim. This is Rocca. Go the same distance again (and a bit east) to spot a small, shallow crater with a dark floor. This is Cruger, and its lava-filled interior is very similar to another study – Billy. Now look between them. Can you see a couple of tiny dark markings? Believe it or not, this is called Mare Aestatis. It’s not even large enough to be considered a medium-sized crater, but is a mare!

Take the time tonight to have a look at Delta Monocerotis with binoculars. Although it is not a difficult double star, it is faint enough to require some optical aid. If you are using a telescope, hop to Epsilon. It’s a lovely yellow and blue system that’s perfect for small apertures.

Thursday, March 8 – On this day in 1977, the NASA airborne occultation observatory made a unique discovery – Uranus had rings!

Tonight we’ll play ring around the Full Moon. In many cultures, it is known as the “Worm Moon.” As ground temperatures begin to warm and produce a thaw in the northern hemisphere, earthworms return and encourage the return of robins. For the Indians of the far north, this was also considered the “Crow Moon.” The return of the black bird signaled the end of winter. Sometimes it has been called the “Crust Moon” because warmer temperatures melt existing snow during the day, leaving it to freeze at night. Perhaps you may have also heard it referred to as the “Sap Moon.” This marks the time of tapping maple trees to make syrup. To early American settlers, it was called the “Lenten Moon” and was considered to be the last full Moon of winter. For those of us in northern climes, let’s hope so!

Friday, March 9 – Today is the anniversary of the Sputnik 9 launch in 1966 which carried a dog named Chernushka (Blackie). Also today we recognize the birth of David Fabricius. Born in 1564, Fabricus was the discoverer of the first variable star – Mira. Tonight let’s visit with an unusual variable star as we look at Beta Canis Majoris – better known as Murzim.

Located about three fingerwidths west-southwest of Sirius, Beta is a member of a group of stars known as quasi-Cepheids – stars which have very short term and small brightness changes. First noted in 1928, Beta changes no more than .03 in magnitude, and its spectral lines will widen in cycles longer than those of its pulsations.

When you’ve had a look at Beta, hop another fingerwidth west-southwest for open cluster NGC 2204 (Right Ascension: 6 : 15.7 – Declination: -18 : 39). Chances are, this small collection of stars was discovered by Caroline Herschel in 1783, but it was added to William’s list. This challenging object is a tough call for even large binoculars and small telescopes, since only around a handful of its dim members can be resolved. To the larger scope, a small round concentration can be seen, making this Herschel study one of the more challenging. While it might not seem like it’s worth the trouble, this is one of the oldest of galactic clusters residing in the halo and has been a study for “blue straggler” stars.

Saturday, March 10 – Since this is a weekend night and we’ve a short time before Moonrise, why not break out the big telescope and do a little galaxy hopping in the region south of Beta Canis Majoris?

Our first mark will be NGC 2207 – a 12.3 magnitude pair of interacting galaxies. Located some 114 million light-years away, this pair is locked in a gravitational tug of war. The larger of the pair is NGC 2207 (Right Ascension: 6 : 16.4 – Declination: -21 : 22), and it is estimated the encounter began with the Milky Way-sized IC 2163 about 40 million years ago. Like the M81 and M82 pair, NGC 2207 will cannibalize the smaller galaxy – yet the true space between the stars is so far apart that actual collisions may never occur. While our eyes may never see as grandly as a photograph, a mid-sized telescope will make out the signature of two galactic cores with intertwining material. Enjoy this great pair!

Now shift further southeast for NGC 2223 (Right Ascension: 6 : 24.6 – Declination: -22 : 50). Slightly fainter and smaller than the previous pair, this round, low surface brightness galaxy shows a slightly brighter nucleus area and a small star caught on its southern edge. While it seems a bit more boring, it did have a supernova event as recently as 1993!

Sunday, March 11 – Tonight let’s return to Canis Major with binoculars and have a look at Omicron 1, the western-most star in the central Omicron pair. While this bright, colorful gathering of stars is not a true cluster, it is certainly an interesting group.

For larger binoculars and telescopes, hop on to Tau northeast of Delta and the open cluster NGC 2362 (Right Ascension: 7: 18.8 – Declination: -24 : 5). At a distance of about 4600 light-years, this rich little cluster contains about 40 members and is one of the youngest of all known star clusters. Many of the stars you can resolve have not even reached main sequence yet! Still gathering themselves together, it is estimated this stellar collection is less than a million years old. Its central star, Tau, is believed to be a true cluster member and one of the most luminous stars known. Put as much magnification on this one as skies will allow – it’s a beauty!

Until next week? Dreams really do come true when you keep on reaching for the stars!

If you enjoy this weekly observing column, then you’d love the fully illustrated The Night Sky Companion 2012. It’s available in both Kindle and soft cover formats!

A ‘Melted’ Moon Makes for Bad Future Landing Sites

Very rough melts show up as red in the mini-RF data (left), but still appear smooth in the corresponding LRO wide angle camera image (right). These impact melts are located just outside Tycho crater, whose rim is visible at the top left. Image Credit Left: Carter et al. Image Credit Right: NASA/GSFC/ASU

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The miniature radio frequency (min-RF) radar instrument aboard the Lunar Reconnaissance Orbiter (LRO) is revealing some interesting things about how impact melts form around craters on the Moon. Impacts produce a crater, ejecta (pulverized rock that is thrown around the crater), and melt. A lot is known about craters and ejecta, because they form such spectacular features on the planetary surfaces. But melt is a fairly minor component of the impact process, and so is not as easily observed. Relatively little is therefore known about impact melts. Now, new data from the mini-RF radar instrument is helping to fill this knowledge gap and also offering insight into future landing spots on the Moon.

Radar is an active remote sensing system, meaning it transmits a signal and then records what bounces back, providing information about the surfaces that were encountered. If the transmitted signal hits a smooth surface, then the returned signal will have a polarization direction that is opposite to what was transmitted. But, if the surface is rough, the signal may bounce more than once, switching polarization each time, so the returned polarization will be the same as the transmitted signals. By controlling the polarization of the transmitted signal and monitoring the polarization of the returned signals, researchers can calculate the ratio of same-sense to opposite sense circular polarization, a parameter called CPR. Smooth surfaces will have a low CPR, while rough surfaces will have a high CPR.

Tycho Melt close up view with LROC data
Pressure ridges can be seen in the rough part of this melt, where the underlying fluid pushed the chilled crust and bunched it up like a table cloth. But even the smooth parts of this melt contain numerous bits of rock, which can't be seen at the scale of this LRO narrow angle camera image.
Image credit: NASA/GSFC/Arizona State University.
Click on the image to explore the LROC data from this area in greater detail.

The mini-RF transmits in the radar S band, at wavelengths of 12.6 cm, and so tells us about surface roughness at the 12.6 cm scale. For example, a sandy beach covered with sand grains that are about 1-2 mm in size (much smaller than the transmitted wavelength) will appear smooth to the Mini-RF (have low CPR values). But, a beach covered with hand-sized pebbles (about the size of the transmitted wavelength) will appear rough (have high CPR values). It is important to note that this kind of information is not currently available from our existing image data, which even at its best can only resolve things on the 50 cm scale. Furthermore, the mini-RF radar can penetrate up to 1 m below the surface, providing information about buried surfaces as well.

Working with the mini-RF data, Dr. Lynn Carter and a team of researchers from NASA Goddard Space Flight Centre, Johns Hopkins University, and the Lunar and Planetary Institute have taken a look at impact melts around a variety of craters. They found that impact melt ponds and flows tend to have CPR values that are greater than surrounding non-melt regions. This means that mini-RF data can be used to help find and identify melt materials, including buried ones! From their limited survey, Dr. Carter and her team have found that impact melt ponds and flows are more common on the Moon than was previously known. With more work, they will be able to better catalogue the number and size of melt ponds and flows around lunar craters, improving our understanding of how much melt is produced by impacts and how it travels.

Dr. Carter and her team also found that, within individual melt ponds or flows, roughness values can vary. Rough surfaces may represent bunching up of a partially cooled crust as it is pushed by the still fluid melt underneath. Such pressure ridges are seen in terrestrial lava flows. Smooth surfaces may represent melts that cooled quickly, or the last melts to arrive at a pond (and so not subject to pushing from more inflowing melt). But, even the “smooth” melts, which appear quite flat in visual imagery, tend to have very high CPR values, indicating that they are, in fact, very rough. There is probably a lot of solid rock and ejecta debris (something we can’t see in the currently available imagery) entrained in the melt material to make them so rough at this scale. To understand what this kind of surface might look like, we can consider terrestrial a’a flows (which are actually slightly less rough than lunar melts).

This work has important implications for future lunar exploration. Imagine how difficult landing on a surface as rugged at an a’a flow would be. This is why site selection scientists work very hard at identifying smooth areas for spacecraft to land. However, if surfaces that look extremely smooth in visual imagery are actually rough like an a’a flow, this can present a problem. Mini-RF data could be helpful in identifying such rough regions and eliminating them from consideration.

Even "smooth" impact melt flows are rougher than this a'a flow, produced by the Kamoamoa fissure eruption in Hawaii. Image Credit: U.S. Department of Interior, U.S. Geological Survey.

Source: Initial observations of lunar impact melts and ejecta flows with the Mini-RF radar, Carter et al., Journal of Geophysical Research V117, 2012, doi:10.1029/2011JE003911.

Is There Life on Earth?

An Earthshine-lit moon sets over ESO's Paranal Observatory in Chile.

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It may seem like a silly question — of course there’s life on Earth — but what if we didn’t know that? What if we were looking at Earth from another vantage point, from another planet in another star system, perhaps? Would we be able to discern then if Earth were in fact teeming with life? All we’d have to go on would be the tiniest bit of light reflected off Earth, nearly lost in the intense glare of the Sun.

Researchers have found that the secret is knowing what kind of light to look for. And they discovered this with a little help from the Moon.

How Earthshine works. (ESO/L. Calçada)

By using Earthshine — sunlight light reflected off Earth onto the Moon — astronomers with the European Southern Observatory have been able to discern variations that correlate with identifying factors of our planet as being a happy home for life.

In observations made with ESO’s Very Large Telescope (VLT), the presence of oceans, clouds, atmospheric gases and even plants could be detected in the reflected Earthshine.

The breakthrough method was the use of spectropolarimetry, which measures polarized light reflected from Earth. Like polarized sunglasses are able to filter out reflected glare to allow you to see clearer, spectropolarimetry can focus on light reflected off a planet, allowing scientists to more clearly identify important biological signatures.

“The light from a distant exoplanet is overwhelmed by the glare of the host star, so it’s very difficult to analyze — a bit like trying to study a grain of dust beside a powerful light bulb,” said Stefano Bagnulo of the Armagh Observatory, Northern Ireland, and co-author of the study. “But the light reflected by a planet is polarized, while the light from the host star is not. So polarimetric techniques help us to pick out the faint reflected light of an exoplanet from the dazzling starlight.”

Since we have fairly reliable proof that life does in fact exist on Earth, this provides astronomers with a process and a benchmark for locating evidence of life on other distant worlds — life as we know it, anyway.

Read more on the ESO website here.

Main image credit: ESO/B. Tafreshi/TWAN (twanight.org). This research was presented in a paper, “Biosignatures as revealed by spectropolarimetry of Earthshine”, by M. Sterzik et al. to appear in the journal Nature on 1st March 2012. The team is composed of Michael F. Sterzik (ESO, Chile), Stefano Bagnulo (Armagh Observatory, Northern Ireland, UK) and Enric Palle (Instituto de Astrofisica de Canarias, Tenerife, Spain).

Face-to-Face With Some Shattered Lunar Boulders

The remains of crumbled boulders in Schiller crater (NASA/GSFC/Arizona State University)

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Breaking up may be hard to do, but these two lunar boulders seem to have succeeded extremely well! Imaged by the Lunar Reconnaissance Orbiter Camera (LROC) in October of 2009, this crumbled couple was recently identified by Moon Zoo team member Dr. Anthony Cook and brought to the attention of the project’s forum moderator.

The tracks left in the regolith — lunar soil — behind the boulders tell of their past rolling journeys down the slope of the elongated Schiller crater, in which they reside. Rolling boulders have been spotted before on the Moon, but what made these two split apart? And…why does that one on the lower right look so much like half a face?

Several things can cause lunar boulders to come loose and take the nearest downhill course. Meteorite impacts can shake the ground locally, giving the rocks enough of a nudge to set them on a roll. And moonquakes — the lunar version of earthquakes, as the name implies (although not due to tectonic plate shifts but rather to more mysterious internal lunar forces) — can also dislodge large boulders.

The low gravity on the Moon can make large rocks take a bounding path, evidenced by the dotted-line appearance of some of the trails.

Could all that bounding and bouncing have made the two boulders above shatter apart? Or was something else the cause of their crumbling?

Dr. Cook suggested that the boulders could have fractured before they began rolling, and then the added stress of their trip down the crater’s slope (uphill is to the right) made them break apart at the end of their trip… possibly due to further weathering and the extreme temperature variations of lunar days and nights.

Although a sound idea, Dr. Cook added, “I’m a bit puzzled though why the one on the top left has rock debris so far away from the centre. The boulder that looks like a skull rock on the bottom right has debris a lot closer to it, that could simply be explained by bits falling off as one would expect from the explanation above.”

This is one rock that's not happy about its breakup!

Another idea is that the boulders were struck by meteorites, but it seems extremely improbable that two would have been hit right next to each other. Still, not impossible, especially given the geologic time spans in play.

And as far as the “skull rock” boulder is concerned… that’s a little something called pareidolia, the tendency for our brains to interpret random shapes as something particularly significant. In this case it’s a human face, one of the most popular forms of pareidolia (perhaps best known by the famous “Face on Mars”, which, as we all now know, has been since shown to be just another Martian mesa.)

It does look like a face though, and not a particularly happy one!

Find out more about rolling boulders and Schiller crater on the LROC site hosted by Arizona State University here, and take a look at the full image scan of the region yourself… you may find more of these broken-up rolling rocks!

LROC WAC global 100-meter mosaic image of the 180-km long, 70-km wide Schiller crater. Overlaid onto a laser altimetry elevation model. (NASA/GSFC/Arizona State University)

A Weekend Sky Show: Moon, Venus and Jupiter

Moon and Venus on Feb. 25, 2012. © Jason Major

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As promised by Nancy in a previous article on Universe Today, Venus was visible during the daylight hours this Saturday, very close to the crescent Moon. If you had clear weather you may have been able to catch a glimpse of the scene above, photographed from my location in north Texas at 6:35 p.m. local time.

Dim but visible, Venus is the “star” at lower left.

Later that same evening the show really went into full force as the Moon was illuminated by Earthshine in the western sky, with Venus ablaze and Jupiter making a bright appearance as well!

Nancy wrote on Feb. 24: If you don’t see Venus during the day, try to see Venus immediately at sunset; and right now, the Moon, Venus and Jupiter are lining up for triple conjunction at dusk, and with clear skies, it will be a great view that is almost impossible to miss!

A great view indeed! I grabbed a quick shot with my iPhone camera of the conjunction, and took the opportunity to point out the view to some neighbors as well.

Conjunction of the Moon, Venus and Jupiter on Feb. 25, 2012. (Jason Major)

One of the more dramatic planetary conjunctions I’ve seen, especially with the light from a fading sunset illuminating the stage.

Sometimes the best astronomy is the type you can see with your own eyes… and be able to easily share with others!

ADDED 2/26: Sunday evening brought some great views as well! Here’s a photo from around 6:45 pm on Feb. 26th:

Jupiter, the Moon and Venus on Feb. 26, 2012. © Jason Major

 

If the Moon Currently has Liquid Magma, Why isn’t it Erupting?

A new look at old data has given scientists more insight into the Moon's core. Credit: Science

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Last year, scientists took another look at the seismic data collected by Apollo era experiments and discovered that the lower mantle of the Moon, the part near the core-mantle boundary, is partially molten (e.g., Apollo Data Retooled to Provide Precise Readings on Moon’s Core, Universe Today, Jan. 6, 2011). Their findings suggest that the lowest 150 km of the mantle contains anywhere from 5 to 30% liquid melt. On the Earth, this would be enough melt for it to separate from the solid, rise up, and erupt at the surface. We know that the Moon had volcanism in the past. So, why is this lunar melt not erupting at the surface today? New experimental studies on simulated lunar samples may provide the answers.

It is suspected that the current lunar magmas are too dense, in comparison to their surrounding rocks, to rise to the surface.  Just like oil on water, less dense magmas are buoyant and will percolate up above the solid rock. But, if the magma is too dense, it will stay where it is, or even sink.

Motivated by this possibility, an international team of scientists, led by Mirjam van Kan Parker from the VU University Amsterdam, has been studying the character of lunar magmas. Their findings, which were recently published in the Journal Nature Geoscience, show that lunar magmas have a range of densities that are dependent on their composition.

Ms van Kan Parker and her team squeezed and heated molten samples of magma and then used X-ray absorption techniques to determine the material’s density at a range of pressures and temperatures. Their studies used simulated lunar materials, since lunar samples are considered too valuable for such destructive analysis. Their simulants modelled the composition of Apollo 15 green volcanic glasses (which have a titanium content of 0.23 weight %) and Apollo 14 black volcanic glasses (which have a titanium content of 16.4 weight %).

Samples of these simulants were subjected to pressures up to 1.7 GPa (atmospheric pressure, at the surface of the Earth, is 101 kPa, or 20,000 times less than what was achieved in these experiments). However, pressures in the lunar interior are even greater, exceeding 4.5 GPa. So, computer calculations were conducted to extrapolate from the experimental results.

Apollo 15 green glass beads
Apollo 15 green glass beads. Credit: NASA

The combined work shows that, at the temperatures and pressures typically found in the lower lunar mantle, magmas with low titanium contents (Apollo 15 green glasses) have densities that are less than the surrounding solid material. This means they are buoyant, should rise to the surface, and erupt. On the other hand, magmas with high titanium contents (Apollo 14 black glasses) were found to have densities that are about equal to or greater than their surrounding solid material. These would not be expected to rise and erupt.

Since the Moon has no active volcanic activity, the melt currently located at the bottom of the lunar mantle must have a high density. And, Ms van Kan Parker’s results suggest that this melt should be made of high titanium magmas, like those that formed the Apollo 14 black glasses.

A new look at old data has given scientists more insight into the Moon's core. Credit: Science

This finding is significant, because high titanium magmas are thought to have formed from titanium-rich source rocks. These rocks represent the dregs that were left at the base of the lunar crust, after all the buoyant plagioclase minerals (which make up the crust) had been squeezed upwards in a global magma ocean. Being dense, these titanium-rich rocks would have quickly sunk to the core-mantle boundary in an overturn event. Such an overturn even had been postulated over 15 years ago. Now, these exciting new results provide experimental support for this model.

These dense, titanium-rich rocks are also expected to have a lot of radioactive elements, which tend to get left behind when other elements are preferentially taken up by mineral crystals. The resulting radiogenic heat from the decay of these elements could explain why parts of the lower lunar mantle are still hot enough to be molten. Ms van Kan Parker and her team further speculate that this radiogenic heat could also be helping to keep the lunar core partially melted even today!

Sources:
X-Rays Illuminate the Interior of the Moon, Science Daily, Feb. 19, 2012.
Neutral buoyancy of titanium-rich melts in the deep lunar interior, van Kan Parker et al. Nature Geoscience, Feb. 19, 2012, doi:10.1038/NGEO1402.

A Mardi Gras Moon Crossing

SDO AIA image of the Sun and Moon at 14:11 UT on Feb. 21, 2012

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The Sun seems to be glowing in traditional Mardi Gras colors in this image, made from three AIA channels taken today at approximately 14:11 UT (about 9:11 a.m. EST) as the Moon passed between it and the Solar Dynamics Observatory spacecraft. Looks like it’s that time of year again!

During portions of the year, the Moon transits the Sun on a regular basis from the perspective of NASA’s SDO spacecraft, which lies within the Moon’s orbit. When this happens we are treated to an improvised eclipse… and it gives SDO engineers a way to fine-tune the observatory’s calibration as well.

Here are more AIA views of the same event captured in different wavelengths:

Lunar transit on 2-21-12; AIA 304
Lunar transit on 2-21-12; AIA 193
Lunar transit on 2-21-12; AIA 4500

…and here’s an interesting image taken in HMI Dopplergram:

HMI Dopplergram image of transit

While the AIA (Atmospheric Imaging Assembly) images the Sun in light sensitive to different layers of its atmosphere, the Helioseismic and Magnetic Imager (HMI) studies oscillations in the Sun’s magnetic field at the surface layer.

Watch a video of the path of this lunar transit, posted by the SDO team here.

And if you happen to be reading this as of the time of this writing (appx. 10:06 a.m. EST) you can keep up with the latest images coming in on the SDO site at http://sdo.gsfc.nasa.gov/.

It’s Mardi Gras and the Moon doesn’t want to miss out on any of the fun!

Images courtesy of NASA/SDO and the AIA, EVE, and HMI science teams. Hat-tip to Mr. Stu Atkinson who called the AIA alert on Twitter.

Get Your Own Unprecedented 3-D View of the Moon

This AIPP image is a 1000-by-666-pixel section of the full-resolution 3-D map that Jeffrey Ambrozia will create, which will be a 5398-by-7000-pixel graphic. This shows Heinsius crater. Image courtesy Jeffrey Ambroziak.

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Love 3-D images? Interested in maps? Want to explore the Moon? Then a new Kickstarter project may be just what you are looking for. Jeffrey Ambroziak, creator of a specialized 3-D map projection method, will be producing what he calls the first true 3-D map of the Moon, and he is offering space enthusiasts the chance to get either digital or paper copies of the map, created from recently released data from the Lunar Reconnaissance Orbiter. Interest in the project has skyrocketed, and while the goal of $5,000 has already been reached by more than double that amount, Ambroziak is now thinking of what more he can offer to backers of his PopView 3D Moon Map.

“We’re at a place now where you can do some interesting research on your own, and it doesn’t necessarily require a large institution,” Ambroziak said by phone. “I love the idea of using Kickstarter to give interested and passionate space aficionados the opportunity to work with us.”

The maps will include not only 3-D views of the Moon’s surface, but on the “front side” will be “National Geographic-style” graphics and information.

Ambroziak said the backers who fund his project will be instrumental choosing the mapping locations and the information that is included.

“This will be very a very collaborative effort to pick the things we will put on the front of the map and the areas that we actually map in 3-D,” he told Universe Today. “As the Kickstarter project description makes clear, we are going to leverage the knowledge of all involved to produce a map that is as informative as it is innovative while letting everyone experience our excitement as the project takes shape. And in the end, everyone gets a copy of the map!”

Ambroziak added, “In the current age with NASA’s budget cuts and the space agency looking towards private enterprise more, there is now a place for interested people to create very interesting and useful space products. We spend billions of dollars to gather incredibly beautiful data of the Moon and Mars and much of it just sits around. We are looking to do our part to bring this data to life, and I’m proof of that you don’t have to sit around and wait for NASA to make an image from LROC data. We don’t have to wait anymore, we can do it ourselves.”

Ambroziak has been overwhelmed that his project is so popular. “I love the idea of the feedback that I’m getting already from people who are so excited about this project,” he said. Most gratifying was a top level pledge of $1,200 from former astronaut and shuttle pilot William Readdy, pledged $1200 to the project who wished Ambroziak “godspeed” in the effort. “It’s pretty neat when astronauts see the importance of what is being attempted,” Ambroziak said.

His patented Ambroziak Infinite Perspective Projection (AIPP) is a map projection method used for three-dimensional stereo visualization of geographic data, which allows viewers to see precise representation of data in 3-D, no matter what angle or distance the image is being viewed. He detailed the method in his book, Infinite Perspectives: Two Thousand Years of Three-Dimensional Mapmaking, (Princeton Architectural Press, 1999) and has previously created 3-D maps of Antarctica and Mars, which have been displayed at museums such as the Peabody Museum of Natural History.

I asked Ambroziak how far along he was with the project.

“I have downloaded all of the LROC imagery and digital elevation information,” he said. “I have further processed the image data to stretch out the contrast, computed shadows from the digital elevation model, and mixed the computed shadows back into the imagery to improve appearances. AIPP is then applied as desired to create 3D images. Specifically, imagery and digital elevation data is combined in accordance with a few chosen AIPP parameters (vertical exaggeration, view plane elevation, etc.) to produce the AIPP map.”

But that is only the technical part of the project, as the “front side” of the maps will be more artistic.

“I will be able to poll the backers for their preferred area of interest,” he said. “In short, you back the project, you have a say in the mapping of the Moon! Ultimately, I would like to perform a systematic mapping of the entire surface of the Moon in accordance with the USGS quad-map nomenclature and format. This is just the first step. This is Kickstarter – not start and then end.”

Check out the Kickstarter page for the “prizes” or incentives are for the various levels of funding. They range from getting a digital copy emailed to you, to complete posters, to an invitation to dinner for you and a guest with the Ambroziak, with food and drinks on him.

Lunar Crater Reveals Many Secrets, Including a Not-So-Young Age

Giordano Bruno crater on the Moon
Giordano Bruno crater on the eastern far side limb of the Moon (35.9? N, 102.8? E) is being revealed in great detail by the Lunar Reconnaissance Orbiter Camera.

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The Moon is covered with craters of various shapes and sizes, and in various states of preservation. Scientists have studied these spectacular features for over five decades, yet there are still many things about craters that we just don’t understand. The study of craters is important because we use them to determine the ages of planetary surfaces. Now, very high resolution imagery from the Lunar Reconnaissance Orbiter Camera (LROC) is allowing us to see lunar craters as never before. Under such scrutiny, one very fresh crater is revealing a host of secrets about the crater-forming process and revealing that it’s not as young as some people may have originally thought.

The crater in question is Giordano Bruno, a 22 km diameter crater located on the far side of the Moon, just beyond the eastern limb. Like all craters on the Moon, this one was named after a famous scientist, in this case, a sixteenth century Italian philosopher who was burned at the stake in 1600 for proposing the existence of “countless Earths.” Because of its position on the far side, Giordano Bruno crater was not seen by humans until it was photographed by the Soviet Luna-3 mission in 1959. But then, this crater was immediately recognized as one of significance, because of its very bright and extensive ray system.

Moon Eastern Limb Clementine
The spectacular rays and the brightness of Giordano Bruno crater are evident in this Clementine data mosaic of the eastern limb of the Moon. Giordano Bruno is the bright spot in the upper centre of this image and some of its rays can be seen extending a quarter of the way around the lunar globe.
Image credit: NASA/JPL/USGS

Along with its bright rays, the crisp rim of the crater, it’s very steep slopes, and a lack of observed superposed craters all argued for a very young age for this intriguing crater. Some researchers even suggested that the formation of this crater was observed by medieval monks in 1178, and recorded as a lunar transient event. Other workers think the age should be closer to 1 million years old. This is still very young by the standards of similar-sized lunar craters, but not within written history.

Over the past 2 years, the acquisition of LROC data has allowed Giordano Bruno crater to be studied in much greater detail than ever before. Images taken by the LROC Narrow Angle Cameras (NAC’s) have resolutions of about half a meter per pixel. This means that something the size of a chair would take up one pixel, and your kitchen table would be roughly resolvable as a 2 x 3 pixel rectangle. With resolutions like that, interesting and unexpected features are being revealed.

One of the most spectacular features is a swirl of impact melt on the western edge of the crater floor. This whirlpool-like structure shows that the melt here underwent chaotic mixing while it was liquid. You can also see that parts of the melt are actually mixtures of real melt and rock fragments that have been incorporated during movement of the melt.

Melt Swirl in Giordano Bruno crater, Moon
Like cream in coffee, a swirl captures the incomplete mixing that occurred when a viscous combination of impact melt and rock fragments flowed off the crater walls into some less rocky impact melt, which had pooled at the western edge of the crater.
Image credit: NASA/GSFC/Arizona State University

Recently published work by Dr. Yuriy Shkuratov (from the Astronomical Institute of Kharkov in Ukraine) and his colleagues used a new technique to study this swirl. Multiple images taken under different conditions were combined to provide roughness calculations for the area. Their research shows that there is a depression in the centre of this structure and that higher segments of the whirlpool swirl exhibit greater roughness than the surrounding melt. They interpret this to mean that the cooling impact melt pool was disturbed by melt flows coming off the crater walls. These incoming flows were more viscous because they had incorporated rock fragments and so did not mix as readily with the other melt material.

One of the other features studied by Dr. Shkuratov and his team is a large slump of wall material near the northern rim of Giordano Bruno. Such slumps are common in larger craters and are believed to form during the late stages of crater formation. This means that the slump block should be the same age as the crater. However, Dr. Shkuratov and colleagues have found that, while there are no craters on the slumped material, a number of small craters are located on the inner wall near this large landslide. They interpret this to mean that the slump is a more recent event. This is significant, because up until now, such big changes were not thought to occur so long after crater formation.

Slump Block in Giordano Bruno crater, Moon
A segment of the crater wall detaches and slumps downward. But when?
Image credit: NASA/GSFC/Arizona State University

The most intriguing result of Dr. Shkuratov’s study is the indication of a not-so-young age for Giordano Bruno. A number of very bright landslides, much smaller than the one on the north wall, are observed around the crater. Similarly, small bright craters are found superposed on many parts of the crater walls. These landslides and craters are much brighter than the surrounding materials. On the Moon, brighter means younger, since materials tend to darken as they age, due to a process called “space weathering.” If these craters and landslides are indeed young, this means that the surrounding darker material of Giordano Bruno crater must be older. Data from Japan’s Kaguya mission confirms that these variations in brightness are not related to compositional variations, and so must be age-related. Based on this and other evidence, Dr. Shkuratov’s team conclude that Giordano Bruno crater must be at least one million years old.

So, whatever the medieval monks saw when they recorded the occurrence of a lunar transient event in 1178, it was not the impact that formed Giordano Bruno crater.

Discover the secrets of Giordano Bruno crater for yourself, using LROC data at the ACT-REACT Quick Map web site

Source: The lunar crater Giordano Bruno as seen with optical roughness imagery. Shkuratov et al., Icarus 218, 2012, 525-533, doi:10.1016/j.icarus/2011.12.023.

China Unveils High Resolution Global Moon Map

China Publishes High Resolution Full Moon map from Chang'e-2 Lunar Orbiter. Chinese scientists assembled a full moon map using images captured by the Chang’e-2 spacecraft with an an unprecedented resolution of 7-meters. Credit: China Space Program

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Chinese scientists have assembled the highest resolution map ever created of the entire Moon and unveiled a series of global Moon images on Monday, Feb. 6.

The composite Lunar maps were created from over 700 individual images captured by China’s Chang’e-2 spacecraft and released by the country’s State Administration of Science, Technology and Industry for National Defence (SASTIND), according to reports from the state run Xinhua and CCTV new agencies.

“The map and images are the highest-resolution photos of the entirety of the Moon’s surface to be published thus far,” said Liu Dongkui, deputy chief commander of China’s lunar probe project, reports Xinhua.

Of course there are much higher resolution photos of numerous individual locations on the Moon taken from orbit by the spacecraft of other countries and from the surface by NASA’s Apollo lunar landing astronauts as well as unmanned Russian & American lunar landers and rovers.

China unveils High Resolution Global Moon map from Chang'e-2 Lunar Orbiter
Credit: China Space Program

Chang’e-2 is China’s second lunar probe and achieved orbit around our nearest neighbor in space in October 2010. It was launched on Oct. 1, 2010 and is named after a legendary Chinese moon goddess.

The images were snapped between October 2010 and May 2011 using a charge-coupled device (CCD) stereo camera as the spacecraft flew overhead in a highly elliptical orbit ranging from 15 km to 100 km altitude.

The Chang’e-2 maps have a resolution of 7 meters, which is 17 times greater than from China’s first lunar orbiter; Chang’e-1, launched in 2007.

Global Lunar Map from China’s Chang'e-2 Lunar Orbiter. Credit: China Space Program

In fact the maps are detailed enough that Chinese scientists were able to detect traces of the Apollo landers, said Yan Jun, chief application scientist for China’s lunar exploration project.


Chang’e-2 also captured high resolution photos of the “Sinus Iridum”area , or Bay of Rainbows, where China may land their next Moon mission. The camera had the ability to resolve features as small as 1 meter across at the lowest altitude.

The satellite left lunar orbit in June 2011 and is currently orbiting the moon’s second Lagrange Point (L2), located more than 1.5 million km away from Earth.

Chinese space program officials hope for a 2013 liftoff of the Chang’e-3 lunar rover, on what would be China’s first ever landing on another celestial body. China’s next step beyond the rover may be to attempt a lunar sample return mission in 2017.

Demonstrating the ability to successfully conduct an unmanned lunar landing is a key milestone that must be achieved before China can land astronauts on the Moon, perhaps within the next decade.

NASA’s twin GRAIL spacecraft recently achieved Lunar orbit over the New Year’s weekend. The duo of probes were just renamed as “Ebb and Flow” – the winning entries in an essay naming contest submitted by 4th Grade US students from Bozeman, Montana.

At this time NASA does not have the funding or an approved robotic lunar landing mission, due to severe budget cuts.And even worse NASA cuts will be announced shortly !

Russia hopes to send the Lunar Glob spacecraft to land on the Moon around 2015.

Since the United States has unilaterally scuttled its plans to return American astronauts to the Moon’s surface, it’s very possible that the next flag planted on the Moon by humans will be Chinese.