Lunar transit of the International Space Station on Dec. 20,2010. Credit: Theirry Legault. Used by permission.
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From our vantage point on Earth, it takes just a half second for the International Space Station to fly across the face of the Moon, so catching a transit is tricky. But award-winning French astrophotographer Theirry Legault captured an amazingly sharp and detailed transit image that makes the ISS look like it is sitting on the Moon’s surface! Legault took this image from Avranches (Normandy, France) a few hours before the eclipse, on December 20th at 21:34 UT. He used a Meade 10″ ACF on Takahashi EM400, with a Canon 5D mark II. The transit duration was just 0.55 seconds, as the ISS is traveling at 7.5km/s or 28,0000 km/h (17,500 mph). See below for a close-up crop of the image which shows the amount of detail visible of the space station.
Close-up of the ISS transiting the Moon. Credit: Theirry Legault. Used by permission.
Red Moon, Red Mars. Top - Dec 21, 2010 Lunar Eclipse photos of the Red Moon taken near Princeton, NJ on an exquisitely clear night with a 250 mm lens and 1 sec exposure. Credit: Ken Kremer. Bottom Left: Red Mars from the Hubble Space Telescope. Credit: NASA. Right: Red Mars through a telescope in 2010 from The Plantation in Florida (not to scale). Credit: Ernie Rossi
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In this season of Christmas tidings, many of us were blessed to witness the eerie Red Moon of the total lunar eclipse a few nights ago on Dec. 21. Here in “bonechilling” New Jersey, it was miraculously crystal clear the entire night from the beginning around 1:30 a.m. EST to the end – about three and one half hours later at around 5 a.m.
UPDATE: Check out more readers “Red Moon, Red Planet” astropix contributions below !
The eclipse occurred as the moon passed through the Earth’s inner dark shadow, or umbra and changed dramatically to varying shades of red, orange and brown.
Lunar Eclipse 12-21-2010 from The Plantation in Florida. Credit: Ernie RossiDuring totality – when the moon was completely immersed in the umbral shadow for about 72 minutes – the red moon changed from a faint red glow to a brilliant crimson red. At times it appeared to be blood red and as though the surface was stirring and oozing droplets of warm and viscous blood. It was surreal and looked to me as though it had been magically and majestically painted up into the night sky.
Well all this redness hanging in the sky during totality caused me to ponder Mars – the Red Planet – especially with the avalanche of good news streaming back lately.
And the wispy white light at near total eclipse harkened to the Martian polar ice caps.
Mars at Opposition in 2003 from New Jersey. 3.5 in Questar 0.1 seconds. Credit: Robert Vanderbei
Bright red Mars at Opposition in 2003 - The year that Spirit and Opportunity launched.
So please send your telescopic shots and descriptions of the Red Planet and/or the Red Moon and I’ll post them here. Email kremerken at yahoo dot com or post as comments to add here.
Lunar Eclipse from New Jersey 12-21-2010. Credit: Robert Vanderbei
Despite the shadow the moon does not completely disappear. The red moon’s glow was caused by sunlight refracted through the earth’s atmosphere and cast upon the lunar surface. The hue varies depending on a variety of atmospheric conditions and can be intensified by floating clouds of volcanic ash and dust. The recent volcanic eruptions at Mount Merapi in Indonesia in October and at Mount Eyjafjallajökull in Iceland last April sent massive plumes of particles skyward which may have influenced the thrilling event.
Red Moon, Red Planet. One day we’ll journey there and back again.
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Send me your astropix of Red Moon and/or Red Mars to post here:
Check out these gorgeous views of Mars in January 2010 from Efrain Morales Rivera at the Jaicoa Observatory in Aquadilla, Puerto Rico Efrain writes; On this session (01/21/10) on Mars of this years apparition many details could be seen for its size. Image at left at closest to Earth and at the limb (L) Mount Olympus largest volcano in our system, Image at right (01/27/10) closest to the Sun. Credit: Efrain Morales Rivera, Jaicoa Observatory, Aquadilla, Puerto Rico
From Robert Vanderbei of Amateur Astronomers Association Of Princeton in New Jersey; A Lunar Eclipse Montage ! Just ahead of the monster blizzard which struck the northeast Corridor of the US on Dec 26.
Dec. 21, 2010 Lunar Eclipse Montage as imaged from New Jersey. Credit: Robert Vanderbei
Some pictures of the eclipse put together as a composite from beginning to totality by Russell King of Willingboro Astronomical Society, New Jersey.
All pictures were taken with my Canon EOS Digital Rebel XSi from my home in Neptune, New Jersey. I used my Canon 75 to 300MM lens and shot all exposures at 300MM. Camera was set on a fixed photo tripod. The pictures range from 1/2500 second at full moon to 1 second during totality. Images were processed in Photoshop 2 and Ulead. Credit: Russell King. http://www.rddnj.com
The Moon's south pole, as see by the Lunar Reconnaissance Orbier. Credit: NASA/GSFC/Arizona State University.
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No, this is not a wheel of moldy Swiss Cheese. It’s an illumination map of the South Pole of the Moon. There are some areas on the poles of the Moon, particularly the interior of craters, that lie in permanent shadow while other areas remain sunlit for the majority of the year. This image was taken by the Lunar Reconnaissance Orbiter Camera, which has a primary objective of unambiguously identifying these regions. This composite image contains over 1,700 images taken of the same area by the LROC Wide Angle Camera (WAC) over a six month period, which works out to six lunar days.
Here’s how the LROC team described how they created the image:
“Each image was map projected and converted to a binary image (if the ground was illuminated that pixel was set to one, and if shadowed zero) to differentiate between sunlit and shadowed regions. All the binary images were then stacked, and then for each pixel it was determined what percentage of the time during six months that spot was illuminated. Presto – an illumination map! The LROC team is making daily (which is about 28 Earth days) and yearly illumination maps for both poles. Such maps will provide the foundation for planning future robotic and human missions to the poles.”
Sketches made by the Apollo 17 crew of rays created by lofted lunar dust. Credit: NASA
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There are times when Moon appears to have a tenuous atmosphere of moving dust particles that are leaping up from and falling back to the Moon’s surface. First seen during the Surveyor and Apollo eras, these observations were completely unexpected, and scientists today are still trying to understand this phenomenon.
The first indication that something strange was going on with the lunar surface was in the 1960’s when cameras on the Surveyor spacecraft pointing towards the western horizon noticed a brighter hovering cloud that persisted for several hours.
“There are many other bits and pieces of observations of this kind,” said Dr. Mihaly Horanyi from the University of Colorado Boulder’s Laboratory for Atmospheric and Space Physics. “For example, the astronauts in the Apollo command modules that stayed in orbit about the Moon were hoping to take images of the dark sky, but of course there is scattered light from the dust in interplanetary space. But the brightness also appeared to follow the lunar surface, indicating that somehow dust is coming off the surface of the Moon.”
While astronauts from Apollo 8, 10, and 15 all reported such dust clouds, Apollo 17 in 1972 repeatedly saw and sketched what they called “bands,” “streamers” or “twilight rays” for about 10 seconds before lunar sunrise or lunar sunset.
Adding to the mystery, also on Apollo 17 was a dust detector placed on the surface by the astronauts, the Lunar Ejecta and Meteorite experiment, which was supposed to measure the high speed impacts of micrometeorites hitting the moon.
An Apollo 17 astronaut digs in the lunar regolith to study the mechanical behavior of moon dust. Credit: NAS
“Instead the measurements showed an increase of particle fluxes that went up a hundred fold when day turned to night and night turned into day at that location on the Moon,” Horanyi said.
“Every single one of these measurements has an alternate explanation somehow. But it seems that the whole body of these observations is best explained by recognizing that dust — even on an airless body — can move around and come to life.”
Even thought the Moon has no atmosphere, Horanyi said other processes that are likely related to the plasma and radiation environment of the Moon, “the electro-dynamic processes of the near surface lunar environment that can have strong enough electric fields and the surface can have enough electrostatic charges that can break the dust free and somehow shuffle it or move it around the surface.”
In other words, electrostatic charging of the lunar surface causes the dust to levitate, precipitated – somehow – by changes in sunlight.
Horanyi said this type of thing has been seen on other airless bodies, like on Mercury, comets and asteroids.
“For example, the near-landing on the asteroid Eros,”Horanyi said, “people noticed that the bottom of the craters are filled with fine dust, and there is not enough atmosphere, and certainly the body is too small have asteroid shakes – the asteroid version of earthquakes — so the possible transport that would trap or make dust pile up in some regions and move it from others, is most likely a plasma effect.”
Horanyi and other scientists have done lab experiments to try and replicate the lunar environment to see if a dust transport takes place.
“For the first set of experiments, imagine just a piece of surface with dust particles on it, and we shine light on this surface,” he said, “so that half is illuminated, half is not, pretending that there is a terminator region, that the sun is set on one side and is still shining light on the other. When you shine light on the surface with properties that are appropriate, you can emit photo electrons, but you only emit electrons from the lit side, and some of those electrons land on the dark side, — you have a positive charge surplus on the lit and a negative charge pile-up on the night side. Across a couple of millimeters you can easily generate a potential difference of maybe a watt, or a handful of watts, which translates actually as a small-scale, but incredibly strong electric fields. This could be like a kilowatt over a meter. But of course, it only exists over a sharp boundary, and that sharp boundary may be the key to understanding how you get dust moving to begin with.”
Horanyi said in the transient region where boundaries match up – lit and dark boundaries, or boundaries between where the surface is exposed to a plasma and where it is not – those sharp transitions could actually overcome adhesion between dust and the rest of the surface and start moving.
“And that’s where the story gets really interesting,” he said.
Hopefully, a new mission called LADEE (Lunar Atmosphere and Dust Environment Explorer) can help explain this mystery. It is slated to launch in 2013 and fly in low lunar orbit, as close to the surface as 30-50 km. Since NASA may not be sending astronaut to the Moon anytime soon, LADEE’s mission may now be a little different than previously thought, but it still has some important science to conduct.
It will carry three instruments, an infrared imager, a neutral mass spectrometer and a dust detector, which Horanyi is helping to build.
“That hopefully will be capable of measuring tiny, tiny, small particles that people argue are lofted from the surface,” Horanyis said. “And we hope that in combination these instruments might put an end to this argument that we’ve had since the early 1970’s whether dust is really actively transported and shuffled around on the lunar surface or not.”
Seeking to detect mysterious, ultra-high-energy neutrinos from distant regions of space, a team of astronomers used the Moon as part of an innovative telescope system for the search. Their work gave new insight on the possible origin of the elusive subatomic particles and points the way to opening a new view of the Universe in the future.
The team used special-purpose electronic equipment brought to the National Science Foundation’s Very Large Array (VLA) radio telescope, and took advantage of new, more-sensitive radio receivers installed as part of the Expanded VLA (EVLA) project. Prior to their observations, they tested their system by flying a small, specialized transmitter over the VLA in a helium balloon.
In 200 hours of observations, Ted Jaeger of the University of Iowa and the Naval Research Laboratory, and Robert Mutel and Kenneth Gayley of the University of Iowa did not detect any of the ultra-high-energy neutrinos they sought. This lack of detection placed a new limit on the amount of such particles arriving from space, and cast doubt on some theoretical models for how those neutrinos are produced.
Neutrinos are fast-moving subatomic particles with no electrical charge that readily pass unimpeded through ordinary matter. Though plentiful in the Universe, they are notoriously difficult to detect. Experiments to detect neutrinos from the Sun and supernova explosions have used large volumes of material such as water or chlorine to capture the rare interactions of the particles with ordinary matter.
The ultra-high-energy neutrinos the astronomers sought are postulated to be produced by the energetic, black-hole-powered cores of distant galaxies; massive stellar explosions; annihilation of dark matter; cosmic-ray particles interacting with photons of the Cosmic Microwave Background; tears in the fabric of space-time; and collisions of the ultra-high-energy neutrinos with lower-energy neutrinos left over from the Big Bang.
Radio telescopes can’t detect neutrinos, but the scientists pointed sets of VLA antennas around the edge of the Moon in hopes of seeing brief bursts of radio waves emitted when the neutrinos they sought passed through the Moon and interacted with lunar material. Such interactions, they calculated, should send the radio bursts toward Earth. This technique was first used in 1995 and has been used several times since then, with no detections recorded. The latest VLA observations have been the most sensitive yet done.
“Our observations have set a new upper limit — the lowest yet — for the amount of the type of neutrinos we sought,” Mutel said. “This limit eliminates some models that proposed bursts of these neutrinos coming from the halo of the Milky Way Galaxy,” he added. To test other models, the scientists said, will require observations with more sensitivity.
“Some of the techniques we developed for these observations can be adapted to the next generation of radio telescopes and assist in more-sensitive searches later,” Mutel said. “When we develop the ability to detect these particles, we will open a new window for observing the Universe and advancing our understanding of basic astrophysics,” he said.
The scientists reported their work in the December edition of the journal Astroparticle Physics.
NASA’s Cassini Spacecraft is doing some awesome stuff. Stay tuned to NASA’s twitter feed Space Cadets, today should be interesting. I’m Benjamin Higginbotham and this is your SpacePod for November 30th, 2010. Continue reading “Cassini visits Enceladus – SpacePod 2010.11.30”
Many objects in the solar system have strong magnetic fields which deflect the charged particles of the solar wind, creating a bubble known as the magnetosphere. On Earth, this protects us from some of the more harmful solar rays and diverts them to create beautiful aurorae. Similar displays have been found to occur on the gas giants. However, many other objects in our solar system lack the ability to produce these effects, either because they don’t have a strong magnetic field (such as Venus), or an atmosphere with which the charged particles can interact (such as Mercury).
Although the moon lacks both of these, a new study has found that the moon may still produce localized “mini-magnetospheres”. The team responsible for this discovery is an international team composed of astronomers from Sweden, India, Switzerland, and Japan. It is based on observations from the Chandrayaan-1 spacecraft produced and launched by the Indian Space Research Organisation (ISRO).
Using this satellite, the team was mapping the density of backscattered hydrogen atoms that come from solar wind striking the surface and being reflected. Under normal conditions, 16-20% of incoming protons from the solar wind is reflected in this way.
For those excited above 150 electron volts, the team found a region near the Crisium antipode (the region directly opposite the Mare Crisium on the moon). This region was previously discovered to have magnetic anomalies in which the local magnetic field strength reached several hundred nanotesla. The new team found that the result of this was that incoming solar wind was deflected, creating a shielded region some 360 km in diameter surrounded by a “300-km-thick region of enhanced plasma flux that results from the solar wind flowing 23 around the mini-magnetosphere.” Although the flow bunches up, the team finds that the lack of a distinct boundary means that there is not likely to be a bow shock, which would be created as the buildup becomes sufficiently strong to directly interact with additional incoming particles.
Below energies of 100 eV, the phenomenon seems to disappear. The researchers suggest this points to a different formation mechanism. One possibility is that some solar flux breaks through the magnetic barrier and is reflected creating these energies. Another is that, instead of hydrogen nuclei (which composes the majority of the solar wind) this is the product of alpha particles (helium nuclei) or other heavier solar wind ions striking the surface.
Not discussed in the paper is just how valuable such features could be to future astronauts looking to create a base on the moon. While the field is relatively strong for local magnetic fields, it it still around two orders of magnitude weaker than that of Earth’s. Thus, it is unlikely that this effect would be sufficiently strong to protect a base, nor would it provide protection from the x-rays and other dangerous electromagnetic radiation that is provided by an atmosphere.
Instead, this finding poses more in the way of scientific curiosity and can help astronomers map local magnetic fields as well as investigate the solar wind if such mini-magnetospheres are located on other bodies. The authors suggest that similar features be searched for on Mercury and asteroids.
Emily Lakdawalla at the Planetary Society blog unearthed some really cool videos taken by the Chinese Chang’E 2 spacecraft at the Moon. The five engineering videos include Chang’E 2’s solar panel deployment, orbit insertion burn, the first and second orbital trim maneuvers, and low lunar orbit. They are all especially unique in that the video not only includes images from the Moon’s surface, but also the spacecraft itself can be seen, providing a perspective that is not often seen. The video above is of Chang’E 2’s second orbit trim maneuver. Check out Emily’s post to see all five, plus she provides great insights into the video clips, as well.
A self-conscious Moon might ask, “Does my far side look big?” To which lunar scientists would have to reply in the affirmative. They have long known there is a bulge on the Moon’s far side, a thick region of the lunar crust which underlies the farside highlands. But why that bulge is there has been a mystery, and the fact that the far side always faces away from Earth hasn’t helped. Now, a group of international scientists have found that perhaps the tidal processes of Jupiter’s icy moon, Europa, can provide a clue.
“Europa is a completely different satellite from our moon, but it gave us the idea to look at the process of tidal flexing of the crust over a liquid ocean,” said Ian Garrick-Bethell, the lead author of a new paper that offers an explanation for the lop-sided Moon.
Since the Apollo 15 laser altimeter experiment, scientists have known that a region of the lunar far side highlands is the highest place on the Moon. Additionally, the far side has only highlands and no maria.
Like Europa’s icy crust that sits over an ocean of liquid water, the Moon’s crust once floated on a sub-surface ocean of liquid rock. So, could the same gravitational forces from Jupiter that influence Europa also apply to the Earth’s influence on the early Moon?
Garrick-Bethell, from UC Santa Cruz, and his team found that the shape of the Moon’s bulge can be calculated by looking at the variations in tidal heating as the ancient lunar crust was being torn away from the underlying ocean of liquid magma.
Map of crustal thickness. Credit: Garrick-Bethell, et al.
With Europa in mind, the scientists looked at global topography and gravity data sets of the Moon, trying to determine the possibility of how about 4.4 billion years ago, the gravitational pull of the Earth could have caused tidal flexing and heating of the lunar crust. At the polar regions, where the flexing and heating was greatest, the crust became thinner, while the thickest crust would have formed in the regions in line with the Earth.
To back up their theory, they found that a simple mathematical function — a 2-degree spherical harmonics function — can explain the phenomenon. “What’s interesting is that the form of the mathematical function implies that tides had something to do with the formation of that terrain,” said Garrick-Bethell.
The far side of the Moon, photographed by the crew of Apollo 11 as they circled the Moon in 1969. The large impact basin is Crater 308. Credit: NASA
However, this doesn’t explain why the bulge is now found only on the farside of the Moon. “You would expect to see a bulge on both sides, because tides have a symmetrical effect,” Garrick-Bethell said. “It may be that volcanic activity or other geological processes over the past 4.4 billion years have changed the expression of the bulge on the nearside.”
Garrick-Bethell said his team hopes to continue to do more modeling and calculations to fully describe the far side’s features.
“It’s still not completely clear yet, but we’re starting to chip away at the problem,”he said.
The paper will be published in the November 12, 2010 issue of Science.
(Paper not yet available — we’ll post the link when it goes online).
A lunar crater in stunning detail from the Chang'E 2 orbiter. Credit: CNSA / China Lunar Exploration Program
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China’s space agency released the first images taken by the newest lunar orbiter, Chang’E 2. “The relaying back of the pictures shows that the Chang’e-2 mission is a success,” said Zhang Jiahao, director of the lunar exploration center of the China National Space Administration.
During its expected 6-month mission the orbiter will come within 15km above the surface, with the main mission of looking for potential landing for Chang’E-3, China’s next lunar mission that will send a rover to the Moon’s surface, scheduled for 2013. While all the other images are of Sinus Iridum (Bay of Rainbows), a rough translation of the writing on this top image has something to do with “antarctic,” so its possible this could be a crater near one of the lunar poles.
This 3-D map view of the moon’s Bay of Rainbows was taken by China’s Chang’e 2 lunar probe in October 2010. The mission is China’s second robotic mission to explore the moon. Credit: China Lunar Exploration Program
The data for this 3D image was taken by a the spacecraft’s stereo camera from 18.7 km on Oct. 28, four days after launch. The image has a resolution of 1.3 meters per pixel, more than ten times the resolution of pictures from Chang’E 2’s predecessor, Chang’E 1.
For comparison, NASA’s Lunar Reconnaissance Orbiter has a resolution of about 1 meter.
Sinus Iridum is considered to be one of the candidates for the 2013 lander.
Chang’E 2 will also test “soft landing” technology for the lander, which might mean that either the spacecraft is carrying an impactor or that the spacecraft itself will be crashed into the lunar surface like Chang’E 1.
This photo, taken by China’s Chang’e 2 lunar probe in October 2010, shows a crater in the moon’s Bay of Rainbows. . Credit: China Lunar Exploration ProgramAnother Chang'E 2 image. Credit: Credit: China Lunar Exploration Program
