Space and astronomy news
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We’re conducting a completely informal, unscientific, off-the-cuff survey of Universe Today readers. When do you think that humans will return to the Moon?
Just give us your responses in the comments. We’re thinking of pulling your answers together to try and wrangle the zeitgeist about human space exploration.
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With blastoff just 2 ½ weeks away, NASA’s GRAIL lunar twins completed a major milestone towards launch today (Aug. 18) when they were mated to the top of the Delta II Heavy rocket that will boost them to the moon. Launch is slated for Sept. 8 at 8:37 a.m. EDT.
This morning the tightly wrapped $496 Million duo took their last trip on Earth before beginning their nearly four month journey to the Moon. GRAIL A & GRAIL B were carefully transported 15 miles (25 km) from the clean room processing facility at the Astrotech Space Operation’s payload processing facility in Titusville, Fla to Space Launch Complex 17B (SLC-17B) at Cape Canaveral Air Force Station in Florida.
“The GRAIL spacecraft transportation convoy to SLC-17B departed Astrotech at 11:55 p.m. EDT on Wednesday, Aug. 17, “ said Tim Dunn, NASA’s Delta II Launch Director in an interview with Universe Today. “The spacecraft, inside the handling can, arrived at the launch pad, SLC-17B, at 4:00 a.m. this morning.”
“The spacecraft was then hoisted by the Mobile Service Tower crane onto the Delta II launch vehicle and the spacecraft mate was complete at 9:30 a.m.”
Technicians joined the nearly identical and side by side mounted spacecraft onto the top of the guidance section adapter of the Delta’s second stage. The Delta II was built by United Launch Alliance (ULA).
“Tomorrow, the GRAIL spacecraft team will perform functional testing on both the GRAIL A and GRAIL B spacecraft,” Dunn told me.
“The next major milestone will be performance of the Integrated Systems Test (IST) on Monday, (8/22/11).
“Today’s spacecraft mate operation was flawlessly executed by the combined ULA and NASA Delta II Team,” said Dunn.
These tests will confirm that the spacecraft is healthy after the fueling and transport operations. After further reviews of the rocket and spacecraft systems the GRAIL team will install the payload fairing around the lunar probes.
NASA’s dynamic duo will orbit the moon to determine the structure of the lunar interior from crust to core and to advance understanding of the thermal evolution of the moon.
“We are about to finish one chapter in the GRAIL story and open another,” said Maria Zuber, GRAIL’s principal investigator, based at the Massachusetts Institute of Technology in Cambridge in a statement. “Let me assure you this one is a real page-turner. GRAIL will rewrite the book on the formation of the moon and the beginning of us.”
The GRAIL launch will be the last for a Delta II in Florida.
Read my prior features about GRAIL
GRAIL Twins ready for NASA Science Expedition to the Moon: Photo Gallery
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We thought we knew everything there was to know about our Moon, but new investigations into its volcanic origins are causing scientists to take another look at how our nearest astronomical neighbor formed – and its age. If you like a little lunacy in your life, then step inside and read more…
A team of scientists led by Carnegie’s Erik Hauri have been busy studying seven tiny Apollo 17 return samples with a a state-of-the-art NanoSIMS 50L ion microprobe. These little pieces of lunar “evidence” are fragments of lunar magma which contain crystals called “melt inclusions”. High in titanium content, these crystals were once a part of volcanic glass beads ejected in explosive volcanic eruptions. The cool part is these melt inclusions coughed up from the lunar depths eons ago yielded a discovery – the magma trapped within crystals show a hundred times more water than once believed.
“In contrast to most volcanic deposits, the melt inclusions are encased in crystals that prevent the escape of water and other volatiles during eruption. These samples provide the best window we have to the amount of water in the interior of the Moon,” said James Van Orman of Case Western Reserve University, a member of the science team. The paper’s authors are Hauri; Thomas Weinreich, Alberto Saal and Malcolm Rutherford from Brown University; and Van Orman.
As meteorite fans well know, water content is everything and the inner Solar System was nearly devoid of it and other volatile elements during early formation. Past lunar studies show an even lower content, supporting the giant impactor theory – a theory which could very well need to be reconsidered. New findings also point to the need for more sample returns from other Solar System bodies as well.
“Water plays a critical role in determining the tectonic behavior of planetary surfaces, the melting point of planetary interiors, and the location and eruptive style of planetary volcanoes,” said Hauri, a geochemist with Carnegie’s Department of Terrestrial Magnetism (DTM). “We can conceive of no sample type that would be more important to return to Earth than these volcanic glass samples ejected by explosive volcanism, which have been mapped not only on the Moon but throughout the inner Solar System.”
But this isn’t a first for Saal. Three years ago the same team reported the first evidence for the presence of water in lunar volcanic glasses. Using modeling, they were able to theorize how much water was contained within the magma before eruption. From those results, Weinreich, a Brown University undergraduate, found the melt inclusions. This permitted the team to measure the pre-eruption concentration of water in the magma and estimate the amount of water in the Moon’s interior.
“The bottom line,” said Saal, “is that in 2008, we said the primitive water content in the lunar magmas should be similar to the water content in lavas coming from the Earth’s depleted upper mantle. Now, we have proven that is indeed the case.”
Of course, this could mean changing scientific thought on where lunar pole ice deposits originated, too. Current theory suggests they are the product of comets and meteoroid impacts – but perhaps they also could be magma related. It’s a fascinating study which could also help us to understand the properties of other planetary bodies.
But the magma doesn’t stop there…
According to new research from a team that includes Carnegie’s Richard Carlson and former-Carnegie fellow Maud Boyet, magma samples might be revealing a younger Moon, too. Building on the giant impactor theory, samples of a rock type called ferroan anorthosite, or FAN, are being examined. Believed to be the oldest of the Moon’s crustal rocks, FAN could be as old as 4.36 billion years – a figure much younger than previous lunar estimates. Using isotopes of the elements lead and neodymium, the team analyzed the samples for consistent ages from multiple isotope dating techniques.
“The extraordinarily young age of this lunar sample either means that the Moon solidified significantly later than previous estimates, or that we need to change our entire understanding of the Moon’s geochemical history,” Carlson said.
What does all this mean? Thanks to our understanding of the oldest terrestrial minerals, such as zircons from western Australia, we can derive the Moon’s crust may have evolved at the same time as Earth’s… a time which could date back to a giant impact. “The Earth’s Moon is the archetypical example of this type of differentiation.” says the team. “Evidence for a lunar magma ocean is derived largely from the widespread distribution, compositional and mineralogical characteristics, and ancient ages inferred for the ferroan anorthosite (FAN) suite of lunar crustal rocks.”
The next time you observe the Moon, remember… she’s a bit younger than you thought!
Original News Source: Carnegie Science News and Science Daily.
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NASA’s GRAIL twins – dubbed GRAIL-A & GRAIL-B – are ready to embark on America’s next science expedition to the moon in less than 1 month’s time from Cape Canaveral Air Force Station, Fla.
The twin Gravity Recovery and Interior Laboratory (GRAIL) spacecraft have been exhaustively tested, fueled for flight and mounted side-by-side on a specially designed payload adapter inside the controlled environment of a clean room at the Astrotech Space Operations facility in nearby Titusville, Fla.
The next processing step is to encapsulate the lunar probes inside their protective payload fairing. The duo are set to be shipped from Astrotech to their Cape Canaveral launch pad next week on Aug. 16, where they will be mated to an already assembled Delta II booster.
Liftoff of the GRAIL twins is slated for Sept. 8 at 8:37 a.m. EDT by a Delta II Heavy rocket from Launch Complex 17 at Cape Canaveral for a nearly four month voyage to the moon.
After entering lunar orbit, the two GRAIL spacecraft will fly in a tandam formation just 50 kilometers above the lunar surface with an average separation of 200 km during the 90 day science phase.
GRAIL’s mission goal is to map the moon’s gravity field to high precision and thereby deduce the structure of the lunar interior from crust to core. This will also lead to a better understanding of the composition of the moon’s interior, according to Sami Asmar, GRAIL co-investigator from NASA’s Jet Propulsion Laboratory in Pasasdena, Calif., during an interview inside the Astrotech clean room at a photo opportunity for the media. A gravity experiment is also aboard the just launched Jupiter bound Juno spacecraft.
GRAIL Photo Album special taken from inside the Astrotech cleanroom facility.
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Every year from late July to mid-August, the Earth encounters a trail of debris left behind from the tail of a comet named Swift-Tuttle. This isn’t the only trail of debris the Earth encounters throughout the year, but it might be one of the most notorious as it is responsible for the annual Perseid meteor shower, one of the best and well-known yearly meteor showers.
Comet Swift-Tuttle is a very long way away from us right now, but when it last visited this part of the Solar system, it left behind a stream of debris made up of particles of dust and rock from the comet’s tail.
Earth encounters this debris field for a few weeks, reaching the densest part on the 11th to 13th August.
The tiny specs of dust and rock collide with the Earth’s atmosphere, entering at speeds ranging from 11 km/sec (25,000 mph), to 72 km/sec (160,000 mph). They are instantly vaporised, emitting bright streaks of light. These tiny particles are referred to as meteors or for the more romantic, shooting stars.
The reason the meteor shower is called the Perseid, is because the point of the sky or radiant where the meteors appear to originate from is in the constellation of Perseus, hence Perseid.
When the Perseid meteor shower reaches its peak, up to 100 meteors an hour can be seen under ideal dark sky conditions, but in 2011 this will be greatly reduced due to a full Moon at this time. Many of the fainter meteors (shooting stars) will be lost to the glare of the Moon, but do not despair as some Perseids are bright fireballs made from larger pieces of debris, that can be golf ball size or larger.
These amazingly bright meteors can last for a few seconds and can be the brightest thing in the sky. They are very dramatic and beautiful, and seeing one can be the highlight of your Perseid observing experience.
So while expectations may be low for the Perseids this year, keep an eye out for the bright ones and the fireballs. You will not be disappointed, even if you only see one!
Join in on twitter with a worldwide event with Universe Today and Meteorwatch.org just follow along using the hashtag #meteorwatch ask questions, post images, enjoy and share your Perseid Meteor Shower experience.
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NASA’s Lunar Reconnaissance Orbiter (LRO) is changing our view of the Moon by literally bringing it into sharper focus with its three high resolution cameras. But now, things are about to get even sharper. Today, LRO fired its thrusters to begin dipping down from its usual orbit about 50 km above the surface and moving to an orbit that will allow the spacecraft’s cameras me to image the Apollo sites from about 20 km away.
“This will allow me to obtain images of the Apollo sites that are about 4 times sharper than my current best images,” said the LRO spacecraft on Twitter.
This is just a temporary orbit and the spacecraft will take images of and around the Apollo sites between August 14 and 19, 2011. After that, the spacecraft will return to the 50-km-orbit until December.
LRO has two narrow angle cameras (NACs) and one wide angle camera (WAC).
According to Mark Robinson, LROC Principal Investigator, who spoke at the Lunar Forum at Ames Research Center last month, as of the end of July, 2011 the amount of data returned by LRO has been about 400 gigabits of data every day, which includes 371,027 high resolution images. The WAC has taken about 160,000 images, with about 90,000 in color. In total, the spacecraft has imaged the entire Moon about 20 times with the WAC, and has imaged 20 per cent of the moon with NACs, which provides a narrower but higher resolution view.
“We want to map the whole moon at 50 cm/pixel to 200 cm/pixel, and that would be LROC’s legacy for the next 100 years of lunar exploration and science,” Robinson said.
He noted that all three cameras are performing way better than he had hoped.
“We are very excited about the quality of the data,” Robinson said.
So get ready for a little more quality views of the Apollo landing sites!
Update: as commenter MoonOrBust noted, the LRO Twitter feed had an addendum later in the day, adding that there are several technical challenges associated with getting improved resolution images at the lower altitude orbit. For example, the spacecraft will not slow from its orbital speed of about 1.6 km/s (about 3,500 mph) when it gets closer to the Moon’s surface, which might cause some image blurring, particularly for the LROC Narrow Angle Camera images. “However, it will certainly be fun to compare the images from the different orbits!” the spacecraft Tweeted.
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Ah, the Moon! Earth’s constant companion and the subject of songs, poetry, and many an astrophoto here on Universe Today. But we always gaze upon the Moon under the cover of Earth’s atmosphere. Does it look any different from up above the world so high? Astronauts from the ISS have taken plenty of pictures of the Moon, and here are a couple recent and notable lunar images. The one above is of a crescent Moon taken in March of this year (2011) — notice the bright crescent sliver present even while the entire moon is visible. Here, the Moon looks teeny tiny. Below is another view of a bigger, but still crescent Moon as seen from the ISS.
Expedition 28 astronaut Ron Garan took this image just a few days ago on July 31, 2011 from the International Space Station. This is such a stunning image, it was featured on NASA’s Image of the Day Gallery. Garan noted the view saying, “We had simultaneous sunsets and moonsets.” For anyone in orbit, this extraordinary event is a daily occurrence. Since the station orbits the Earth every 90 minutes, each day the crew experiences such a view about 16 times a day.
See more from Ron Garan on his Twitpic page.
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It’s a view science fiction fans could only hope for: twin moons in the night sky above Earth. But it might have been reality about 4 billion years ago. A new model suggests the lunar farside highlands could have been created from a collision with a smaller companion moon in what scientists from the University of California, Santa Cruz are calling “the big splat.”
Why the near and far sides of the Moon are so different has long puzzled planetary scientists. The near side is relatively low and flat, while the topography of the far side is high and mountainous, with a much thicker crust.
We actually have a somewhat lopsided Moon.
The new study, published in the August 4 issue of Nature, builds on the “giant impact” model for the origin of the moon, in which a Mars-sized object collided with Earth early in the history of the solar system and ejected debris that coalesced to form the moon.
According to the new computer model, the second moon around Earth would have been about 1,200 kilometers (750 miles) wide and could have formed from the same collision. Later, the smaller moon fell back onto the bigger Moon and coated one side with an extra layer of solid crust tens of kilometers thick.
“Our model works well with models of the Moon-forming giant impact, which predict there should be massive debris left in orbit about the Earth, besides the Moon itself,” said Erik Asphaug, professor of Earth and planetary sciences at UC Santa Cruz. “It agrees with what is known about the dynamical stability of such a system, the timing of the cooling of the moon, and the ages of lunar rocks.”
Other computer models have suggested a companion moon, said Asphaug, who coauthored the paper with UCSC postdoctoral researcher Martin Jutzi.
Asphaug and Jutzi used computer simulations to study the dynamics of the collision between the Moon and a smaller companion, which was about one-thirtieth the mass of the “main” moon. They tracked the evolution and distribution of lunar material in its aftermath.
The impact between the two bodies would have been relatively slow, at about 8,000 kph (5,000 mph) which is slow enough for rocks not to melt and no impact crater to form. Instead, the rocks and crust from the smaller moon would have spread over and around the bigger moon.
“Of course, impact modelers try to explain everything with collisions. In this case, it requires an odd collision: being slow, it does not form a crater, but splats material onto one side,” Asphaug said. “It is something new to think about.”
He and Jutzi hypothesize that the companion moon was initially trapped at one of the gravitationally stable “Trojan points” sharing the Moon’s orbit, and became destabilized after the moon’s orbit had expanded far from Earth. “The collision could have happened anywhere on the Moon,” Jutzi said. “The final body is lopsided and would reorient so that one side faces Earth.”
The model may also explain variations in the composition of the moon’s crust, which is dominated on the near side by terrain comparatively rich in potassium, rare-earth elements, and phosphorus (KREEP). These elements, as well as uranium and thorium, are believed to have been concentrated in the magma ocean that remained as molten rock solidified under the moon’s thickening crust. In the simulations, the collision squishes this KREEP-rich layer onto the opposite hemisphere, setting the stage for the geology now seen on the near side of the moon.
While the model explains many things, the jury is still out among planetary scientists as to the full history of the Moon and what really happened. Scientists say the best way to figure out the Moon’s history is to get more data from lunar orbiting spacecraft and – even better – sample return missions or human missions to study the Moon.
Sources: Nature, UC Santa Cruz
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CAPE CANAVERAL Fla. – Apollo 15 was the first manned lunar mission to use a lunar rover, the first of the “J” missions that would stay on the lunar surface longer and be focused on conducting science. Apollo 15 marked its 40th anniversary on Sunday. Most of the crew as well as other Apollo-era astronauts were present at the Kennedy Space Center Visitor Complex to mark the occasion.
The day’s events include a tour of the launch site at the adjacent Cape Canaveral Air Force Station. Shortly after returning to the Visitor Complex a panel discussion was held with Apollo 15 astronauts Dave Scott and Al Worden. The “moderator” for the event was none other than Apollo 12 Command Module Pilot Dick Gordon.
One thing that became quickly obvious was that the trio had done this before and were very comfortable with one another, clowning around, giving each other a hard time and telling jokes. Meanwhile, Gordon asked the two surviving Apollo 15 astronauts (the third member of the crew, James Irwin passed away in 1991) questions regarding the mission. This made learning about the importance of the mission both informative and fun. Panel discussions can be rather dry affairs – this one was lively and entertaining.
“I’ve lost control…” bemoaned Gordon as Scott and Worden talked about the mission to one another and the assembled guests.
At one point Worden was asked what the mission in general and his extra vehicular activity (EVA) was like.
“You know it’s like learning to play the piano, you practice and practice and practice and practice all week long and on Saturday you might give a recital,” Worden said. “But when the recital happens you don’t think about it – you just do it, there’s really not an emotional component to that.”
The operators of the Kennedy Space Center Visitor Complex spared little expense in ensuring that guests had a full and exciting day. The tour drove past several launch complexes including Launch Complex 34 (where the Apollo 1 fire occurred) as well as Launch Complex 39A, where the final shuttle mission launched from not too long ago. Each of the buses had the normal guide from the Visitor Complex as well as an Apollo-era astronaut, who regaled guests with various aspects of past missions. Guests also received a gift bag with several items enclosed to commemorate the occasion.
Apollo 15 launched on July 26, 1971 and ended with the splash down of the crew on Aug. 7, 1971. Scott and Irwin spent a total of three days on the moon with a little over 18 hours of that time spent on extra vehicular activity (EVA). Apollo 15 was also the first mission to not land on a lunar mare, but rather it landed near Hadley Rille, which is located around the area called Palus Putredinus (Marsh of Decay).
Having the lunar rover on this mission gave the moonwalkers the ability to traverse a far greater distance than what was possible on prior Apollo flights. While on the moon the duo collected about 170 lbs of rocks and lunar regolith. While Scott and Irwin were on the moon, Worden, circling high above in the Command Module compiled a highly detailed map of the lunar surface. A satellite was also deployed into lunar orbit on this mission (an Apollo first).
The day’s tour and panel discussion were capped off by a gala hosted by the Astronaut Scholarship Foundation. Those in attendance included Neil Armstrong as well as former Senator (New Mexico) and the first geologist to go to the moon Harrison ‘Jack’ Schmitt. Numerous other luminaries in the space field were present as well.
Those of a certain age can remember watching the footage of the Apollo 11 moonwalk live on television: the view was grainy, shadowy, and dark but it was from the Moon, which trumped everything else. Two years ago for the 40th anniversary of Apollo 11, NASA digitized and re-mastered the original footage, cleaning it up significantly. Here’s a brief montage from all the film that was cleaned up, put together by the Bad Astronomer.