The Apollo 13 checklist with Lovell's handwritten calculations. Image credit:
[/caption]
Former NASA astronaut Jim Lovell came under fire last week when he sold a personal memento from his tenure with the space agency at an auction – the 70-page checklist from the famous Apollo 13 mission that didn’t land on the Moon. The sale has reopened the ongoing debate over who owns NASA artifacts and photographs, the astronauts or the public.
Apollo 13 commander Lovell with a model Lunar module. Image credit: NASA
In Lovell’s case, the checklist is so valuable because it contains Lovell’s hand written calculations he used to navigate the crippled Apollo 13 spacecraft after its oxygen tank exploded. That’s a pretty important piece of history for many collectors. Bids on the historic item surpassed $388,000.
But now NASA is questioning whether Lovell had the right to sell the item and profit from its sale. For now, the checklist – along with a lunar module identification plate and a hand controller from Apollo 9 sold by former astronaut Rusty Schweickart and a glove Al Shepard wore on the Moon on Apollo 14 sold at the same auction – is locked in a Heritage Auctions vault until the issue is resolved.
NASA administrator Charles Bolden released a statement saying that there have been “fundamental misunderstandings and unclear policies” regarding items astronauts took home from the Mercury, Gemini, Apollo and Skylab mission.
These “misunderstandings and unclear policies” aren’t new. Last summer, NASA filed a lawsuit against Apollo 14 astronaut Ed Mitchell after he tried to sell a 16mm video camera he used on the Moon. NASA claimed Mitchell was selling the camera illegally and sued the former astronaut for ownership rights. Mitchell countered that the camera would have been left on the Moon had he not brought it home. It’s been sitting in his personal safe since 1971.
Mitchell isn’t wrong in his self defense. In the 1960s and 1970s, NASA officials told the astronauts that they could keep certain equipment from the missions.
In 2002, former Flight Director Chris Kraft said that he approved the policy. Apollo astronauts were allowed to keep personal items that flew with them as well anything from the lunar landing module that would otherwise have been abandoned on the Moon. The astronaut had great freedom in choosing what they wanted to keep.
Rusty Schweickart during an EVA on Apollo 9. Image credit: NASA/courtesy of nasaimages.org
“It was generally accepted that the astronauts could bring back pieces of equipment or hardware from this spacecraft for a keepsake of these journeys,” Kraft wrote.
Since the end of the space race, collectors around the world have paid millions to own pieces of history themselves. NASA’s problem isn’t with these former astronauts keeping pieces of history for themselves, it’s when they sell these artifacts for personal gain that creates a problem.
Kraft’s 2002 letter doesn’t address whether or not astronauts have the right to sell their mementos. In its recent letter to the auction house, NASA insisted only the agency can approve such artifacts for sale.
Bolden said the ownership discussions will explore “all policy, legislative and other legal means” to resolve ownership issues “and ensure that appropriate artifacts are preserved and available for display to the American people.” The agency has agreed to work cooperatively with the astronauts to resolve what’s recently become a contentious issue.
Apollo 14 Lunar Module pilot Mitchell. Image credit: NASA
It is a bit of a grey area. The astronauts did the work, they trained for difficult mission and went to the Moon. But NASA footed the bill, and American tax payers funded NASA. The space agency argues that artifacts from the Apollo era should be available to the public. Everyone should be able to view and experience these pieces of one of the nation’s historic achievements.
Wrinkle ridges, like this one in the northern part of Mare Imbrium, were studied using telescopic observations, as early as the 1880's. Data from the Apollo era refined our understanding of these interesting features. More recently, data from the Lunar Reconnaissance Orbiter Camera is calling that understanding into question. Image credit: NASA/GSFC/Arizona State University and the author Click on the image to explore the LROC data from this area in greater detail
[/caption]
Wrinkle ridges have been seen on the surface of the Moon for over a century. Studies of these interesting features began as early as 1885, with telescopic photographs, and continued beyond the Apollo era, with satellite and lander observations. Scientists thought they understood them, but the latest images from the Lunar Reconnaissance Orbital Camera (LROC) suggest we may not know the whole story.
By definition, wrinkle ridges are narrow, steep-sided ridges that form predominantly in volcanic regions. They are very complex features, which can be either straight or curved, or even be braided and zig-zagged. Their width can be anything from less than 1 km to over 20 km. And their heights range from a few meters (say the height of an average room) to 300 meters (about the height of a 100-story sky scraper). They are also asymmetric, with one side of the ridge being higher than the other. Often, these things sit on top of a gentle swell in the landscape. Features like this have been found on a number of planets throughout the Solar System, including the Moon, Mars, Mercury, and Venus.
Wrinkle ridges, like this one in the northern part of Mare Imbrium, were studied using telescopic observations, as early as the 1880's. Data from the Apollo era refined our understanding of these interesting features. More recently, data from the Lunar Reconnaissance Orbiter Camera is calling that understanding into question.
Image credit: NASA/GSFC/Arizona State University and the author
Click on the image to explore the LROC data from this area in greater detail
The earliest researchers of lunar wrinkle ridges saw them through telescopes. When looking at the terminator (the line between the dark side and the lit side of the Moon), the angle of the Sun causes spectacular shadows to highlight the topography, allowing these otherwise subtle features to be seen. Scientists in the late 19th century believed that these wrinkle ridges, which were found predominantly in the volcanic mare regions, formed when the cooling magma shrank. The chilled crust at the very top of this magma body was now too large, and wrinkles had to form to accommodate the difference. This process was often compared to the wrinkled skin of a shriveled apple, or the skin on our hands as we age.
The dawn of the space age introduced orbiting satellites, which circled the Moon collecting images that were more detailed than had been possible ever before. Data from the 1960’s the Lunar Orbiter (LO) program, whose mission was to photograph the Moon in preparation for the Apollo missions, showed many more of these wrinkle ridge features.
Some researchers felt the LO data pointed to a volcanic origin for wrinkle ridges. They saw lava flows emanating from the wrinkle ridges and embaying impact craters. They suggested that lava flowed to the surface along linear fractures that exploited zones of weakness in the lunar crust (presumably, these weaknesses formed when impacts created the basins that lunar mare occupy). Lava that extruded onto the surface formed the wrinkle ridge features, while magma that intruded below the surface formed the regional swell the ridges sit on.
The Apollo missions, however, were able to provide information about what was happening below the surface, with the Apollo Lunar Sounder Experiment (ALSE). Data collected over a wrinkle ridge in the southeastern portion of Mare Serenitatis showed that there was some kind of topographic structure beneath the thin mare layers in this area. This suggested that wrinkle ridges were the surface expressions of thrust faults in the underlying crust. This interpretation was appealing because it explained why some wrinkle ridges are found outside of mare areas.
Wrinkle ridges are generally steep-sided, asymmetric structures, displaying complex braiding or zig-zag patterns. This wrinkle ridge, in the northern mare of Tsiolkovskiy crater, is very different. Described as "bulging", it has a gently curved uniform shape. It is also much smaller than the wrinkle ridges seen before. This unusual wrinkle ridge suggests we may not understand the formation of these features as well as we thought.
Image credit: NASA/GSFC/Arizona State University
Click on the image to learn more about this discovery from NASA's LROC team.
Later, studies of wrinkle-like features on Earth refined our understanding of how these features form. Now the thinking is that wrinkle ridges form by tectonic buckling of the mare areas and their surroundings. When mare lavas are extruded on the surface of the Moon, they fill up the impact basins in a series of basalt layers. The thinned crust left by the basin-forming process can’t support the weight of the mare, so the entire structure sags. The mare layer can become decoupled from the underlying regolith (the “soil” layer that impacts created between the time the basin was formed and when the first mare lavas extruded) and slide towards the sagging centre. As it does so, it bunches up in places where the decoupling is not complete. This creates a series of thrust faults at the base of the mare layer, which show up as wrinkle ridges at the surface. This decoupling process is more pronounced for thinner mare layers, which explains why we often see wrinkle ridges at the edges of a mare.
Recent findings from the Lunar Reconnaissance Orbiter Camera (LROC) may challenge this current understanding of wrinkle ridge formation. LROC images from the mare in Tsiolkovskiy crater have identified wrinkle ridges that are considerably different from the ones seen before. For one, these wrinkle ridges are not asymmetrical in profile, but have a uniformly curved shape. Also, they are much smaller, measuring less than 100 meters in width, as opposed to the 1-20 km widths seen for other wrinkle ridges.
It remains to be seen if these new wrinkle ridges will again change our understanding of how these enigmatic features form. The discovery of these particular ridges is so new that there is nothing yet published about them! Perhaps this image and others like it will help us learn more about these enigmatic features and answer questions such as: does this new wrinkle ridge represent the beginnings of their formation process and that all such ridges started out so small and symmetrical? Or maybe we’ll find that they are extrusions of particularly viscous lava, which have barely protruded above the surface along a linear fault.
Scientists plan to target this area for further data acquisition, because only more data from LRO and further research will help solve the mysteries of the wrinkled Moon.
The Moon rises above (below?) Earth's limb in this view from the ISS. (ESA/NASA)
[/caption]
“The moon looks the same from the ISS as it does on Earth. Only we see it rise and set again and again.”
ESA astronaut André Kuipers tweeted this message earlier today, accompanied by the wonderful photo above showing a distant Moon resting along Earth’s limb. The solar panels of the docked Soyuz TMA-03M spacecraft are seen in the foreground.
André arrived at the Space Station on December 23 along with Expedition 30 crewmates Oleg Kononeko and Don Pettit.
In addition to conducting over 45 experiments for ESA, NASA and JAXA during his five months in orbit, André’s PromISSe mission will help educate children about math, science, engineering, technology, and the benefits – and challenges – of working in space.
The program will also encourage the next generation of space explorers to stay fit with the second edition of the international fitness initiative Mission X: Train Like an Astronaut.
A medical doctor, André serves as flight engineer aboard the ISS and will be highly involved in docking procedures for the new Dragon (SpaceX) and Cygnus (Orbital Sciences) capsules as part of NASA’s next-generation commercial spaceflight program.
Read ESA’s PromISSe mission blog here, and follow André Kuipers on Twitter @astro_andre for more Expedition 30 mission updates.
Ever wish you could have been a fly on the wall of the Eagle lunar module (figuratively speaking, of course) and watched Neil Armstrong and Buzz Aldrin take their first steps on the Moon in 1969? A fun new app called MoonWalking allows you to bring Tranquility Base down to Earth to watch history unfold in front of you. Using your iPhone or iPad as an interactive magic window into history, you can watch all the action, and even take pictures of the events with your iPhone. MoonWalking is an augmented-reality app that recreates Tranquility Base in your backyard or neighborhood park.
You can learn more about MoonWalking here, and you can download it from iTunes for only $.99. But Universe Today has codes to give away to the first two people who leave a comment to get the app for free. Remember, this is for iPhones and iPads only.
Moon and International Space Station from NASA Johnson Space Center, Houston, Texas. This photo was taken in the early evening of Jan. 4. Equipment: Nikon D3S, 600mm lens and 2x converter, Heavy Duty Bogen Tripod with sandbag and a trigger cable to minimize camera shake. Camera settings: 1/1600 @ f/8, ISO 2500 on High Continuous Burst. Credit: NASA
[/caption]
Has the International Space Station (ISS) secretly joined NASA’s newly arrived GRAIL lunar twins orbiting the Moon?
No – but you might think so gazing at these dazzling new images of the Moon and the ISS snapped by a NASA photographer yesterday (Jan. 4) operating from the Johnson Space Center in Houston, Texas.
Check out this remarkable series of NASA photos above and below showing the ISS and her crew of six humans crossing the face of Earth’s Moon above the skies over Houston, Texas. And see my shot below of the Moon near Jupiter – in conjunction- taken just after the two GRAIL spacecraft achieved lunar orbit on New Year’s weekend.
In the photo above, the ISS is visible at the upper left during the early evening of Jan. 4, and almost looks like it’s in orbit around the Moon. In fact the ISS is still circling about 248 miles (391 kilometers) above Earth with the multinational Expedition 30 crew of astronauts and cosmonauts hailing from the US, Russia and Holland.
Space Station Crossing Face of Moon
This composite of images of the International Space Station flying over the Houston area show the progress of the station as it crossed the face of the moon in the early evening of Jan. 4, 2012 over NASA’s Johnson Space Center, Houston, Texas. Credit: NASA
click to enlarge
The amazing photo here is a composite image showing the ISS transiting the Moon’s near side above Houston in the evening hours of Jan 4.
The ISS is the brightest object in the night sky and easily visible to the naked eye if it’s in sight.
With a pair of binoculars, it’s even possible to see some of the stations structure like the solar panels, truss segments and modules.
Check this NASA Website for ISS viewing in your area.
How many of you have witnessed a sighting of the ISS?
It’s a very cool experience !
NASA says that some especially good and long views of the ISS lasting up to 6 minutes may be possible in the central time zone on Friday, Jan 6 – depending on the weather and your location.
And don’t forget to check out the spectacular photos of Comet Lovejoy recently shot by Expedition 30 Commander Dan Burbank aboard the ISS – through the Darth Vader like Cupola dome, and collected here
Moon and International Space Station (at lower right) on Jan 4, 2012 from NASA Johnson Space Center, Houston, Texas. Credit: NASA click to emlargeMoon, Jupiter and 2 GRAILs on Jan. 2, 2012
Taken near Princeton, NJ after both GRAIL spacecraft achieved lunar orbit after LOI - Lunar Orbit Insertion- burns on New Year’s weekend 2012. Credit: Ken Kremer
The Apollo lunar landing module as it looked in 1963. Image credit: wired.com
[/caption]
When President Kennedy promised America a lunar landing in 1961, he effectively set the Moon as the finish line in the space race. In the wake of his speech, NASA began scrambling to find a way to reach the Moon in advance of the Soviet Union, which at the time held a commanding lead in space. Apollo, already on the drawing board as an Earth orbiting program, was revised to reflect the lunar goal and Gemini was established as the interim program.
The pieces were in place; all NASA needed was a way to get to the Moon. Against this pressing background, two men proposed a desperate and direct mission to get an American on the Moon as quickly as possible.
A schematic showing three different flight modes for Apollo lunar missions. Image credit: NASA
The proposal came from two Bell Aerosystems Company employees. John M. Cord was a Project Engineer in the Advanced Design Division and Leonard M. Seale was a psychologist in charge of the Human Factors Division. At the Institute of Aerospace Sciences in Los Angeles in 1962, the pair unveiled their “One-Way Manned Space Mission” proposal.
The plan called for a one-man spacecraft to follow a direct ascent path to the Moon. Ten feet wide and seven feet tall, the empty spacecraft weighed less than half the much smaller Mercury capsule. Inside, the astronaut would have enough water for 12 days, oxygen for 18 with a 12-day emergency reserve, a battery-powered suit and backpack, and all the tools and medical supplies he might need.
He would land on the Moon after a two-and-a-half day trip and have just under ten days to set up his habitat. As part of his payload, the astronaut would arrive with four cargo modules with pre-installed life support systems and a nuclear reactor to generate electrical power. Two mated modules would become his primary living quarters, while the others placed in caves or buried in rubble — a feature Cord and Seale assumed would dominate the lunar landscape — would provide a shelter from solar storms.
A possible configuration for a direct ascent Apollo spacecraft. Image credit: NASA
With his temporary home set up, he would wait a little over two years for another mission to come and collect him. Cord and Seale estimated that this mission could be launched as early as 1965, a year of expected minimal solar activity. Larger launch vehicles capable of sending the three-man Apollo spacecraft would be ready by 1967. The one-way spaceman would have a long but finite stay on the Moon.
This proposal was incredibly practical. Since the astronaut wouldn’t be launching from the lunar surface, he wouldn’t need to carry the necessary propellant. Since he would return to Earth in another spacecraft, his own spacecraft wouldn’t need a heavy heat shield or parachutes. The one-way mission was a light and efficient proposal.
But it was also dangerous. The proposal didn’t include any redundancies; the direct ascent path gave the astronaut no chance to abort his mission after launch. He would have to deal with any problems that arose knowing he wouldn’t be able to make a quick return home.
Luckily for the possible astronaut the proposal was never seriously considered. In July 1962, a few weeks after the one-way mission was proposed, NASA announced its selection of the more complicated but safer Lunar Orbit Rendezvous (LOR) mode for Apollo missions.
John Houbolt explains the benefits of Lunar Orbit Rendezvous over Direct Ascent. Image credit: NASA/courtesy of nasaimages.org
Click on the image to download the full map and explore it in more detail.
[/caption]
Was the early solar system bombarded with lots of big impacts? This is a question that has puzzled scientists for over 35 years. And it’s not just an academic one. We know from rocks on Earth that life began to evolve very early on, at least 3.8 billion years ago. If the Earth was being pummeled by large impacts at this time, this would certainly have affected the evolution of life. So, did the solar system go through what is known as the Late Heavy Bombardment (LHB)? Exciting new research, using data from the Lunar Reconnaissance Orbiter Camera (LROC) may cast some doubt on the popular LHB theory.
It’s actually quite a heated debate, one that has polarized the science community for quite some time. In one camp are those that believe the solar system experienced a cataclysm of large impacts about 3.8 billion years ago. In the other camp are those that think such impacts were spread more evenly over the time of the early solar system from approximately 4.3 to 3.8 billion years ago.
The controversy revolves around two large impact basins, which are found fairly close to each other on the Moon. The Imbrium basin is one of the youngest basins on the near side of the Moon, while the Serenetatis basin is thought to be one of the oldest. Both are flooded with volcanic basalts and are big enough to be seen from Earth with the naked eye.
What if the Apollo 17 samples didn't come from the Serenitatis basin, where the astronauts collected them, but rather from the Imbrium basin, located some 600 km away? Studies from the new Lunar Reconnaissance Orbiter Camera suggest this may be the case. If true, this means Serenitatis is much older than the Imbrium basin and a solar system-wide impact catastrophe is not needed to explain the uncannily close ages of the Imbrium and Serenitatis basins.
Image credit: NASA
Click on the image to download the full map and explore it in more detail.
Scientists know the relative ages of such lunar basins because of a concept called superposition. Basically, superposition states that what is on top must be younger than what is beneath. Using such relationships, scientists can determine which basins are older and which are younger.
To get an absolute age, though, scientists need actual bits of rock, so they can use radiometric dating techniques. The lunar samples returned by the Apollo program provided exactly that. But, the Apollo samples suggest that the Imbrium and Serenitatis basins are barely 50 million years apart.
Relative age dating tells us there are over 30 other basins that formed within that time frame. This means that roughly one major impact occurred every 1.5 million years! Now, 1.5 million years may sound like a long time. But consider the last large impact that happened on Earth, the Chicxulub event 65 million years ago, which is thought to have exterminated the dinosaurs. Imagine another 40 dinosaur-killing impacts occurring since then. It would be surprising if any life survived such a barrage!
This is why a team of researchers, led by Dr. Paul Spudis of the Lunar and Planetary Institute, is looking very carefully at this question. Their research is using the principle of superposition to show that several of the areas visited by the Apollo program were blanketed by material from the Imbrium impact. This could mean that many of the collected Apollo materials may be sampling the same event.
Dr. Spudis’s research focuses on the Montes Taurus area, between the Serenitatis and Crisium basins, not far from the Apollo 17 landing site. This is a region dominated by sculpted hills that have been interpreted to be ejected material from the adjacent Serenitatis basin impact. But, Dr. Spudis and his team have found that, instead, this sculpted material comes from the Imbrium basin some 600 kilometers away.
Previous data of this area, from the Lunar Orbiter IV camera, hadn’t shown this because a fog on the camera lens made the details difficult to see (this fog problem was eventually resolved, and Lunar Orbiter IV provided a lot of useful data on other parts of the Moon).The new LROC data, however, shows that the sculpted terrain seen at Apollo 17 is very widespread, extending far beyond the Montes Taurus region. Furthermore, the grooves and lineated features of this terrain point to the Imbrium basin, not the Serenitatis basin, and line up with similar features in the Alpes and Fra Mauro Formations, which are known to be ejecta from the Imbrium impact. In the north of Serenitatis, these Imbrium formations even seem to transform into the Montes Taurus, confirming that the sculpted hills do, in fact, originate from the Imbrium impact.
Recent high quality data from the Lunar Reconnaissance Orbiter Camera shows that the sculpted terrain, which is present at the Apollo 17 landing site, is related to material that is known to be from the Imbruim impact. This means that Apollo 17 may have sampled Imbrium and not Serenitatis material. This could explain the unusually close ages of these two basins, suggested by the Apollo samples. If so, the Serenitatis impact may have occurred much earlier than previously thought, meaning that a barrage of frequent bombardments did not occur, and life on Earth could have evolved without being molested by too many impact events.
Image credit: NASA/GSFC/Arizona State University
Click on the image to explore the LROC data in greater detail.
If the sculpted hills are Imbruim ejecta, then it is possible that Apollo 17 sampled Imbrium and not Serenitatis materials. That casts suspicion on the very close radiometric ages of these two basins. Perhaps these ages are so close because we effectively measured the same material. In that case, the age of Serenitatis could be much older than the 3.87 billion years the Apollo 17 samples suggest. If true, this would mean that there was no Late Heavy Bombardment at the time life was forming on the early Earth, leaving life to evolve with relatively few impact-related interruptions.
Titan and Dione seen on December 10, 2011 by the Cassini spacecraft. (NASA/JPL/SSI/J. Major)
[/caption]
It’s been said many times that the most Earthlike world in our solar system is not a planet at all, but rather Saturn’s moon Titan. At first it may not seem obvious why; being only a bit larger than the planet Mercury and coated in a thick opaque atmosphere containing methane and hydrocarbons, Titan sure doesn’t look like our home planet. But once it’s realized that this is the only moon known to even have a substantial atmosphere, and that atmosphere creates a hydrologic cycle on its surface that mimics Earth’s – complete with weather, rain, and gully-carving streams that feed liquid methane into enormous lakes – the similarities become more evident. Which, of course, is precisely why Titan continues to hold such fascination for scientists.
Now, researchers have identified yet another similarity between Saturn’s hazy moon and our own planet: Titan’s energy budget is in equilibrium, making it much more like Earth than the gas giant it orbits.
A team of researchers led by Liming Li of the Department of Earth and Atmospheric Sciences at the University of Houston in Texas has completed the first-ever investigation of the energy balance of Titan, using data acquired by telescopes and the Cassini spacecraft from 2004 to 2010.
Energy balance (or “budget”) refers to the radiation a planet or moon receives from the Sun versus what it puts out. Saturn, Jupiter and Neptune emit more energy than they receive, which indicates an internal energy source. Earth radiates about the same amount as it receives, so it is said to be in equilibrium… similar to what is now shown to be the case for Titan.
Blue hazes hover high above thicker orange clouds over Titan's south pole (NASA/JPL/SSI)
The energy absorption and reflection rates of a planet’s – or moon’s! – atmosphere are important clues to the state of its climate and weather. Different balances of energy or changes in those balances can indicate climate change – global cooling or global warming, for instance.
Of course, this doesn’t mean Titan is a balmy world. At nearly 300 degrees below zero (F) it has an environment that even the most extreme Earth-based life would find inhospitable. Although Titan’s atmosphere is ten times thicker than Earth’s its composition is very different, permitting easy passage of infrared radiation (a.k.a. “heat”) and thus exhibits an “anti-greenhouse” effect, unlike Earth or, on the opposite end of the scale, Venus.
Still, some stable process is in place on Saturn’s moon that allows for distribution of solar energy across its surface, within its atmosphere and back out into space. With results due in from Cassini from a flyby on Jan. 2, perhaps there will soon be even more clues as to what that may be.
The team’s report was published in the AGU’s Geophysical Research Letters on December 15, 2011. Li, L., et al. (2011), The global energy balance of Titan, Geophys. Res. Lett., 38, L23201, doi:10.1029/2011GL050053.
Take a good close look at the Moon today and consider this; Two new Moon’s just reached orbit.
NASA is ringing in the New Year with a double dose of champagne toasts celebrating the back to back triumphal insertions of a pair of tiny probes into tandem lunar orbits this weekend that seek to unravel the hidden mysteries lurking deep inside the Moon and figure out how the inner solar system formed eons ago.
Following closely on the heels of her twin sister, NASA’s GRAIL-B spacecraft ignited her main braking rockets precisely as planned on New Year’s Day (Jan.1) to go into a formation flying orbit around the Moon, chasing behind GRAIL-A which arrived on New Year’s Eve (Dec. 31).
“Now we have them both in orbit. What a great feeling!!!!” NASA manager Jim Green told Universe Today just minutes after the thruster firing was done. Green is NASA’s Director of Planetary Science and witnessed the events inside Mission Control at the Jet Propulsion Laboratory (JPL) in Pasadena, Ca.
“It’s the best New Year’s ever!!” Green gushed with glee.
GRAIL-B spacecraft entered Lunar Orbit on New Year’s Day 2012. Artist concept of GRAIL-B performing its lunar orbit insertion burn. Credit: NASA/JPL-Caltech
The new lunar arrivals of GRAIL-A and GRAIL-B capped a perfect year for NASA’s Planetary Science research in 2011.
“2011 began the Year of the Solar System – which is a Mars year (~670 Earth days long)… and includes Grail B insertion, Dawn leaving Vesta this summer … And the landing of MSL! ,” Green said.
NASA’s GRAIL-A & GRAIL-B are orbiting the Moon in this image taken on Jan. 2, 2012 after Lunar Orbit Insertions on New Year’s Weekend. Click to enlarge.
Credit: Ken Kremer
“Cheers in JPL mission control as everything is looking good for GRAIL-B. It’s going to be a great 2012!!” JPL tweeted shortly after confirming the burn successfully placed GRAIL-B into the desired elliptical orbit.
After years of hard work, GRAIL principal investigator Maria Zuber of MIT told Universe Today that she was very “relieved”, soon after hearing the good news at JPL Mission Control.
“Since GRAIL was originally selected I’ve believed this day would come,” Zuber told me shortly after the GRAIL-B engine firing was declared a success on New Year’s Day.
“But it’s difficult to convey just how relieved I am right now. Time for the Science Team to start their engines !”
Artist's concept depicts how the science instrument on the mirror image twin GRAIL spacecraft will send signals to each other to map the Moon's gravity and then transmit the data to Earth. Credit: NASA
At 2:43 p.m. PST (5:43 p.m. EST) on New Year’s Day, the main thruster aboard GRAIL-B automatically commenced firing to slow down the spacecraft’s approach speed by about 430 MPH (691 kph) and allow it to be captured into orbit by the Moon’s gravity. The preprogrammed maneuver lasted about 39 minutes and was nearly identical to the GRAIL-A firing 25 hours earlier.
The hydrazine fueled main thrusters placed the dynamic spacecraft duo into near-polar, highly elliptical orbits.
Over the next two months, engineers will trim the orbits of both spacecraft to a near-polar, near-circular formation flying orientation. Their altitudes will be lowered to about 34 miles (55 kilometers) and the orbital periods trimmed from their initial 11.5 hour duration to about two hours.
The science phase begins in March 2012. For 82 days, the mirror image GRAIL-A and GRAIL-B probes will be flying in tandem with an average separation of about 200 kilometers as the Moon rotates beneath.
“GRAIL is a Journey to the Center of the Moon,” Zuber explained at a media briefing. “It will use exceedingly precise measurements of gravity to reveal what the inside of the Moon is like.”
As one satellite follows the other, in the same orbit, they will perform high precision range-rate measurements to precisely measure the changing distance between each other to within 1 micron, the width of a red blood cell, using a Ka-band instrument.
When the first satellite goes over a higher mass concentration, or higher gravity, it will speed up slightly. And that will increase the distance. Then as the second satellite goes over, that distance will close again.
The data returned will be translated into gravitational field maps of the Moon that will help unravel information about the makeup of the Moon’s mysterious core and interior composition. GRAIL will gather three complete gravity maps over the three month mission.
“There have been many missions that have gone to the Moon, orbited the Moon, landed on the Moon, brought back samples of the Moon,” said Zuber. “But the missing piece of the puzzle in trying to understand the Moon is what the deep interior is like.”
“Is there a core? How did the core form? How did the interior convect? What are the impact basins on the near-side flooded with magma and give us this Man-in-the-Moon shape whereas the back side of the Moon doesn’t have any of this? These are all mysteries that despite the fact we’ve studied the Moon before, we don’t understand how that has happened. GRAIL is a mission that is going to tell us that.”
“We think the answer is locked in the interior,” Zuber elaborated.
How will the twins be oriented in orbit to gather the data ?
“The probes will be pointed at one another to make the highly precise measurements,” said GRAIL co-investigator Sami Asmar of JPL to Universe Today. “The concept has heritage from the US/German GRACE earth orbiting satellites which mapped Earth’s gravity field. GRACE required the use of GPS satellites for exactly knowing the position, but there is no GPS at the Moon. So GRAIL was altered to compensate for no GPS at the Moon.”
GRAIL will map the gravity field by 100 to 1000 times better than ever before.
“We will learn more about the interior of the Moon with GRAIL than all previous lunar missions combined,” says Ed Weiler, the recently retired NASA Associate Administrator of the Science Mission Directorate in Washington, DC.
The GRAIL twins blasted off from Florida mounted side by side atop a Delta II booster on September 10, 2011 and took a circuitous 3.5 month low energy path to the Moon to minimize the overall costs.
So when you next look at the sky tonight and in the coming weeks just imagine those mirror image GRAIL twins circling about seeeking to determine how we all came to be !
GRAIL Project manager David Lehman cuts the cake for team members at JPL to celebrate 2 for 2 at the Moon. Credit: NASA/Jim GreenGRAIL team at JPL toasts success as twin spacecraft both went into orbit around the Moon on New Year’s weekend.
GRAIL-A and GRAIL-B flying in tandem using a precision formation-flying technique. Credit: NASA
[/caption]
Cheers erupted after the first of NASA’s twin $496 Million Moon Mapping probes entered orbit on New Year’s Eve (Dec. 31) upon completion of the 40 minute main engine burn essential for insertion into lunar orbit. The small GRAIL spacecraft will map the lunar interior with unprecedented precision to deduce the Moon’s hidden interior composition.
“Engines stopped. It’s in a great initial orbit!!!! ”
NASA’s Jim Green told Universe Today, just moments after verification of a successful engine burn and injection of the GRAIL-A spacecraft into an initial eliptical orbit. Green is the Director of Planetary Science at NASA HQ and was stationed inside Mission Control at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Ca (see photos below).
“Pop the bubbly & toast the moon! NASA’s GRAIL-A spacecraft is in lunar orbit,” NASA tweeted shortly after verifying the critical firing was done. “Burn complete! GRAIL-A is now orbiting the moon and awaiting the arrival of its twin GRAIL-B on New Year’s Day.”
The firing of the hydrazine fueled thruster was concluded at 5 PM EST (2 PM PST) today, Dec. 31, 2011 and was the capstone to a stupendous year for science at NASA.
“2011 was definitely the best year ever for NASA Planetary Science,” Green told me today. “2011 was the “Year of the Solar System”.
“GRAIL-A is in a highly elliptical polar orbit that takes about 11.5 hours to complete.”
“We see about the first eight to ten minutes of the start of the burn as it heads towards the Moon’s southern hemisphere, continues as GRAIL goes behind the moon and the burn ends about eight minutes or so after it exits and reappears over the north polar region.”
“So we watch the beginning of the burn and the end of the burn via the Deep Space Network (DSN). The same thing will be repeated about 25 hours later with GRAIL-B on New Year’s Day [Jan 1, 2012],” Green explained.
The orbit is approximately 56-miles (90-kilometers) by 5,197-miles (8,363-kilometers around the moon. The probe barreled towards the moon at 4400 MPH and skimmed to within about 68 miles over the South Pole.
“My resolution for the new year is to unlock lunar mysteries and understand how the moon, Earth and other rocky planets evolved,” said Maria Zuber, GRAIL principal investigator at the Massachusetts Institute of Technology in Cambridge. “Now, with GRAIL-A successfully placed in orbit around the moon, we are one step closer to achieving that goal.”
Zuber witnessed the events in Mission Control along with JPL Director Charles Elachi (see photos).
GRAIL team at JPL Mission Control celebrates successful insertion of GRAIL-A into Lunar Orbit of New Year’s Eve. From Left: David Lehman, GRAIL Project Manager of JPL, Prof Maria Zuber, GRAIL Principal Investigator of MIT, Charles Elachi, JPL Director. Credit: NASA/Jim Green
The mirror twin, known as GRAIL-B, was less than 30,000 miles (48,000 km) from the moon as GRAIL A achieved orbit and closing at a rate of 896 mph (1,442 kph). GRAIL-B’s insertion burn is slated to begin on New Year’s Day at 2:05 p.m. PST (5:05 p.m. EST) and will last about 39 minutes.
GRAIL-B is about 25 hours behind GRAIL-A, allowing the teams enough time to rest and prepare, said David Lehman, GRAIL project manager at JPL.
“With GRAIL-A in lunar orbit we are halfway home,” said Lehman. “Tomorrow may be New Year’s everywhere else, but it’s another work day around the moon and here at JPL for the GRAIL team.”
GRAIL-A spacecraft achieved Lunar Orbit Insertion on New Year’s Eve. Artists concept shows twin GRAIL spacecraft orbiting the Moon. GRAIL-A and GRAIL-B flying in tandem using a precision formation-flying technique. Credit: Lockheed Martin
Engineers will then gradually lower the tandem flying satellites into a near-polar near-circular orbital altitude of about 34 miles (55 kilometers) with an average separation of about 200 km. The 82 day science phase will begin in March 2012.
“GRAIL will globally map the moon’s gravity field to high precision to deduce information about the interior structure, density and composition of the lunar interior. We’ll evaluate whether there even is a solid or liquid core or a mixture and advance the understanding of the thermal evolution of the moon and the solar system,” explained GRAIL co-investigator Sami Asmar to Universe Today. Asmar is from JPL.
New names for the dynamic duo may be announced on New Year’s Day. Zuber said that the winning names of a student essay contest drew more than 1000 entries.
The GRAIL team is making a major public outreach effort to involve school kids in the mission and inspire them to study science. Each spacecraft carries 4 MoonKAM cameras. Middle school students will help select the targets.
“Over 2100 Middle schools have already signed up to participate in the MoonKAM project,” Zuber told reporters.
“We’ve had a great response to the MoonKAM project and we’re still accepting applications.”
MoonKAM is sponsored by Dr. Sally Ride, America’s first female astronaut. The first images are expected after the science mission begins in March 2012.
The GRAIL twins blasted off from Florida on September 10, 2011 for a 3.5 month low energy path to the moon so a smaller booster rocket could be used to cut costs.
GRAIL team at JPL Mission Control await GRAIL-A Lunar Orbit Insertion on New Year’s Eve. David Lehman, GRAIL Project Manager of JPL, Prof Maria Zuber, GRAIL Principal Investigator of MIT. Credit: NASA/Jim GreenGRAIL Science and Launch teams inside clean room at Astrotech. Credit: Ken KremerGRAIL-A and GRAIL-B twin spacecraft inside clean room at Astrotech
GRAIL Co-Investigator Sami Asmar (left) from JPL and Ken Kremer discuss science objectives inside Astrotech clean room prior to encapsulation for launch. Credit: Ken Kremer
