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The operations team for the Lunar Crater Observation and Sensing Satellite (LCROSS) mission has discovered the spacecraft experienced an anomaly, causing it to use up a substantial amount of its fuel. According to spacecraft data, the LCROSS Internal Reference Unit (IRU) experienced a fault. The IRU is a sensor used by the spacecraft’s attitude control system (ACS) to determine the orientation and trajectory of the spacecraft. The anomaly caused the spacecraft ACS to switch to the Star Tracker Assembly for spacecraft positional information and caused the spacecraft’s thruster to fire excessively, consuming a substantial amount of fuel. Initial estimates, however, indicate that the spacecraft still contains sufficient fuel to complete the full mission.
LCROSS is scheduled to impact the lunar south pole in early October.
The team discovered the problem during a communications pass with the spacecraft on August 22, 2009. Mission operations declared a ‘spacecraft emergency’ and were allocated additional communications time on the Deep Space Network. The team conducted procedures to mitigate the problem and were able to restart the IRU and reduce fuel consumption to a nominal level. Automatic operations procedures also were implemented to minimize the possibility of another IRU anomaly from occurring while the spacecraft is out of contact with the ground.
Thankfully, since the re-start of the IRU, the spacecraft has not experienced any additional problems.
The team continues to actively assess and mitigate the situation and is in contact with the manufacturers of the IRU and star tracker to investigate the root cause of the problems. Mission managers remain optimistic the LCROSS mission can reach its successful conclusion with projected impact at the lunar south pole currently set for 4:30 a.m. PDT on Oct. 9, 2009.
LCROSS launched with the Lunar Reconnaisance Orbiter on June 18, 2009. The main LCROSS mission objective is to confirm the presence or absence of water ice in a permanently shadowed region near a lunar pole. Learn more about LCROSS and LRO here.
Cropped image of LRO's image from Apollo 14 landing site and Cone Crater. Tracks from the astronauts can be seen. Click for larger version.
During the second EVA of the Apollo 14 mission on the moon, astronauts Alan Shepard and Edgar Mitchell had a goal of hiking to the rim of nearby Cone Crater in the Fra Maura highlands. But the steep terrain made the going difficult, elevating the astronauts’ heart rates. Additionally, without landmarks it was difficult to judge distances. With the rolling terrain, filled with similar-looking ridges, Shepard and Mitchell couldn’t really tell if they were close to the rim or not.
Realizing time and available oxygen were getting short, Mission Control told the astronauts to head back to the Lunar Module, and although disappointed, the astronauts agreed. But how close did they actually come to the crater? No one knew for sure, until now.
Annotated figure showing the positions of various landmarks surrounding the Apollo 14 landing site. The small white arrows highlight locations where the astronauts’ path can be clearly seen [NASA/GSFC/Arizona State University].
One of the latest images from the Lunar Reconnaissance Orbiter shows new details of the Apollo 14 landing site. If you look closely at the image above, visible are the tracks from the astronauts steps and their three-wheeled MET cart, and you can clearly follow the trail of the astronauts on their “radial traverse.” Click the image for larger version if you’re having trouble seeing the tracks. Their tracks stop just 30 meters short of the rim, near a dark spot just to the lower left of the crater, which might be Saddle Rock, shown in the image below. Shepard and Mitchell never realized just how close they really were.
This photograph shows Saddle Rock, the largest boulder seen on this mission. Named for its shape, Saddle Rock is 4.5 meters across. Credit: NASA
On the LROC (Lunar Reconnaissance Orbiter Camera) website, Samuel Lawrence notes that more and different detail is visible on this image as opposed to the initial images released prior to the Apollo 11 anniversary in July because the lighting is different. “This time the Sun is 24 degrees higher above the horizon providing a clearer view with fewer shadows. Albedo contrasts are greater, and more clearly show soil disturbances from landing, astronaut surface operations, and blast off.”
The MET cart from Apollo 14. Credit: NASA
Lawrence notes how the term “radial traverse” does not quite do the crew of Apollo 14 justice.
“Their journey sounds like a stroll in the park, however the reality is quite the contrary. The hike up Cone crater was quite challenging. For the first time, astronauts traveled out of the sight of their lunar module while hiking uphill over 1400 meters with only a poor map, dragging the tool cart (MET), and wearing their bulky spacesuits. It was an amazing feat that the two astronauts made it to the top of Cone ridge and acquired all their samples. They ended up about 30 meters shy of peering into Cone crater itself, surely a disappointment at the time, but absolutely no reflection on the success of the traverse and the scientific results gleaned after the mission.”
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Another milestone for the Mars Exploration Rovers: Spirit has been operating on Mars for 2000 sols, or Martian days. Who would have ever thought the rovers would last this long? But here they are, still going, um, pretty strong. Even though she’s got plenty of electrical power, Spirit is currently stuck in loose soil at her location, called Troy. But engineers are working hard to figure out how to set her free. Check out the latest on the efforts at the Free Spirit website.
Artists concept of the Planck spacecraft. Credit: JPL
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As of August 13, 2009, the Planck mission is officially in business. It is now seeing light billions of years old, left over from the Big Bang. From its location in the L2 point, the spacecraft started collecting science data as part of the “First Light Survey” which is intended to check out all the systems. If all goes as planned, these observations will be the first of 15 or more months of data gathered from two full-sky scans.
Researcher Chris North wrote on the Planck website that “the major science results will take quite a while to come out due to the immense amount of computation needed to analyse them, and are expected in around 3 years’ time. These results will be a full-sky map of the Cosmic Microwave Background, and more accurate measurements of the parameters which have governed how our Universe has evolved.”
The mission, which is led by the European Space Agency with important participation from NASA, will help answer the most fundamental of questions: How did space itself pop into existence and expand to become the universe we live in today? The answer is hidden in ancient light, called the cosmic microwave background, which has traveled more than 13 billion years to reach us. Planck will measure tiny variations in this light with the best precision to date.
After the 15 month prime mission, Planck will continue to scan the sky until its coolant runs out.
A radioisotope thermalelectric generator schematic. Source: Internet Encyclopedia of Science
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As if things weren’t tight enough at NASA, now the US House and Senate have decided to cut the funding to restart production of plutonium-238 (Pu-238), the power source for many of NASA’s robotic spacecraft. Under the Atomic Energy Act of 1954, only the US Department of Energy is allowed to possess, use and produce nuclear materials and facilities, and so NASA must rely on the DOE to produce these power sources and the fuel. A report by the National Research Council says “the day of reckoning has arrived” and that NASA has already been forced to limit deep space missions due to the short supply of Pu-238.
Pu-238 is needed for radioisotope thermoelectric generators (RTGs) that supply power for systems and instruments on spacecraft travel too far from the Sun to rely on solar energy or land on surfaces with long “nights.” For example, the Voyager spacecraft utilize RTGs and are still able to communicate and return science data after over 30 years of operation, and now are at the outer edges of our solar system. Pellet of Pu-238. RTGs are constructed using marshmallow-sized pellets of Pu-238. As it decays, interactions between the alpha particles and the shielding material produce heat that can be converted into electricity.
Pu-238 is expensive to produce, but it gives off low-penetration alpha radiation, which is much easier to shield against than the radiation produced by other isotopes.
Pu-238 does not occur in naturally, and the United States has not produced any since the late 1980s. It purchased Pu-238 for NASA missions from Russia during the 1990s, but those supplies reportedly are now exhausted. The NRC based its estimate of NASA’s Pu-238 requirements on a letter NASA sent to DOE on April 29, 2008 detailing space science and lunar exploration missions planned for the next 20 years.
The cost of restarting production appears to be the major reason for the cut, as estimates are it would cost at least $150 million.
The DOE requested $30 million in FY2010 to restart production, but the House cut that to $10 million when it passed the FY2010 Energy and Water appropriations bill (H.R. 3183) on July 17. The Senate went even further (S. 1436), completely cutting funds for restarting production of Pu-238.
Both the House and Senate Appropriations Committees complained that DOE had not explained how it would use the funds.
But if funds aren’t made available soon, NASA may have to revamp its plans significantly for the New Frontiers missions, lunar rovers, and other deep space missions. There are other isotopes that have been used in the past, such as strontium-90, but Pu-238 has been found to work the best. NASA has also solicited ideas for alternative power sources, as well.
First results from the Kepler mission. Credit: NASA
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NASA researchers have published confirmation this week that the Kepler mission will be able to reveal the presence of Earth-sized planets around Sun-like stars. The mission’s first scientific results appear today in the journal Science.
Lead author William Borucki, of NASA Ames Research Center in Moffett Field, California, and his colleagues announced that Kepler has detected the giant extrasolar planet HAT-P-7b, one of the roughly two dozen exoplanets that have been discovered by ground-based observations and the CoRoT mission as they “transited” in front of their stars, periodically dimming the starlight.
Many more exoplanets — more than 300 now — have been detected by the so-called “wobble” or radial velocity method, where a planet’s gravitational tug influences the motion of its star.
HAT-P-7b is comparable to Jupiter in size and orbits a star analogous to our Sun. It showed up in 10 days’ worth of Kepler data on the intensity of light from over 50,000 stars.
“The detection of the occultation without systematic error correction demonstrates that Kepler is operating at the level required to detect Earth-size planets,” the authors write.
The $500 million Kepler mission launched in March 2009 and will spend three and a half years surveying more than 100,000 sun-like stars in Cygnus-Lyra.
By staring at one large patch of sky for the duration of its lifetime, Kepler will be able to watch planets periodically transit their stars over multiple cycles, allowing astronomers to confirm the presence of planets and use the Hubble and Spitzer space telescopes, along with ground-based telescopes, to characterize their atmospheres and orbits. Earth-size planets in habitable zones would theoretically take about a year to complete one orbit, so Kepler will monitor those stars for at least three years to confirm the planets‘ presence.
Astronomers estimate that if even one percent of stars host Earth-like planets, there would be a million Earths in the Milky Way alone. If that’s true, hundreds of Earths should exist in Kepler’s target population of 100,000 stars.
Scientists in the Lunar Receiving Laboratory. Credit: NASA
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Even though scientists have been able to study Moon rocks up close for almost 40 years, there are still many answers to be gleaned from the lunar samples collected by the Apollo astronauts. “We know even more now and can ask smarter questions as we research these samples,” says Randy Korotev from Washington University in St. Louis. “There are still some answers, we believe, in the Apollo 11 mission.” One possible clue the Moon rocks could provide is a better understanding of Earth’s history and when life actually began on our planet.
Korotev has been mainly interested in studying the impact history of the moon, how the moon’s surface has been affected by meteorite impacts and the nature of the early lunar crust.
“You can look at the moon and know that the moon has been hit a lot by very large meteorites,” he said. “We know this occurred some 3.9 billion years ago. We don’t know, however, the history of large meteorites hitting the Earth — we can’t see those impacts because they would have been erased by Earth’s active geology. We want to see if meteorite bombardment on the moon coincided with what was happening on Earth, and, in turn, with life starting on Earth.”
Recently, Korotev and his colleagues decided to begin taking a closer look at the Apollo samples to learn more about the Moon’s impact history. He says they still have much work to do with his samples, which have been chemically analyzed and are sealed in tubes and securely stored away for now.
Korotev expects the Apollo Moon rocks will provide scientific study for years to come, as our technology and understanding of the Moon improves. “We went to the moon and collected samples before we knew much about the moon,” he said. “We didn’t totally understand the big concept of what the moon was like until early 2000 as a result of missions that orbited the moon collecting mineralogical and compositional data.”
“Bringing samples back from the Moon wasn’t the point of the mission,” added Korotev. “It was really about politics. It took scientists like Bob Walker to bring these samples back — to show the value of them for research.”
Korotev credits Walker, also from Washington University and a handful of other scientists for the fact that there are even moon samples to study.
“Bob convinced them to build a receiving lab for the samples and advised them on the handling and storage of them. We didn’t go to the moon to collect rocks, so we scientists are really lucky that we have this collection.”
See Universe Today’s article on the history of the Lunar Receiving Lab.
Researchers in WUSTL's Laboratory for Space Sciences in Arts & Sciences have a long tradition of being among the first in the world to receive samples from a NASA mission. In this photo taken in 1969, the late Robert M. Walker, Ph.D., the McDonnell Professor of Physics and first director of the university's McDonnell Center for the Space Sciences in Arts & Sciences, displays photos and lunar samples from the Apollo 11 mission that year. Credit: WUSTL
Walker was recruited to serve on the scientific team that advised NASA on the handling and distribution of moon rocks and soil samples from the first Apollo missions. That team distributed Apollo 11 samples to some 150 laboratories worldwide, including Washington University, St. Louis (WUSTL).
Walker also briefed those early astronauts about what to expect on the rocky, dusty moon surface.
In an interview some months after the first moon samples arrived in WUSTL’s space sciences lab, Walker recalled the excitement of that momentous day in 1969: “We felt just like a bunch of kids who were suddenly given a brand new toy store … there was so much to do, we hardly knew where to begin.”
Ghislaine Crozaz, Ph.D., professor of earth and planetary sciences emerita in Arts & Sciences at Washington University and a member of Walker’s space sciences group that was one of those selected to study the first lunar samples, says the event is “as vivid in my mind as if it had happened yesterday.”
Crozaz says that the team studied the cosmic rays and radiation history of the lunar samples mainly using nuclear particle tracks, which were revealed by techniques invented by Walker.
“After we received the samples in early September, we worked like hell until the First Lunar Science Conference in early January 1970 in Houston, where we arrived with our Science paper after having worked ‘incommunicado’ for 4 months.”
In their study of the lunar materials, Walker’s laboratory led the way in deciphering their record of lunar, solar system and galactic evolution. Of special importance was the information they gave on the history of solar radiation and cosmic rays.
Crozaz says the lunar samples provided insights into the history of the solar system that couldn’t be achieved at the time by looking at meteorites found on Earth. The intense heat encountered during their passage through the atmosphere would have erased much of the record of radiation the meteorites carried.
Seven Apollo astronauts gathered at NASA headquarters this morning to commemorate the 40th anniversary of Apollo 11’s lunar landing — on July 20, 1969.
“This is really a national celebration,” said James Lovell, who flew on Apollo 8 and 13. “This is really a celebration for all the people who helped Neil and Buzz and Mike” make the trip to the moon, he said.
But the press conference was bittersweet, as all of the astronauts seemed to agree the space program has not gone where they hoped it would, in the years since that pinnacle of achievement. “I don’t think there was a soul in NASA that wouldn’t have thought we would have been on Mars by the year 2000,” said Walt Cunningham, from Apollo 7.
Among the astronauts, there seemed to be seven different opinions about how to get back on track.
Eugene Cernan, from Apollo 10 and 17, advocated going back to the moon, setting up bases and new telescopes. “The ultimate goal is truly to go to Mars,” he said.
Charles Duke from Apollo 16 says we need to develop better space suits. “Lunar dust, I think, is going to be a real problem,” he said, adding that air locks shoudl be developed to keep lunar dust outside any living quarters.
Buzz Aldrin has different notions altogether: “Why not do those [projects] at the space station?” he mused. “Prolong the life of the space station. We put 100 billion into the space station.” Aldrin questions the rationale that going back to the moon is a logical next step to Mars, since the physical environment on Mars will be different.
The astronauts seemed all over the map about the International Space Station as well, with some questioning its usefulness to science and its expense, and others optimistic that its glory days haven’t yet begun.
Several of the astronauts pointed out that Mars exploration has hit a new and encouraging stride, but all of them also seem to agree that space exploration needs a shot in the arm in terms of both funding, and the will of the people — especially young people.
“Everyone knows who John Glenn is, Neil Armstrong … I defy almost every one in this room to name one or two or three members on the space station today,” Cernan said. “We need to re-inspire that kind of spirit in the minds and hearts — the passion — of these kids.”
Other Universe Today Apollo 11 40th anniversary stories:
Magnificent Desolation, the new autobiography by Buzz Aldrin
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I very much enjoyed chatting with Buzz Aldrin a couple of weeks ago, for some stories leading up to the 40th anniversary of the July 20, 1969 Apollo 11 landing on the moon. I found him honest, personable and generous with his time.
But when his publicist offered to send a copy of his new book, “Magnificent Desolation,” I didn’t set my expectations too high. I didn’t know what to make of an autobiography by a retired Air Force pilot and astronaut. Doesn’t that history put the “Rocket Hero” pretty squarely in the category of techie or a jock — a non-writer type?
Well, color me impressed. The book arrived late last week, and I turned the last page this morning — looking for more to read!
Courtsey of Buzz Aldrin
Granted, Aldrin got help when he teamed up with writer Ken Abraham. But no writer can spin a book like “Magnificent Desolation” without an incredible story, and Aldrin is a master of that.
The book opens with a few chapters on the Apollo program that made him famous. Even though I’ve dabbled in some research the past few weeks — including catching up on the movie “In the Shadow of the Moon” and leafing through some books — I learned new details both whimsical and serious.
Who knew, for example, that American astronauts traditionally eat steak and eggs prior to launch? Or that Aldrin is such a font of deep thoughts, which has apparently been true for a long time:
“From space there were no observable borders between nations, no observable reasons for the wars we were leaving behind,” he remembers musing as the Earth got smaller in Apollo 11’s windows.
“Magnificent Desolation” is about as revealing as you can get in personal realms. Aldrin engages in a lengthy discussion of his decade of deep depression and alcoholism following the Apollo years, from which he eventually escaped. At his rock bottom, Aldrin had lost faith in himself, had no vision for his purpose in life, and was failing at his job — as a salesman of Cadillacs.
During our interview, Aldrin said he turned his life around by deciding that he could share his experiences for a greater good.
“Do you continue to descend into an abyss? Or do you try to make a difference with what you know best?” he remembers thinking.
These days, Aldrin lives a life fitting for a hero. He hobnobs with greats in every field, from journalists and athletes to international leaders, scientists and movie stars. He and his wife, Lois, have traveled the world for scuba diving excursions, ski trips and unflagging efforts to promote his primary passion (besides Lois): a return to the collective national motivation that helped fuel the lunar landings. He desperately wants to see America lead the charge toward space exploration — to Mars and/or a moon of Mars, and beyond.
Aldrin admits he’s been criticized in the past, even by some of his astronaut peers, for garnering so much publicity as the second man (after Neil Armstrong) to set foot on the moon.
“The truth was, no other astronaut, active or inactive, was out in the public trying to raise awareness about America’s dying space program. None of them,” he writes. He points out that he is not promoting himself: “I did not want ‘a giant leap for mankind’ to be nothing more than a phrase from the past.”
Besides pushing for a new era of space exploration, the book is also a testament to the benefits of citizen space travel, which Aldrin avidly promotes through his outreach efforts, including his non-profit Sharespace Foundation. Among them: “The United States will capture the lion’s share of the global satellite market,” and “NASA’s planetary probes will become far more affordable.”
Aldrin has used traditional channels to advance his ideas, addressing international audiences of all stripes and testifying before Congress. But the really fun stuff comes when he reaches out to younger audiences. He seems to stop at nothing to reach out to the next generations, to ensure that his space exploration dreams will stay alive.
“I look forward to these things happening during my lifetime,” he writes, “but if they don’t, please keep this dream alive; please keep going; Mars is waiting for your footsteps.”
This review is cross-posted at the writer’s website, anneminard.com.
Artist concept of Chandrayaan-1 orbiting the moon. Credit: ISRO
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The Chandrayaan 1 spacecraft, India’s moon orbiting satellite was almost lost earlier this year, Indian Space Research Organization revealed, as the star tracking system overheated and malfunctioned. The system helps determine and maintain the spacecraft’s orientation. Engineers were able to patch in the gyroscopes and another instrument to help maneuver the spacecraft, but they are not sure how long this jury-rigged system will work. At this point, determining the spacecraft’s future might be difficult, and differing statements from various officials reflect that.
“We are not sure how long we will be able to sustain it. The life of Chandrayaan-I designed for two years may be reduced,” said ISRO spokesman S. Satish.
ISRO chief Madhavan Nair said the star tracking system cannot be recovered, but he dismissed suggestions that the sensor’s failure might reduce the life span of the spacecraft.
“The life (of the spacecraft) is not dependent on this instrument. This instrument is used only for orientation of the spacecraft,” he said. “The sensor cannot be recovered at this stage and we hope that the remaining part of this mission will be completed.”
Chandrayaan-1 launched in October 2008 and suffered from overheating shortly after it began operations in lunar orbit in November, but the ISRO was able to change the spacecraft’s orientation and cut down on the amount of time the instruments were used to compensate.
In May 2009, however, officials unexpectedly raised the orbit of the spacecraft. At that time officials said they had completed mission objectives from 100 km above the moon and raised the height of the spacecraft to 200 km to enable imaging lunar surface with a wider swath. But reports say that May is when the star tracker system malfunctioned, as well.
Nair said the star sensor is suspected to have failed because of “excessive radiation” from the Sun. He said gyroscopes are not susceptible for the kind of radiation that the sensor was subjected to. “So, we hope it will survive the remaining mission duration”.
He added more than 90 percent of the two-year mission’s objectives have already been achieved.
ISRO Scientists hope the Chandrayaan project will boost India’s capacity to build more efficient rockets and satellites, especially through miniaturization, and open research avenues for young Indian scientists. India plans to follow the Chandrayaan, which means “moon craft” in Sanskrit, by landing a rover on the moon in 2011.
