LOS ANGELES -- The moon has come a long way since Galileo first peered at it through a telescope. Unmanned probes have circled around it and landed on its surface. Twelve American astronauts have walked on it. And lunar rocks and soil have been hauled back from it.
Despite being well studied, Earth's closest neighbor remains an enigma.
Over the New Year's weekend, a pair of spacecraft the size of washing machines are set to enter orbit around it in the latest lunar mission. Their job is to measure the uneven gravity field and determine what lies beneath – straight down to the core.
Since rocketing from the Florida coast in September, the near-identical Grail spacecraft have been independently traveling to their destination and will arrive 24 hours apart. Their paths are right on target that engineers recently decided not to tweak their positions.
"Both spacecraft have performed essentially flawlessly since launch, but one can never take anything for granted in this business," said mission chief scientist Maria Zuber of the Massachusetts Institute of Technology.
The nail-biting part is yet to come. On New Year's Eve, one of the Grail probes – short for Gravity Recovery and Interior Laboratory – will fire its engine to slow down so that it could be captured into orbit. This move will be repeated by the other the following day.
Engineers said the chances of the probes overshooting are slim since their trajectories have been precise. Getting struck by a cosmic ray may prevent the completion of the engine burn and they won't get boosted into the right orbit.
"I know I'm going to be nervous. I'm definitely a worrywart," said project manager David Lehman of NASA's Jet Propulsion Laboratory, which manages the $496 million, three-month mission.
Once in orbit, the spacecraft will spend the next two months flying in formation and chasing one another around the moon until they are about 35 miles above the surface with an average separation of 124 miles. Data collection won't begin until March.
Previous missions have attempted to measure lunar gravity with mixed success. Grail is the first mission dedicated to this goal.
As the probes circle the moon, regional changes in the lunar gravity field will cause them to speed up or slow down. This in turn will change the distance between them. Radio signals transmitted by the spacecraft will measure the slight distance gaps, allowing researchers to map the underlying gravity field.
Using the gravity information, scientists can deduce what's below or at the lunar surface such as mountains and craters and may help explain why the far side of the moon is more rugged than the side that faces Earth.
The probes are officially known as Grail-A and Grail-B. Several months ago, NASA hosted a contest inviting schools and students to submit new names. The probes will be christened with the winning names after the second orbit insertion, Zuber said.
Besides the one instrument on board, each spacecraft also carries a camera for educational purposes. Run by a company founded by Sally Ride, the first American woman in space, middle school students from participating schools can choose their own lunar targets to image during the mission.
A trip to the moon is typically relatively quick. It took Apollo astronauts three days to get there. Since Grail was launched from a relatively small rocket to save on costs, the journey took 3 1/2 months.
Scientists expect the mission to yield a bounty of new information about the moon, but don't count on the U.S. sending astronauts back anytime soon. The Constellation program was canceled last year by President Barack Obama, who favors landing on an asteroid as a stepping stone to Mars.
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Check out NASA's biggest discoveries of 2011.
Entire Sun Imaged
In February, <a href="http://www.nasa.gov/mission_pages/stereo/main/index.html" target="_hplink">NASA's STEREO probes</a>, two observatories that were launched in 2006 to survey the sun, reached opposite ends of the sun and thus, were able to give scientists (and the rest of us!) a never-before-seen view of the far side of the star at the center of our universe.
The composite image above was captured on June 1, 2011, <a href="http://www.nasa.gov/mission_pages/stereo/news/farside-060111.html" target="_hplink">and according to NASA</a>, "is the first complete image of the solar far side, the half of the sun invisible from Earth."
<a href="http://www.huffingtonpost.com/2011/02/07/nasa-stereo-sun-images-video_n_819510.html" target="_hplink">Click here for more</a> on the STEREO probes.
Messenger Reaches Mercury
While it's not a "discovery," <em>per se</em>, it's a milestone that will no doubt lead to many new findings about the smallest and innermost planet in our solar system.
In March, after a 6 1/2-year, 4.9 billion mile journey, <a href="http://www.huffingtonpost.com/2011/03/18/nasa-messenger-mercury_n_837503.html" target="_hplink">NASA's Messenger spacecraft reached Mercury's orbit</a>.
Messenger, the first spacecraft to orbit Mercury, <a href="http://messenger.jhuapl.edu/mer_orbit.html" target="_hplink">orbits the planet</a> every 12 hours.
In November, <a href="http://www.nasa.gov/mission_pages/messenger/media/MissionExtends.html" target="_hplink">NASA announced that the spacecraft's mission</a>, which was supposed to end on March 17, 2012, would be extended for an additional year.
Pluto's Tiny Moon
In July, NASA said that its Hubble Space Telescope <a href="http://www.huffingtonpost.com/2011/07/20/new-pluto-moon-hubble-space-telescope_n_904578.html" target="_hplink">discovered an eight to 21-mile-wide moon</a> circling the dwarf planet.
Black Hole Eats A Star
In March, <a href="http://www.huffingtonpost.com/2011/04/07/nasa-cosmic-blast_n_846333.html" target="_hplink">NASA's Swift satellite saw an unusually long explosion of gamma-rays</a>.
After studying the X-rays, <a href="http://www.huffingtonpost.com/2011/08/25/black-hole-eats-star-video_n_937150.html" target="_hplink">scientists found that they came from</a> a black hole that had become reenergized when it devoured a star.
<a href="http://www.nasa.gov/home/hqnews/2011/aug/HQ_11-271_Swift_Black_Hole.html" target="_hplink">From NASA</a>:
<blockquote>Astronomers soon realized the source, known as Swift J1644+57, was the result of a truly extraordinary event -- the awakening of a distant galaxy's dormant black hole as it shredded and consumed a star. The galaxy is so far away, it took the light from the event approximately 3.9 billion years to reach Earth. </blockquote>
Huge Mountain Discovered On Asteroid
<a href="http://www.nasa.gov/mission_pages/dawn/main/index.html" target="_hplink">NASA's Dawn</a>, an ion-propelled spacecraft that traveled 1.7 billion miles before reaching the asteroid Vesta in July, sent back images in October revealing that <a href="http://www.huffingtonpost.com/2011/10/05/vesta-mountain-dawn-nasa_n_996282.html" target="_hplink">Vesta is home to a mountain larger than any mountain</a> on Earth.
In December, NASA released new images that Dawn took when it was orbiting only 130 miles above the asteroid, the closest it will get to Vesta.
Dawn will continue to image Vesta until next summer, when it will make its way to Ceres, a bigger asteroid.
'Star Wars'-Like Planet
<a href="http://www.huffingtonpost.com/2011/09/15/kepler-16b-planet-two-suns_n_964799.html" target="_hplink">NASA's Kepler spacecraft found a planet</a> that orbits two suns, driving fans of the "Star Wars" franchise <a href="http://blog.moviefone.com/2011/09/16/astronomers-discover-real-life-tatooine-star-wars/" target="_hplink">to call it a real-life Tatooine</a>.
Astronomers announced Kepler-16b, which is the first circumbinary planet -- meaning it orbits two stars -- in September.
<a href="http://www.huffingtonpost.com/2011/09/15/kepler-16b-planet-two-suns_n_964799.html" target="_hplink">Click here for more</a> on Kepler-16b.
'Habitable Zone' Planet Found
Scientists in early December <a href="http://www.huffingtonpost.com/2011/12/05/kepler-22b-new-planet-discovered-habitable-zone_n_1129591.html" target="_hplink">announced the discovery of Kepler-22b</a>, a planet with a temperature of around 72 degrees that's in the so-called <a href="http://en.wikipedia.org/wiki/Habitable_zone" target="_hplink">"Goldilocks," or habitable zone</a>. While the temperature of the 600-light-year away planet could sustain water, it has a radius of 2.4 times that of Earth's, so <a href="http://www.huffingtonpost.com/huff-wires/20111206/us-sci-alien-planet/" target="_hplink">it's probably too big</a> to harbor life.
Biggest Black Holes Ever Discovered
Astronomers announced in early December that <a href="http://www.huffingtonpost.com/2011/12/05/black-hole-scientists-discover-huge_n_1129727.html" target="_hplink">they had found the biggest black holes to date</a>.
The massive black holes, which are 10 billion times the size of the sun, are located over 300 million light years away.
Europa's 'Great Lakes'
Scientists had long-thought that a large body of water existed under the surface of Europa, Jupiter's moon, but it was thought to be tens of miles below an icy crust.
In November, though, astronomers analyzing data from <a href="http://solarsystem.nasa.gov/galileo/" target="_hplink">NASA's Galileo spacecraft</a> found evidence that suggests blocks of ice interact with water below the surface, which could mean that nutrients and energy are moving between the underground ocean and icy shell.
<a href="http://www.ig.utexas.edu/people/staff/britneys/" target="_hplink">Britney Schmidt</a>, the lead author of the study, <a href="http://www.nature.com/nature/journal/v479/n7374/full/nature10608.html" target="_hplink">which appeared in the journal Nature</a>, said that the interaction "could make Europa and its ocean more habitable for life."
<a href="http://www.huffingtonpost.com/2011/11/17/europa-water-jupiter-moon-photo-video_n_1099463.html#s480278&title=Europa" target="_hplink">Click here to read more</a> about water on Europa.
'Bubbles' At The Edge Of Solar System
NASA's Voyager probes -- launched over 30 years ago -- found huge magnetic "bubbles" at the edge of the solar system.
"The sun's magnetic field extends all the way to the edge of the solar system," astronomer Merav Opher of Boston University <a href="http://www.nasa.gov/mission_pages/voyager/heliosphere-surprise.html" target="_hplink">said in a NASA statement</a>. "Because the sun spins, its magnetic field becomes twisted and wrinkled, a bit like a ballerina's skirt. Far, far away from the sun, where the Voyagers are, the folds of the skirt bunch up."
Voyager 1 and Voyager 2 were launched in 1977. Voyager 1 is currently 11 billion miles away and may exit our solar system within the next few years.
Gypsum On Mars
In December, scientists announced that NASA's <a href="http://www.huffingtonpost.com/2011/12/08/mars-water-opportunity-rover-gypsum_n_1136483.html" target="_hplink">Mars Rover Opportunity may have found gypsum </a>that had been deposited by water.
"This tells a slam-dunk story that water flowed through underground fractures in the rock," <a href="http://astro.cornell.edu/people/facstaff-detail.php?pers_id=112" target="_hplink">Steve Squyres</a>, a planetary scientist at Cornell University and the principal investigator for Opportunity <a href="http://www.nasa.gov/mission_pages/mer/news/mer20111207.html" target="_hplink">said in a NASA statement</a>.
NASA's Curiosity Rover <a href="http://www.huffingtonpost.com/2011/11/26/nasa-mars-curiosity-launc_n_1113995.html" target="_hplink">is en route to the Red Planet</a> and will arrive in August 2012.
Earth-Size Planets Discovered
Weeks after <a href="http://www.huffingtonpost.com/2011/12/05/kepler-22b-new-planet-discovered-habitable-zone_n_1129591.html" target="_hplink">the announcement of Kepler-22b</a>, scientists said that <a href="http://www.huffingtonpost.com/2011/12/20/new-planets-kepler-exoplanets_n_1161213.html" target="_hplink">they'd discovered Kepler-20e and Kepler-20f</a>, two planets that are about the size of Earth.
While the planets are too close to their sun-like star to harbor life as we know it, the discovery proved that the Kepler spacecraft was capable of spotting planets that are Earth-size, and brings us one step closer to finding a true Earth twin.
<a href="http://www.huffingtonpost.com/2011/12/20/new-planets-kepler-exoplanets_n_1161213.html" target="_hplink">Click here for more</a> on the new planets.
LOS ANGELES -- The moon has come a long way since Galileo first peered at it through a telescope. Unmanned probes have circled around it and landed on its surface. Twelve American astronauts have walk...
LOS ANGELES -- The moon has come a long way since Galileo first peered at it through a telescope. Unmanned probes have circled around it and landed on its surface. Twelve American astronauts have walk...
CAPE CANAVERAL, Fla. -- A pair of spacecraft rocketed toward the moon Saturday on the first mission dedicated to measuring lunar gravity and determining what's...
NASA has released never-before-seen images of three lunar landing sites. These high-resolution stills feature stunningly detailed scenes of abandoned experiment sites and trails made by...
By Marcia Dunn, The Associated Press CAPE CANAVERAL, Fla. -- Four decades after landing men on the moon, NASA is returning to Earth's orbiting companion,...
Galileo, according to his correspondent Kepler, took a major idea, without acknowledging it, from Giordano Bruno, executed a decade before Gal published on the Moon. Galileo observed an almost diseased Moon, pock-marked--which contradicted Christian teaching of the perfection of all heavenly bodies. One Jesuit critic, LaGalla, said Galileo's observations could not possibly be right.
Now, how deal with this "maculate" Moon; the Moon was supposed by Aquinas and Dante to be, like Mary, immaculate. What we now call "Sea of Tranquillity" (named in 1651 by the Jesuit Riccioli) Galileo saw as a huge Blotch, "macula." Bruno suggested heavenly bodies were like our world, so the Blotch was renamed a "Sea." Smaller blotches were called "craters," but much later (19C).
See A Powers' Worlds of Giordano Bruno, 2011.
Alan_Powers: Galileo, according to his correspondent Kepler, took a major idea,
If the readings are sensitive enough, they should be able to detect a very large underground cavern, sealed by a very large iron door, the result of an ancient underground mining operation. Visible surface evidence is a small rectangular building sitting on the floor of a large crater - on the front side, quadrant 4. There is also an operational base with many rooms, down a curving connecting tunnel, not far from the large sealed cavern.
On the back side, there is also another base, set into a hillside, with visible structures protruding including the hangar bay doors. The hangar bay is also a large empty (some of the time) hollow area. This facility has been in operation for a very long time, serving as a base of operations for earth-based activities.
We've been there 12 times before on inferior equipment and technology. So why would this be a "nail biter" of a mission? And if it's so easy to get the moon on equipment that is pretty much antique compared to today's standard, why hasn't China or Russia ever been to the moon?
kidjudas: We've been there 12 times before on inferior equipment and
Ok HuffPo either you or my computer just posted before I was done. It should have said my yearning to know mind and Nasa you have never let me down. From the splashdowns in the ocean and walking on the moon. And now such wonderful pictures of the universe we live in. It's just plain AWESOME. I cried when the last shuttle landed but I shouldn't have worried so much. The new things that Nasa is doing are just so damn amazing this is one atheist who can only say "oh my God" There just is nothing else to say. Except of course NASA YOU ROCK.
GoGrammie: Ok HuffPo either you or my computer just posted before
Nasa YOU ROCK. I get so exited by these beautiful images and just how much we have learned about the universe! I feel like a kid at Christmas. I was 12 when we landed on the moon and it made quite the impression on my yearning
GoGrammie: Nasa YOU ROCK. I get so exited by these beautiful
This mission is essentially a lunar version of the fantastically successful GRACE satellite pair that has orbited the earth for years. It can so such amazing things as measure the changing masses of the antarctic and Greenland icecaps by measuring unbelievably tiny changes in the relative accelerations of the two spacecraft.
palindrom: This mission is essentially a lunar version of the fantastically
I wonder if they will ever find the access door that leads into the hollow interior of the "Moon." They will discover that the Moon is actually an ancient Generation Ship, that brought the original human colony to Earth 50,000 years ago.
I know....but wouldn't it be cool?
Carbon_Forteetoo: I wonder if they will ever find the access door
I realize this is a lot of money to spend when we don't have any, but who isn't proud of American achievements. I know I feel great when I read what America tries to accomplish furthering science and technology. Hopefully in the near future we will be led by people that realize what it takes to keep America great!
propackage: I realize this is a lot of money to spend
We have plenty of money. We're just not spending it on things that create jobs for Americans. The people with too much money are tucking it away in financial instruments. The people will too little money are spending it on highly resource-intensive needs like food and energy or on labor-intensive commodities produced in cheap labor markets and sold at big box retailers.
We need to spend more of the excessive income on labor-intensive enterprises that are uniquely suited to the American workforce and industrial base. Aerospace is one of the things that America has always done very well. It creates well-paying middle-class jobs, promotes academic achievement, and provides sound justification for pioneering research and development.
NASA is a program that is under constant political pressure, most surprisingly from working-class Democrats. Believe it or not, support for NASA is stronger among Republicans, and NASA is particularly well-regarded by the top earners (of any politics) who bear a large part of the tax burden. The better educated and more economically savvy Americans are most likely to identify NASA as a most productive use of public finance. Even many radical libertarians agree.
Yes, we could cut NASA's measly 0.4% of the federal budget and divert it to food stamps, but I believe that in the long run, money spent on domestic skilled labor reduces the cost of social programs like food stamps. These social programs are absolutely necessary, but they should not be funded at the expense of programs that can reduce the number of Americans who must rely on them.
jsarets: We have plenty of money. We're just not spending it
RT @kaneshow If only we had more like this kid in the world: 9 year-old wins trip to Disney, donates it to family of fallen soldier: http://t.co/i1upfcgA
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By ALICIA CHANG 12/26/11 05:41 PM ET Associated Press