NASA starts New Year with mission to the moon
LOS ANGELES (AP) - The cruise to the moon took 31/2 months and
covered 21/2 million miles - far longer than the direct three-day flight
by Apollo astronauts.
Over the New Year's weekend, a pair of NASA spacecraft arrived
back-to-back at their destination in the first mission devoted to
studying lunar gravity.
Mission controllers at the NASA Jet Propulsion Laboratory did not
toast champagne - there's a no alcohol policy on campus - but several
belatedly heralded the new year by with noisemakers.
"We can start celebrating the new year now," project manager David
Lehman said Sunday after attending a post-mission fete where cake and
sparkling cider were served.
|
NASA image shows an artist’s concept
of the Gravity Recovery and Interior Laboratory (GRAil0
mission’s twin spacecraft in orbit around the moon.
-Reuters/NASA |
The tricky arrivals occurred 24 hours apart. The drama unfolded on
New Year's Eve when Grail-A flew over the south pole, fired its engine
and dropped into lunar orbit. Its twin Grail-B repeated the manoeuvres
on New Year's Day.
Cheers and applause filled mission control when each probe signalled
it was healthy and circling the moon.
"Everything worked much better than I hoped," Lehman said.
The moon has long been an object of fascination. Galileo spotted
mountains and craters when he peered at it through a telescope. Poets
and songwriters looked to the moon as a muse.
Since the late 1950s, more than 100 missions launched by the United
States, Soviet Union, Japan, China and India have targeted Earth's
companion. NASA flew six Apollo missions that landed twelve men on the
lunar surface and brought back more than 800 pounds of rock and soil
samples.
Despite all the visits, the moon remains mysterious. Mission chief
scientist Maria Zuber of the Massachusetts Institute of Technology said
researchers know more about Mars, which is farther away from the Earth,
than the moon.
One of the enduring puzzles is its lopsided shape with the far side
more hilly than the side that always faces Earth. Research published
earlier this year suggested that our planet once had two moons that
crashed early in the solar system's history and created the moon that
hangs in the sky today.
Scientists expect to learn more about how the celestial body formed
using Grail's gravity measurements that will indicate what's below the
surface.
Since the washing machine-size Grail probes - short for Gravity
Recovery And Interior Laboratory - were squeezed on a small rocket to
save on costs, it lengthened the trip and took them 30 times longer to
reach the moon than the Apollo astronauts.
Previous spacecraft have attempted to study the moon's gravity -
about one-sixth Earth's pull - with mixed success. Grail was expected to
give scientists the most detailed maps of the moon's uneven
gravitational field and insight into its interior down to the core.
Data collection won't begin until March after the near-identical
spacecraft refine their positions and are circling just 34 miles above
the surface.
While scientists focus on gravity, middle school students will get
the chance to take their own pictures of the moon using cameras aboard
the probes as part of a project headed by Sally Ride, the first American
woman in space.
There's already chatter about trying to extend the $496 million
mission, which was slated to end before the partial lunar eclipse in
June.
Scientists initially did not think the solar-powered probes would
survive that long, but changed their minds during the long cruise to the
moon after getting new data.
Researchers expect Grail to return a plethora of data, but that
information won't be a guide to manned lunar trips anytime soon. The
Obama administration last year scrapped a plan to return astronauts to
the lunar surface in favour of landing on an asteroid as a stepping
stone to Mars.
|