A European spacecraft now
orbiting the Moon could turn out to be a time machine of sorts as it photographs
old landing sites of Soviet robotic probes and the areas where American Apollo
crews set down and explored.
New imagery of old Apollo
touchdown spots, from the European Space Agency's (ESA) SMART-1
probe, might put to rest conspiratorial thoughts that U.S. astronauts didn't
go the distance and scuff up the lunar landscape. NASA carried out six piloted
landings on the Moon in the time period 1969 through 1972.
Fringe theorists have said
images of the waving flag -- on a Moon with no atmosphere -- and other oddities
show that NASA never
really went to the Moon. No serious scientist or spaceflight historian doubts
the success of the Apollo program, however.
"We are observing some
of the landing sites for calibration and ground truth purposes," said Bernard
Foing, Chief Scientist of the ESA Science Program.
Foing told SPACE.com
that the SMART-1 orbiter circling the Moon has already covered the Apollo 11,
16, 17 landing sites, as well as spots where the former Soviet Union's Luna
16 and Luna 20 automated vehicles plopped down. The images have not yet been
released.
Detailed search planned
Given SMART-1's initial
high orbit, however, it may prove difficult to see artifacts, Foing explained.
Using its ion engine, the probe has successfully spiraled down further to an
altitude closer to the Moon.
Foing said that each Apollo
site, where the engine blast of the two-person landing craft stirred up the
landscape, could be worthwhile targets for SMART-1 imaging.
"We shall search for
them, with measurements not only in black and white, but also in three colors
giving some information about minerals, weathering or [rocket engine] plume
disturbance," he said.
SMART-1 operators also plan
sequences that keep the probe's camera specially trained on some landing sites
as it sweeps overhead, Foing said. Along with these observations and others,
the spacecraft will also be busy gleaning data in preparation for future international
lunar exploration missions, he emphasized.
SMART-1 arrived in lunar
orbit last November. Last month, ESA announced that the lunar mission would
be extended by one year, pushing back the mission end date from August 2005
to August 2006.
The extension permits stereo
measurements of select areas of interest. Doing so, topography maps of specific
lunar real estate can be created. Mapping prospective landing
sites for future robotic and human
missions are possible too.
Why not Hubble?
If SMART-1 can get an eyeful,
why not use the Hubble space telescope to take photos of the Apollo landing
sites? Hubble did photograph the Moon, in 1999.
"Anything left on the Moon
cannot be resolved in any Hubble image," According to the Space Telescope Science
Institute, which operates Hubble for NASA. "It would just appear as a dot."
Meanwhile, the trickiest
task that the SMART-1 scientists have set themselves is to use a spacecraft
spectrometer to look for the infrared signature of water ice, and perhaps frozen
carbon dioxide and carbon monoxide too. Previous missions have provided evidence
for water ice tucked away in permanently shadowed polar craters.
Any water on the lunar surface
would be very helpful in the creation of permanent
bases on the Moon, as outlined last year by President Bush. Other nations
have Moon
plans, too.
But to have survived, the
water must be in the form of ice in places always hidden from the Sun. Such
dark places exist, notably in the bottoms of small craters in the Moon's polar
regions.