EU Probe crashes into Moon's surface
Pastor Dale Morgan
*EU Probe crashes into Moon's surface*
Mission update
Europe's lunar satellite, the Smart 1 probe, has ended its mission by
crashing onto the Moon's surface in a controlled collision.
It was a spectacular end for the robotic probe, which has spent the last
16 months testing innovative and miniaturised space technologies.
Smart 1 has also produced detailed maps of the Moon's chemical make-up,
to help refine theories about its birth.
At 0542 GMT (0642 BST), the probe thumped into a volcanic lunar plain.
With an impact speed of about 7,200km/h (4,500mph), even at an expected
glancing blow of just one degree to the surface, the probe should have
met a sufficiently violent end for telescopes to observe the event from
Earth.
Smart 1 was returning pictures as it plunged towards the Lake of
Excellence. Controllers and scientists at the European Space Agency
(Esa) operations centre in Darmstadt, Germany clapped and cheered after
the spacecraft smacked into the surface.
Flash as Smart 1 crashes Image: Canada-France Hawaii Telescope.
Astronomers in Hawaii observed a flash as Smart 1 crashed
"As planned, Smart 1 has landed," said Professor Bernard Foing, the
mission's project scientist from Esa.
The Canada France Hawaii Telescope on Mauna Kea, in Hawaii captured an
infrared picture of a bright flash as Smart 1 hit its target.
"I was really surprised as the flash was very impressive. I was betting
on not seeing much," said Gerhard Schwehm, mission manager for Smart 1.
The hope now is that the impact will have kicked up a big enough plume
of fresh lunar "soil" for scientists to study its composition using
ground telescopes.
The impact was expected to leave a 3m by 10m crater on the Moon,
spreading debris over 78 sq km (30 sq miles).
Smart 1 impact schematic (BBC)
"We know a lot about the Moon, but there are things we need to know more
precisely if we are to embark on ambitious projects like those the US
has planned," Dr Schwehm told the BBC News website.
A fleet of spacecraft - both orbiters and landers - are now expected to
visit the Moon in the next few years.
This train of robotic explorers will culminate in US space explorers
returning to the lunar surface for the first time since the Apollo
missions, probably in 2020.
Smart 1 was launched on an Ariane-5 rocket in September 2003 as a
technology demonstrator.
It became Europe's first space science mission to use an ion engine
instead of chemical combustion to reach its destination.
GIANT IMPACT THEORIES
Suggest Mars-sized object crashed into early Earth
Debris thrown into space aggregated into the Moon
Evidence in similar composition of Earth and Moon rocks
Smart will tell how much Earth is in the Moon and vice versa
The system draws power through the probe's solar wings and then uses
this energy to propel the spacecraft forward by expelling charged
particles of xenon. It was highly efficient, covering 100 million km in
a series of looping orbits and using just 60 litres of "fuel".
"It will take a long time for it to work through the detail, the devil
is in the detail with the X-ray instruments," said Smart 1 scientist
Professor Manuel Grande of the University of Wales, Aberystwyth.
"You won't see any pictures coming straight through as we head towards
the ground. But when we finally put the picture together what we will
get is maps of what the Moon is made of."
Professor Grande has been principal investigator on one of Smart's
miniaturised instruments: the compact X-ray spectrometer known as D-CIXS.
SMART'S SPACE GAINS
Mini-instruments, navigation and operational software to go on future
Solar System probes
Smart-like solar-electric engines to become the dominant propulsion system
Data improves Moon knowledge - history of impacts and volcanism; good
landing sites
It has made mineral maps of the Moon's composition, looking at the
distribution of calcium, magnesium, aluminium, silicon and iron.
Knowing the absolute abundances of these elements will help to refine
theories for the Moon's formation. These describe the satellite emerging
from the debris thrown out from a mighty collision between Earth and a
Mars-sized body billions of years ago.
"Smart 1 will now rest in peace on the Moon," said Professor Foing.
"We are now collaborating with the international community, preparing
the way for the future exploration of the Moon - the next fleet of
orbiters, landers; leading to robotic villages and human bases."
On Saturday, mission controllers had to raise Smart 1's orbit by 600m
(2,000ft) to avoid hitting a crater rim on final approach. Had the orbit
not been raised, the craft would have crashed one orbit too soon -
making the impact difficult or impossible to observe.