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Probe crashes into Moon's surface Probe crashes into Moon's surface
(10 minutes later)
Europe's lunar satellite, the Smart 1 probe, has ended its mission by crashing onto the Moon's surface in a controlled collision.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.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.Smart 1 has also produced detailed maps of the Moon's chemical make-up, to help refine theories about its birth.
At about 0542 GMT (0642 BST), the probe crashed into a volcanic plain.At about 0542 GMT (0642 BST), the probe crashed into a volcanic 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 astronomers to observe the event from Earth.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 astronomers to observe the event from Earth.
Astronomers are now analysing a plume of fresh lunar "soil", or regolith, kicked up by the crash. They have also been looking for the bright flash as the probe hit the surface. The impact was expected to leave a 3m by 10m crater on the Moon's surface, spreading debris over 78 sq km (30 sq miles).Astronomers are now analysing a plume of fresh lunar "soil", or regolith, kicked up by the crash. They have also been looking for the bright flash as the probe hit the surface. The impact was expected to leave a 3m by 10m crater on the Moon's surface, spreading debris over 78 sq km (30 sq miles).
There are places on the Moon that always see sunshine 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 the European Space Agency (Esa)."As planned, Smart 1 has landed," said Professor Bernard Foing, the mission's project scientist from the European Space Agency (Esa).
Gerhard Schwehm, Smart 1 mission manager, said: "Everything worked up until the end, so it was a wonderful mission and a big success. Our spacecraft provided a lot of new information."Gerhard Schwehm, Smart 1 mission manager, said: "Everything worked up until the end, so it was a wonderful mission and a big success. Our spacecraft provided a lot of new information."
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.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.
A fleet of spacecraft - both orbiters and landers - are now expected to visit the Moon in the next few years.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.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.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.It became Europe's first space science mission to use an ion engine instead of chemical combustion to reach its destination.
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".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".
Smart 1 has made mineral maps of the Moon's composition, looking at the distribution of calcium, magnesium, aluminium, silicon and iron.Smart 1 has made mineral maps of the Moon's composition, looking at the distribution of calcium, magnesium, aluminium, silicon and iron.
GIANT IMPACT THEORIES Suggest Mars-sized object crashed into early EarthDebris thrown into space aggregated into the MoonEvidence in similar composition of Earth and Moon rocksSmart will tell how much Earth is in the Moon and vice versa "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.GIANT IMPACT THEORIES Suggest Mars-sized object crashed into early EarthDebris thrown into space aggregated into the MoonEvidence in similar composition of Earth and Moon rocksSmart will tell how much Earth is in the Moon and vice versa "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.""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.Professor Grande has been principal investigator on one of Smart's miniaturised instruments: the compact X-ray spectrometer known as D-CIXS.
It has made mineral maps of the Moon's composition, looking at the distribution of calcium, magnesium, aluminium, silicon and iron.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.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."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.""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."
An ion engine will now be fitted to the majority of Europe's future spacecraft, such as the BepiColumbo mission to Mercury.An ion engine will now be fitted to the majority of Europe's future spacecraft, such as the BepiColumbo mission to Mercury.
HOW SMART 1'S ION ENGINE WORKS 1. Xenon gas atoms are pumped into a cylindrical chamber, where they collide with electrons from the cathode. The electrons - which are negatively charged - knock electrons off the xenon atoms, creating xenon ions - which are positively charged.2. Coils outside the chamber create a magnetic field, which causes electrons from the cathode to spiral and become trapped at the mouth of the chamber.3. The build-up of negatively charged electrons at the mouth of the chamber attracts the positively charged ions, accelerating them out of the chamber.4. The stream of accelerated ions leaving the chamber thrusts the spacecraft forward. Although the force is small, over time it creates great speed in the frictionless environment of space.HOW SMART 1'S ION ENGINE WORKS 1. Xenon gas atoms are pumped into a cylindrical chamber, where they collide with electrons from the cathode. The electrons - which are negatively charged - knock electrons off the xenon atoms, creating xenon ions - which are positively charged.2. Coils outside the chamber create a magnetic field, which causes electrons from the cathode to spiral and become trapped at the mouth of the chamber.3. The build-up of negatively charged electrons at the mouth of the chamber attracts the positively charged ions, accelerating them out of the chamber.4. The stream of accelerated ions leaving the chamber thrusts the spacecraft forward. Although the force is small, over time it creates great speed in the frictionless environment of space.