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US lunar probes set to blast off US lunar probes set to blast off
(10 minutes later)
Nasa is set to launch two spacecraft to the Moon in preparation for a return to the lunar surface by US astronauts.Nasa is set to launch two spacecraft to the Moon in preparation for a return to the lunar surface by US astronauts.
LRO (Lunar Reconnaissance Orbiter) and a crater observation mission will lift off from Florida on an Atlas V rocket.LRO (Lunar Reconnaissance Orbiter) and a crater observation mission will lift off from Florida on an Atlas V rocket.
Data gathered by LRO will help mission planners select future landing sites and scout locations for lunar outposts.Data gathered by LRO will help mission planners select future landing sites and scout locations for lunar outposts.
The second mission will send a rocket stage crashing into the lunar surface to scour the resulting debris plume for evidence of water ice.The second mission will send a rocket stage crashing into the lunar surface to scour the resulting debris plume for evidence of water ice.
The Atlas rocket, carrying both payloads, is scheduled to blast off from Florida's Cape Canaveral Air Force Station at 2212 BST (1712 local time) on Thursday.The Atlas rocket, carrying both payloads, is scheduled to blast off from Florida's Cape Canaveral Air Force Station at 2212 BST (1712 local time) on Thursday.
LRO will enter a low polar orbit around the Moon at an altitude of around 50km (31 miles) - the closest any spacecraft has continually orbited Earth's natural satellite.LRO will enter a low polar orbit around the Moon at an altitude of around 50km (31 miles) - the closest any spacecraft has continually orbited Earth's natural satellite.
It will map the lunar surface in unprecedented detail and is expected to enhance our understanding of the Moon's topography, mineral composition and lighting conditions.It will map the lunar surface in unprecedented detail and is expected to enhance our understanding of the Moon's topography, mineral composition and lighting conditions.
The mission will also seek to characterise the Moon's radiation environment, helping mission planners assess the risks posed to astronauts.The mission will also seek to characterise the Moon's radiation environment, helping mission planners assess the risks posed to astronauts.
The second mission, the Lunar Crater Observation and Sensing Satellite (LCROSS), consists of two elements: a shepherding spacecraft and a Centaur upper stage rocket. The second mission, the Lunar Crater Observation and Sensing Satellite (LCROSS), is designed to search for water in the form of ice or hydrated minerals. It consists of two elements: a shepherding spacecraft and a Centaur upper stage rocket.
After being guided to a permanently shadowed crater at the Moon's south pole by its shepherding spacecraft, the Centaur rocket separates.After being guided to a permanently shadowed crater at the Moon's south pole by its shepherding spacecraft, the Centaur rocket separates.
It will kick up a huge plume of debris when it hits the Moon.It will kick up a huge plume of debris when it hits the Moon.
Four minutes later, the shepherding spacecraft follows a very similar path to the rocket, descending through the plume.Four minutes later, the shepherding spacecraft follows a very similar path to the rocket, descending through the plume.
It will use its instruments to analyse the material, searching for water ice and vapour, hydrocarbons and hydrated materials.It will use its instruments to analyse the material, searching for water ice and vapour, hydrocarbons and hydrated materials.
The spacecraft will collect data continuously until it too slams into the lunar surface.The spacecraft will collect data continuously until it too slams into the lunar surface.
Nasa said the two impacts will excavate some 500 metric tons of lunar material.Nasa said the two impacts will excavate some 500 metric tons of lunar material.
Any natural reserves of water will figure prominently in planning for future manned lunar bases. It can be split into hydrogen for rocket fuel and oxygen for breathing and makes an excellent shield against radiation.Any natural reserves of water will figure prominently in planning for future manned lunar bases. It can be split into hydrogen for rocket fuel and oxygen for breathing and makes an excellent shield against radiation.
The US space agency hopes to send astronauts back to the Moon by 2020 for the first manned visit since 1972.The US space agency hopes to send astronauts back to the Moon by 2020 for the first manned visit since 1972.
However, the Obama administration has ordered a sweeping independent review of Nasa's manned spaceflight strategy, which could potentially set the agency on a different course.However, the Obama administration has ordered a sweeping independent review of Nasa's manned spaceflight strategy, which could potentially set the agency on a different course.