09 October 2009

Astronomers and space enthusiasts around the world are preparing to watch Nasa crash a rocket into the lunar surface this afternoon.

The 2.2tonne rocket that launched the Lunar Crater Observation and Sensing Satellite (LCROSS) will create 'a dimple' a third the size of a football pitch on the Moon at 12.31pm (BST).

The LCROSS probe will follow four minutes later and fly through the plume of debris looking for ice and water. It will relay this data back to Earth before smashing itself. Anyone can watch the event online through the Nasa TV website. Live coverage begins at 11.15am (BST).

The probe and rocket separated in the early hours of this morning. LCROSS then tweeted on its Twitter page: 'Good bye Centaur. Thanks for an interesting ride. Now go do good work & kick up some dirt!'

The probe then applied its 'brakes' by burning fuel for just over four minutes. They are both heading for a crater in the Cabeus region near the Moon's South Pole.

The event will be visible to amateur astronomers across parts of the United States, where it will still be dark. They will need a minimum of a 10in telescope to view the six-mile high plume thrown up from the initial impact.

'The initial explosions will probably be hidden behind crater walls, but the plumes will rise high enough above the crater's rim to be seen from Earth,' said Brian Day, the Outreach Officer on LCROSS.

'This is a wonderful opportunity for citizen scientists to join Nasa in the process of discovery.'

Approximately 350 tonnes of material will be propelled into the sunlight and break down to their basic components, so scientists can study the composition using ground-based telescopes and the Hubble Space Telescope.

'If there's water there, or anything else interesting, we'll find it,' says Tony Colaprete, the mission's principal investigator.

The event comes just weeks after exciting research revealed widespread water on the surface of the Moon.

The Moon Mineralogy Mapper on board India's Chandryaan-1 picked up the electromagnetic radiation signature of water on and a few inches below the surface. Surprisingly the signal was emitted from sunlit areas as well as near the two poles. This was confirmed by two other spacecraft.

Dr Vincent Eke, from Durham University, has helped Nasa decide where to crash the probes in search of water.

He identified the Cabeus crater as a site with high concentrations of hydrogen - a key element in water.

According to the findings, water in the form of ice could be found in the frozen confines of the Moon's polar craters where temperatures are colder than -170C.

Dr Eke said: 'Water ice could be stable for billions of years on the Moon provided that it is cold enough.

'If ice is present in the permanently shaded lunar craters of the Moon then it could potentially provide a water source for the eventual establishment of a manned base on the Moon.

'Such a base could be used as a platform for exploration into the further reaches of our solar system.'

Dr Eke said people should not worry about the effect the collision could have on the Moon.

He added: 'The rocket has roughly the mass of a Transit van and it will hit the Moon at about 5,600mph. The energy of the collision is roughly equivalent to two tonnes of TNT.

'While this sounds dramatic, the impact of this will simply create one more dimple on the moonscape.

'The cratered surface of the Moon shows it has a history of violent collisions with asteroids and comets. Such collisions frequently occur, but the difference is that this time we know precisely where and when to look.'

Dr Eke's previous research showed that hydrogen was concentrated in the permanently shaded craters of the Moon's polar regions.

If hydrogen is present as water ice, then the data would imply the top metre of the surface in these craters holds about 200,000 million litres of water in total.

Preparation for impact comes as stunning thermal images of the far side of the Moon have been revealed for the first time.

The British-made Thermoteknix camera is onboard the LCROSS, and will be one of the instruments that will study the first plume of debris before crashing itself.

'The camera has worked flawlessly for nearly 100 days, and counting, in interplanetary space,' said Anthony Colaprete, payload manager and chief scientist for Nasa's LCROSS mission.

'It provided the first thermal images of the far side of the moon and also images of Earth and the Moon from distances as great as 560,000km and 850,000 km away, respectively.'

The MIRICLE camera was developed by pioneering thermal imaging company Thermoteknix Systems, based in Cambridge.

Dr Richard Salisbury, managing director of Thermoteknix, said: 'We are delighted to have been selected to play a critical part in Nasa's important mission to find water on the Moon, which is vital for the future of longterm space exploration.

'We are all very proud of this achievement.'

 

Source: Mail Online