Bellatrix Orionis

Here’s another Symphony of Science video.

Check out this fantastic video with Carl Sagan and Professor Stephen Hawking

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LCROSS spacecraft, artist's rendering courtesy of NASA

If you have, then you probably won’t have heard the news.  The LCROSS spacecraft has actually found water ice on the moon in a permanently shadowed crater.  Yes people please note water on the moon.

Despite the lack of an obvious visible plume when the event happend, NASA had declared the mission a success when they started receiving data.  The twin impacts were caused by the LCROSS spacecraft and a companion rocket stage which hit the Cabeus crater on 9 October 2009.  NASA reported that the plume travelled at a high angle beyond the rim of Cabeus and into the sunlight while an additional curtain of debris was ejected more laterally.  Unfortunately it wasn’t visible to us Earth based observers.

Many scientists have contemplated the source of the large quantities of hydrogen which have been observed at both of the lunar poles.  The LCROSS information is giving a new insight in the question of the discovery of water, which is possibly more widespread and in larger quantities than first thought.  It is hoped these polar cold traps could hold the key to the history and evolution of our solar system if they were formed/deposited billions of years ago.  It is also thought that this and other such compounds could be used as potential resources for future exploration of the moon.

Since the impacts the LCROSS team have been ploughing through the massive amounts of data that was collected by the spacecraft.  The data from the satellites spectrometers have provided the most definitive information regarding the presence of water.  A spectrometer is used to identify the composition of an object by examining light that is either emitted or absorbed.  The scientists used the known near-infrared spectral signatures of water as well as other materials and then compared them to the impact spectra that was collected by LCROSS.

Further confirmation was obtained via an emission in the ultraviolet spectrum which was attributed to hydroxyl, which is a product from the break up of water by sunlight.

The data obtained form other LCROSS instrument are being analysed for any further clues regarding the state and distribution of materials at the impact site.  The ultimate goal of the LCROSS science team is to understand the entire impact event as well as the distribution of all materials within the soil at the site of the impact.

The LCROSS spacecraft was launched on 18 June 2009 from Kennedy Space Centre and was a companion mission to LRO (Lunar Reconnaissance Orbiter).  LRO observed the impact and continually passes over the site of the impact to provide the LCROSS team with additional information regarding the mechanics of the impact and craters it created.  Scientists from both LCROSS, LRO and other observatories are working together to understand the data from the LCROSS impact.

For further information visit NASA’s LCROSS web pages.

Credits: NASA/CXC/Southampton/W. Ho et al.

This fantastic image from Chandra shows the central region of Cassiopeia A (also called Cas A) which is a supernova remnant that is thought to have exploded in our galaxy approximately 300 years ago.  Evidence of a neutron star with a thin carbon atmosphere has been found at the centre of Cassiopeia A.  Inset is an artists impression of how the neutron star would look complete with its carbon atmosphere.

In Chandra’s ‘First Light’ image from 1999, the point like x-ray source at the centre was presumed to be a neutron star.  This is considered to be a typical remnant of an exploded star but it did not show evidence of x-ray or radio emissions.  A model of a neutron star was applied to the object at the centre of Cassiopeia A and it was found that the region which emits x-rays would cover a typical neutron star.  Due to this x-ray pulsations would not be seen as the neutron star would not show any changes in the intensity of its rotation.  This result also provided evidence that the neutron star does not contain strange quark matter.

Because of the surface gravity being 100 billion times that of the Earth, only a very thin atmosphere has been able to form around Cassiopeia A.  Despite this the carbon atmosphere has some remarkable properties, it’s only four inches thick, but has a density similar to carbon.