table of contents table of contents

Stardust's seven year mission is to collect samples of the interstellar dust …

Home » Biology Articles » Evolutionary Biology » Origin of Life » The Molecules that Fell to Earth » Trawling the cosmos

Trawling the cosmos
- The Molecules that Fell to Earth

Stardust's mission is to collect samples of both interstellar dust and cometary ejecta. The mission will be launched on 6 February and will last for just under seven years, during which time there will be two periods of interstellar dust collection (from March to May 2000, and July to December 2002) and an encounter with comet Wild 2 on 2 January 2004. Stardust is expected to return to Earth on 15 January 2006.

  Interstellar gas and dust in M16, the Eagle Nebula

The spacecraft will fly to within 100km of Wild 2 at a speed of about 6.1km s-1. It will collect samples by exposing sheets of aerogel to the flow of cometary and interstellar particles. Aerogel is a low-density, silica-based material composed of individual features only a few nanometres in size, linked in a highly porous dendritic structure.

Because many organic molecules are very sensitive, some will probably not survive the collection process, so an on-board mass spectrometer will also provide compositional information. However, Nasa has stated that it will make the strongest effort possible to preserve organic components in an analysable form.

Those organic samples that are returned safely will be analysed by Sandford and others, using a range of analytical techniques, including mass spectrometry, gas chromatography, chemical reaction analysis, Auger electron analysis and infrared spectroscopy.

rating: 1.75 from 4 votes | updated on: 20 Dec 2006 | views: 13826 |

Rate article: