Capturing the sun
The sun is the centre of our solar system and supplies essential warmth and light to all life on this planet, but it is difficult to establish exactly what it is made from. Probes can’t be sent into the sun as they simply melt and readings from Earth can only tell us a limited amount.
The Planetary and Space Sciences Research Institute (PSSRI), based at the Open University, is currently involved in the NASA Genesis project, to find out more about the sun by collecting samples of solar wind, a constant stream of ions emitted by the sun.
The project involves sending up a spacecraft to just outside the magnetic effects of the earth where ions in the solar wind (which are much like tiny balls) embed themselves in the collection material and can be brought back down to Earth for analysis.
The PSSRI’s team of scientists are specifically looking for some of the less abundant elements in the sun, such as oxygen and carbon, and are using diamond as the collection material because it can be made with extremely low levels of oxygen impurities.
Genesis does not take off until the year 2001, but until that time the scientists are occupied with proving their plan will work through dry run experiments. Diamond is artificially implanted with oxygen ions and then experiments are conducted to see if they can get the same amount of oxygen out again.
If the project is successful they should be able to work out how much and what types of oxygen there are in the solar wind, and therefore how much of these types are in the sun. As the sun makes up 99% of the mass of the solar system, this will tell us a lot about what oxygen was around when the solar system was formed 4.5 billion years ago.
It will take two years for Genesis to capture enough material for analysis. On re-entry, the spacecraft will be captured in mid air by a helicopter to avoid impact damage. It is then that the long task of analysing the samples will begin.
What happened next?
This article was originally published in 2000. Subsequently, the Genesis spacecraft returned to earth in 2004. However, its parachute failed to deploy and it crashed rather than being caught in mid-air by the waiting helicopter. Fortunately the collectors with their samples of solar wind particles survived the impact.
Since our last update, some analysis of the material gathered by Genesis has taken place. In 2011, NASA revealed it implied the sun is made from different material from that which the others objects in the solar system comprise of.
Take it further
The New Solar System
J Kelly Beatty, Carolyn Collins Petersen and Andrew L Chaikin, Cambridge University Press
Beginner’s Guide to the Sun
Peter O Taylor and Nancy L Hendrickson, Kalmbach Publishing Co
Find out more about other projects at the PSSRI
Visit the homepage of the Genesis project
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