Spacecraft to investigate if Venus’s lack of magnetism is the cause of her inhospitable atmosphere
Scientists today revealed their plans to analyse the magnetic field around Venus in a bid to discover whether the planet’s lack of an internal magnetic field is the reason it is so inhospitable.
At a press conference in London hosted by the Particle Physics and Astronomy Research Council, Chris Carr of Imperial College London described how the magnetometer instrument onboard the Venus Express spacecraft will measure the magnetic field around the planet.
Scientists hope their results will confirm why Venus is so inhospitable in comparison to Earth and has almost no water, in spite of the similarities between the two planets. Earth and Venus formed at the same time from the same basic materials and they are very similar in size and mass.
Scientists believe that Venus is inhospitable because its atmosphere is being eroded by the ‘solar wind’, a magnetised, electrically charged gas that streams off the Sun at a million miles per hour. This ’plasma’ from the Sun slams into an electrically charged part of Venus’s atmosphere known as the ionosphere, which is ionised by solar radiation.
The ionosphere provides a magnetic barrier against the solar wind but scientists believe that this barrier has much less protective power than Earth’s internal magnetic field. This internal magnetic field creates a ’bubble’ around Earth that protects it from the solar wind.
Chris Carr, who helped to build the instrument alongside colleagues at the Space Research Institute in Austria and the Institute for Extraterrestrial Physics in Braunschweig, Germany, explained: "We are going to make a ’map’ of the plasma around Venus. By measuring the magnetic field, we can analyse the complex physical processes that result when the solar wind and Venus’s ionosphere collide."
The Venus Express magnetometer is similar to the one that the Imperial team has been involved in building and controlling onboard the Cassini spacecraft. Cassini’s magnetometer recently revealed an unexpected magnetic signature from the Saturnian moon Enceladus, a surprise which led to the discovery of an atmosphere on this tiny moon.
Chris Carr added: “We are going to be able to get a substantially enhanced picture of the space environment around Venus using the new high-resolution magnetometer, coupled with a new high-resolution plasma analyzer. We have a huge number of questions that we hope these instruments can help answer."
Even though the solar wind is travelling at such immense speeds, the Venus ionosphere still presents a significant ‘magnetic barrier’. How do these plasmas mix? How much energy is transferred from the Sun into the Venus atmosphere?” he said.
The Magnetometer for the Venus Express mission consists of two small sensors about 5cm by 5cm and weighing about 200g. One is mounted on the end of a metre-long deployable boom and the other sits directly on the spacecraft’s body. The use of two sensors means that the stray magnetic fields produced by the spacecraft can be taken into account when the team is measuring Venus’s magnetic field.
Venus Express sets off on 26th October 2005 and is due to reach Venus in April 2006.
Laura Gallagher | alfa
The most recent press releases about innovation >>>
Die letzten 5 Focus-News des innovations-reports im Überblick:
Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.
For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...
What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.
To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...
A bacterial enzyme enables reactions that open up alternatives to key industrial chemical processes
The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....
Larsen C Ice Shelf rift finally breaks through
A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...
Physics supports biology: Researchers from PTB have developed a model system to investigate friction phenomena with atomic precision
Friction: what you want from car brakes, otherwise rather a nuisance. In any case, it is useful to know as precisely as possible how friction phenomena arise –...