Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A comet’s tale at Diamond

08.09.2008
A new picture of the composition of comets is emerging with the help of 21st century technology available at Diamond, the UK’s national synchrotron light source, in Oxfordshire.

We already know that comets played a significant role in ensuring that conditions were right for life on Earth. Most of the icy, small planetary bodies that otherwise became comets went into forming the gas giant planets in the outer Solar System but some were ejected from the vicinity of the largest planets.

Of these, a fraction ended up in the inner Solar System bringing water and biogenic elements of interest to Earth. Without this cometary transport, life on Earth may never have had a chance to start.

Now, scientists from the Space Research Centre at the University of Leicester have, for the first time, brought samples of the Comet Wild-2 to Diamond. In doing so, using Diamond’s microfocus spectroscopy capabilities – bright and powerful X-rays with a beam size equivalent to one 25th of a human hair – they have discovered that the old model of comets as dusty iceballs is not the whole picture.

Dr John Bridges, from the Space Research Centre, explains the results, ‘Comets are starting to look a lot more complicated than the old dusty iceball idea. For one thing Wild-2 contains material, like chromium oxides, from the hot inner Solar System – so how did that material get mixed in with a comet which has spent most of its life beyond Neptune? It suggests that there has been major mixing of material from inner and outer parts of the Solar System in its earliest stages.

‘At Diamond, we have also been finding X-ray signatures of iron oxides. These are important because they show that on the Wild-2 nucleus there could have been small trickles of water that deposited these minerals. Similar grains are found in carbonaceous chondrite meteorites. This might mean that there have been localised heating events perhaps caused by impact on the Wild-2 nucleus that melted some of its ice.’

Their samples, which were born in the Kuiper Belt near Neptune, were collected by the Stardust space mission, which involved a seven year long, five billion km, journey. They then travelled by more conventional means (Fedex) from the US to the Space Research Centre. The Stardust mission was conceived so that comets could be studied directly as this will help researchers to find out more about the Solar System’s water and the dust that escaped planetary formation.

Dr Bridges adds, ‘It’s now becoming clear that not all comets are the same. For instance, Wild-2 may have more similarities to some asteroids and primitive meteorites than comets from the Oort Cloud, which extends to the outer limits of our Solar System and which are infrequent visitors to Earth.’

Diamond is capable of studying a huge variety of samples from every discipline of scientific research. Dr Fred Mosselmans, Principal Beamline Scientist for Diamond's microfocus spectroscopy beamline, says, ‘In the past year, example of samples studied have included wood chips from the Mary Rose warship, paint pigment samples from Tate Britain, brain tissue to further our understanding of Parkinson's disease, metal on metal hip replacements, stainless steel corrosion and the comet grains from the Stardust mission – a reflection of the huge breadth of research undertaken at Diamond.’

The University of Leicester team plan to study more cometary tracks at Diamond in the months to come, from which they will be able to establish accurate comparisons with meteorites and determine the processes – such as liquid water in the nucleus and mixing in material from the hot inner Solar System – that have gone towards forming comets.

Researchers can contact scientists to discuss their experiment ideas and then put a proposal together for beamtime. An international scientific review panel considers all proposals before allocating time on one of our beamlines. Diamond currently has 11 operating beamlines, with a further 11 being added between now and 2012.

Diamond is supporting the BA Festival of Science which will take place in Liverpool from 6-11 September. The Festival brings over 350 of the UK’s top scientists, engineers and commentators to discuss the latest developments in science with the public. In addition to talks and debates at the University of Liverpool, there will be a host of events happening throughout the city as part of the European Capital of Culture celebrations.

For more information about the BA Festival of Science, including an online programme, visit www.the-ba.net/festivalofscience.

This year’s BA Festival of Science is organised by the BA (British Association for the Advancement of Science) in partnership with the University of Liverpool. It is supported by the Department for Innovation, Universities & Skills, the Liverpool Culture Company and the Northwest Regional Development Agency.

Lisa Hendry | alfa
Further information:
http://www.diamond.ac.uk
http://stardust.jpl.nasa.gov/home/index.html
http://www.the-ba.net

More articles from Physics and Astronomy:

nachricht A tale of two pulsars' tails: Plumes offer geometry lessons to astronomers
18.01.2017 | Penn State

nachricht Studying fundamental particles in materials
17.01.2017 | Max-Planck-Institut für Struktur und Dynamik der Materie

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

A big nano boost for solar cells

18.01.2017 | Power and Electrical Engineering

Glass's off-kilter harmonies

18.01.2017 | Materials Sciences

Toward a 'smart' patch that automatically delivers insulin when needed

18.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>