Press Conference 1

Date: Thursday 4 September
Venue:  Dana Centre, London
Contacts: Silvana Damerell, 07841 432780 and Sarah Bucknall, 07920 296957

Media release from the BA (British Association for the Advancement of Science)

Embargo: 00.01 Monday 8 September 2008

A comet’s tale at Diamond

A new picture of the composition of comets is emerging with the help of 21^st 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 25^th 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.

ENDS

For interviews, pictures or more information on Diamond’s experiments, please contact Sarah Bucknall on 01235 778639 or [email protected] or visit http://www.diamond.ac.uk.

For suitable images, visit ftp://managed_ftp.diamond.ac.uk/BA%20Festival%20images/

For information about the BA Festival of Science, please contact Lisa Hendry on 020 7019 4946 or [email protected] or visit http://www.the-ba.net/festivalofscience.

For animations on how an experiment takes place and films clips, please visit Diamond’s YouTube page at http://uk.youtube.com/user/DiamondLightSource

For more information on the department of Physics at the University of Leicester, please visit www.star.le.ac.uk/xra

Notes to Editors

 

1. The BA Festival of Science 2008 is being 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. Find out more at www.the-ba.net/festivalofscience. To register for access to the press papers or to the Press Centre at the BA Festival of Science, visit www.the-ba.net/pressregister.
2. Diamond Light Source

 

• Diamond generates extremely intense pin-point beams of synchrotron light of exceptional quality ranging from x-rays, ultra-violet and infrared. For example Diamond’s x-rays are around 100 billion times brighter than a standard hospital X-ray machine or 10 billion times brighter than the sun.
• Many of our everyday commodities that we take for granted, from food manufacturing to cosmetics, from revolutionary drugs to surgical tools, from computers to mobile phones, have all been developed or improved using synchrotron light.
• Diamond Light Source Ltd. is a Joint Venture funded by the UK Government through the STFC (86%) and The Wellcome Trust (14%).
• Diamond will bring benefits to:

 

• Biology and medicine. For example, the fight against illnesses such as Parkinson's, Alzheimer's, osteoporosis and many cancers are benefiting from the new research techniques available at Diamond.
• The physical and chemical sciences. For example, in the near future, engineers will be able to image their structure down to an atomic scale, helping them to understand the way impurities and defects behave and how they can be controlled.
• The Environmental and Earth sciences. For example, Diamond helps researchers to identify organisms that target specific types of contaminant in the environment which can potentially lead to identifying cheap and effective ways for cleaning polluted land.

 

1. The BA (British Association for the Advancement of Science) is the UK's nationwide, open membership organisation that exists to advance the public understanding, accessibility and accountability of the sciences and engineering. Established in 1831, the BA organises major initiatives across the UK, including National Science and Engineering Week, the annual BA Festival of Science, programmes of regional and local events, and an extensive programme for young people in schools and colleges. The BA also organises specific activities for the science communication community in the UK through its Science in Society programme. For more information, please visit www.the-ba.net.
2. The University of Liverpool is a member of the Russell Group of leading research-intensive institutions in the UK. It attracts collaborative and contract research commissions from a wide range of national and international organisations valued at more than £108 million annually. For more information visit www.liv.ac.uk.
3. The Liverpool Culture Company was established by Liverpool City Council in 2000 to lead the city’s bid to be European Capital of Culture 2008. In June 2003, following a two-year nationwide competition featuring 12 cities, Liverpool was chosen as the UK’s representative for 2008. The programme for 2008 includes more than 350 events and festivals – many of which are free – delivered in collaboration with major cultural institutions, artists, performers and venues throughout Liverpool and beyond. For more information visit www.liverpool08.com.
4. The Northwest Regional Development Agency (NWDA) leads the economic development and regeneration of England's Northwest and is responsible for: supporting business growth and encouraging investment; matching skills provision to employer needs; creating the conditions for economic growth; connecting the region through effective transport and communication infrastructure; and promoting the region’s outstanding quality of life. For further information and to view previous press releases visit us at www.nwda.co.uk.
5. The life of Comet Wild-2
   On January 15th 2006 at 3 am a green fireball shot across the sky of West USA and its cause, a 1 m capsule, parachuted safely onto the Utah desert. This capsule had just completed a seven year, five billion km journey to Comet 81P/Wild 2 and back to Earth. The space mission is called Stardust, a mission to learn about the composition of comets. Comet Wild-2 (pronounced ‘Vilt 2’) has had a very long and very complicated life. It started in the earliest stages of the Solar System 4.56 billion years ago as the rocky, metallic and icy components that ultimately formed the planets started to condense. Comet Wild 2 passed close to Jupiter in 1974, causing it to be deflected into the inner Solar System – hence Wild-2 is classified as a Jupiter Family Comet. It now has an orbital period of 6 years with perihelion (nearest point to Sun) just beyond the distance of Mars and an aphelion (farthest point to Sun) near Jupiter’s orbit. In 1978 it was discovered by astronomer Paul Wild and this famous comet takes his name.

   Since Wild 2 hasn’t passed near to the Sun many times, it is in a relatively pristine condition with little sublimation of the ices and dust having taking place at this point in the comet’s life: ideal for the Stardust mission. After landing in Utah, the shell containing the collectors was quickly retrieved: landing in water or being rained on could have spelt ruin for the mission as the aerogel would have dissolved. Researchers at the University of Leicester are now studying Stardust grains at the university and at Diamond to not only find out what comets are made of but also to provide an insight into the provenance of the primitive meteorites that are held in collections which contain Fe oxides similar to those now identified in Comet Wild-2.

   To find out more about NASA’s Stardust mission visit http://stardust.jpl.nasa.gov/home/index.html