Leiden PhD researcher wins NASA Hubble Fellowship
Leiden PhD researcher Karin Öberg is one of the 17 winners of the NASA Hubble Fellowship. When she has obtained her PhD this autumn she will move to the United States for three years to conduct post-doctoral research into the role of ice in star formation.
Origin of the universe
The NASA Hubble Fellowship is awarded annually to a select group of young astronomers who contribute to scientific knowledge about the origin of the universe. All fellowship winners conduct independent research related to NASA's Cosmic Origins Programme. Together they share a fascination for the history of the origin of the cosmos.
Beautiful pictures
For Karin Öberg, this fascination started very early. She was given her first astronomy book when she was just seven: 'It was a present from my father. I thought the pictures in the book were beautiful, and I was immediately hooked.' Now, almost twenty years later, Öberg has become an astronomer and is herself carrying out pioneering research in the field. She couldn't have been happier when she received a telephone call from Dr Ron Allen, chairman of the Hubble Fellowship Programme. ‘I'd wanted this award for such a long time,' she says. 'It's just wonderful to have got it.'
Ice formation
Öberg studies chemical processes which precede the formation of stars and planets. Ice plays an important role. 'New stars and planets are formed in cold gas nebula,' Öberg explains. ‘The tiny dust particles in these gas clouds are so cold that gases precipitate on them and form a layer of ice. Not only ice from water, but also ice from other molecules such as carbon monoxide and carbon dioxide. This ice is then broken down by energy-rich UV light from newly formed stars. The fragments togethyer form new, more complex molecules.' So there are chemical processes continuously taking place in the cold gas clouds of the universe. These processes determine the chemical evolution of the universe and are eventually important for the origin of life, in Öberg's opinion.
Laboratory simulations
Ron Allen from the Hubble Fellowship Programme was particularly impressed by the inventive way in which she combines astronomy with chemistry, Öberg explains. She and her Leiden colleagues not only make use of the latest telescope observations, but also of small scale chemical simulations. In the Raymond & Beverly Sackler Laboratory for Astrophysics at the Leiden Observatory, the researchers simulated what happens in the nurseries of the universe. They use an area under vacuum into which they pump minuscule amounts of gas. As a result of the extremely low temperature (-263 degrees Celsius, 10 degrees above absolute zero) the gases freeze onto a plate. The researchers irradiate the plate with UV light, which initiates chemical processes which result in new substances. 'By studying these processes on the earth, we gain a better understanding of what happens in huge cosmic gas clouds,' says Öberg.
Chemical evolution
After obtaining her PhD, Öberg will exchange the Leiden Observatory for the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, where she will research increasingly complex processes in the chemical evolution of ice. She will maintain contacts with her Leiden colleagues. Her supervisors, Professor Ewine van Dishoeck and Professor Harold Linnartz, are active at the forefront of molecular astrophysics, as the field is known.
History
Öberg studied from 2001 to 2005 in the US, at the California Institute of Technology and is looking forward to her reunion with the country. 'I like the American ethic that you can go a long way if you do your best.' A pleasant coincidence for Öberg is that she can also enjoy her other passion of history at the Cambridge university campus. 'I am interested in the origin of things,' she says. 'In that respect, astronomy and history are similar sciences. As an astronomer I am in fact always looking to the past.'
(3 March 2009/Tristan Lavender)