Andrew Yee[_1_]
May 8th 08, 08:36 PM
ROYAL ASTRONOMICAL SOCIETY PRESS INFORMATION NOTE
Issued by RAS Press Officers:
Dr Robert Massey
Tel: +44 (0)20 7734 3307 / 4582
Anita Heward
Tel: +44 (0)1483 420904
NATIONAL ASTRONOMY MEETING PRESS ROOM (31 MARCH - 4 APRIL ONLY):
Tel: +44 (0)2890 975262 / 975263 / 975264
NAM 2008
http://nam2008.qub.ac.uk
Royal Astronomical Society
http://www.ras.org.uk
CONTACTS
Dr Emma Whelan
School of Cosmic Physics
Dublin Institute for Advanced Studies
31 Fitzwilliam Place
Dublin 2
IRELAND
E-mail: ewhelan at cp.dias.ie
Professor Tom Ray
School of Cosmic Physics
Dublin Institute for Advanced Studies
31 Fitzwilliam Place
Dublin 2
IRELAND
E-mail: tr at cp.dias.ie
EMBARGOED UNTIL 0001 BST, 1 April 2008
Ref.: PN 08/35 (NAM 26)
Newborn brown dwarfs stir up the neighbourhood
Scientists working at the Dublin Institute for Advanced Studies have found a
clutch of jets from newborn brown dwarfs. In her talk on Tuesday 1 April at
the RAS National Astronomy Meeting in Belfast, postdoctoral researcher Dr
Emma Whelan will announce the discovery of more jets from these intriguing
objects, bringing the total to 4.
New stars form in cold clouds of gas and dust. These so-called stellar
nurseries are not only home to forming stars (protostars) but also harbour
forming brown dwarfs. These are objects with masses between 13 and 75 times
the mass of the gas giant planet Jupiter and bridge the gap between stars
and planets. Brown dwarfs are often described as "failed stars", simply
because they never become massive enough for nuclear fusion reactions to
take place in their cores (in normal stars like the Sun energy is released
as hydrogen is fused to make helium).
Young brown dwarfs are more "star-like" than their status as "failed stars"
suggests. In particular, the Dublin scientists have found that they drive
outflows like those from protostars and the pace of discovery implies that
these are common.
Astronomers have long asked whether brown dwarfs form like stars or like
planets. A star like the Sun originates through the gravitational collapse
of a 'clump' of material. As the collapse proceeds, a protostar forms at the
centre of a disk of dust and gas with the star-disk system surrounded by a
halo of infalling matter. Because the central star and disk are rotating,
some of the infalling material is thrown out of the system as an outflow or
jet.
Dr Whelan comments, "The new discoveries mean that jets are confirmed to
flow from a huge range of objects, from tiny brown dwarfs to the largest
black holes with masses of billions of Suns found at the heart of some
galaxies. This leads us to the tantalising prospect that even large planets
may drive outflows and jets as they form."
FURTHER INFORMATION
* Dublin Institute for Advanced Studies -- Emma Whelan
http://www.dias.ie/~ewhelan/Site/Emma_Whelan.html
Issued by RAS Press Officers:
Dr Robert Massey
Tel: +44 (0)20 7734 3307 / 4582
Anita Heward
Tel: +44 (0)1483 420904
NATIONAL ASTRONOMY MEETING PRESS ROOM (31 MARCH - 4 APRIL ONLY):
Tel: +44 (0)2890 975262 / 975263 / 975264
NAM 2008
http://nam2008.qub.ac.uk
Royal Astronomical Society
http://www.ras.org.uk
CONTACTS
Dr Emma Whelan
School of Cosmic Physics
Dublin Institute for Advanced Studies
31 Fitzwilliam Place
Dublin 2
IRELAND
E-mail: ewhelan at cp.dias.ie
Professor Tom Ray
School of Cosmic Physics
Dublin Institute for Advanced Studies
31 Fitzwilliam Place
Dublin 2
IRELAND
E-mail: tr at cp.dias.ie
EMBARGOED UNTIL 0001 BST, 1 April 2008
Ref.: PN 08/35 (NAM 26)
Newborn brown dwarfs stir up the neighbourhood
Scientists working at the Dublin Institute for Advanced Studies have found a
clutch of jets from newborn brown dwarfs. In her talk on Tuesday 1 April at
the RAS National Astronomy Meeting in Belfast, postdoctoral researcher Dr
Emma Whelan will announce the discovery of more jets from these intriguing
objects, bringing the total to 4.
New stars form in cold clouds of gas and dust. These so-called stellar
nurseries are not only home to forming stars (protostars) but also harbour
forming brown dwarfs. These are objects with masses between 13 and 75 times
the mass of the gas giant planet Jupiter and bridge the gap between stars
and planets. Brown dwarfs are often described as "failed stars", simply
because they never become massive enough for nuclear fusion reactions to
take place in their cores (in normal stars like the Sun energy is released
as hydrogen is fused to make helium).
Young brown dwarfs are more "star-like" than their status as "failed stars"
suggests. In particular, the Dublin scientists have found that they drive
outflows like those from protostars and the pace of discovery implies that
these are common.
Astronomers have long asked whether brown dwarfs form like stars or like
planets. A star like the Sun originates through the gravitational collapse
of a 'clump' of material. As the collapse proceeds, a protostar forms at the
centre of a disk of dust and gas with the star-disk system surrounded by a
halo of infalling matter. Because the central star and disk are rotating,
some of the infalling material is thrown out of the system as an outflow or
jet.
Dr Whelan comments, "The new discoveries mean that jets are confirmed to
flow from a huge range of objects, from tiny brown dwarfs to the largest
black holes with masses of billions of Suns found at the heart of some
galaxies. This leads us to the tantalising prospect that even large planets
may drive outflows and jets as they form."
FURTHER INFORMATION
* Dublin Institute for Advanced Studies -- Emma Whelan
http://www.dias.ie/~ewhelan/Site/Emma_Whelan.html