Andrew Yee
April 4th 06, 04:49 PM
ROYAL ASTRONOMICAL SOCIETY PRESS INFORMATION NOTE
Issued by RAS Communications Officers:
Peter Bond
Tel: +44 (0)1483-268672 Fax: +44 (0)1483-274047
AND
Anita Heward
Tel: +44 (0)1483-420904
NATIONAL ASTRONOMY MEETING PRESS ROOM (4 - 7 APRIL ONLY):
Tel: +44 (0)116-229-7474 or 229-7475 or 252-3312 or 252-3531
Fax: +44 (0)116-252-3531
RAS Web site:
http://www.ras.org.uk/
RAS National Astronomy Meeting web site:
http://www.nam2006.le.ac.uk/index.shtml
CONTACT DETAILS ARE LISTED AT THE END OF THIS RELEASE.
EMBARGOED FOR 00:01 BST, TUESDAY, 4 APRIL 2006 (23:01 GMT ON MONDAY
3 APRIL)
Ref.: PN 06/15 (NAM 8)
SLEW SURVEY REVEALS SECRETS OF X-RAY SKY
The European Space Agency's XMM-Newton X-ray observatory has
already been a spectacular success in many areas of astronomy --
detecting distant clusters of galaxies, the faint afterglow of
enigmatic gamma ray bursts and the effects of the collision of
the Deep Impact probe with comet Tempel-1.
Now an innovative new approach analyses X-rays detected during
the times that the satellite manoeuvres between targets -- originally
considered to be unusable periods -- to reveal some 4,000 intensely
brilliant X-ray stars and galaxies.
An initial study has identified these with a host of highly
energetic celestial phenomena. These include close binary stars,
where matter is being pulled away from one star to explode onto
the surface of the companion; and distant quasars, super-luminous
galaxies up to 10 billion light years from Earth, which are being
slowly consumed by a voracious central black hole.
Preliminary results from this study, known as the XMM-Newton Slew
Survey, will be presented today (Tuesday) at the RAS National
Astronomy Meeting in Leicester by Dr. Andy Read of Leicester
University.
XMM-Newton, with the huge collecting area of its many nested
mirrors and the excellent efficiency of its EPIC X-ray
camera/detector, is the most sensitive X-ray observatory ever
flown. As a result, it is able to record unrivalled numbers of
X-rays from the cosmos.
Since its launch in December 1999, XMM-Newton has observed thousands
of objects, gazing at a particular X-ray source for hours, before
turning or 'slewing' away at a great speed to observe its next
target. Since September 2001, the XMM-Newton 'shutter' has been
open during these slews, and this has yielded hundreds of extremely
long snapshot strips of the X-ray sky.
Though the slews are so quick that XMM-Newton passes over each
point in the sky in only 10 seconds (compared to a normal 'pointed'
observation of a few hours), this 10 second exposure is enough
time for XMM-Newton to detect thousands of sources in the sky.
"The area of the sky that is covered is enormous," said Andy Read.
"Over a quarter of the entire sky has already been covered in
the 400 or so slews so far performed, and many more slews are
continually taking place.
"The entire sky will be covered -- even at the present extremely
slow rate -- over the lifetime of the XMM-Newton mission.
"As such, this XMM-Newton slew survey, even coming as it does, for
'free', rivals the best of all previous dedicated all-sky X-ray
surveys. For detecting high-energy X-rays, it is certainly the
best that there has ever been.
"A wonderful variety of X-ray sources has been seen in the Slew
Survey, including black holes, quasars, active galaxies and
stars -- many of which have been observed for the first time."
Only a survey such as this, covering such a large area of the sky,
is able to observe the rarest of events. The team involved in the
survey has, for example, seen a number of X-ray sources undergoing
extraordinary changes in brightness, events that are thought to
be due to stars being captured whole by massive black holes.
The best example is an otherwise normal galaxy, about 40 million
light years away, which has been seen to increase remarkably in
X-ray brightness (possibly linked to matter being drawn into a
supermassive central black hole).
"This galaxy is far, far brighter than it was when previously
observed with older X-ray satellites," said Dr. Read.
Furthermore, the great sensitivity and low 'noise' of the EPIC
CCD camera is especially suited to detect emission from extended
sources that cover a large area of space, and many extremely
interesting supernova remnants and massive clusters of galaxies
have been observed.
"Multi-slews that are criss-crossing large areas of the sky are
now giving us new, large-scale views of the biggest X-ray objects
in the sky," said Andy Read.
CONTACT:
Dr. Andy Read
Dept. of Physics and Astronomy
University of Leicester
Leicester LE1 7RH
Tel: +44 (0)116-252-5650
From 4 to 7 April, Dr. Read can be contacted via the NAM press
office (see above).
NOTES FOR EDITORS
Other members of the XMM-Newton Slew Survey team are: Richard
Saxton (ESAC, Spain); Pili Esquej (MPE, Germany / ESAC, Spain);
Dr. Michael Freyberg (MPE, Germany); and Dr. Bruno Altieri
(ESAC, Spain).
The European Photon Imaging Camera (EPIC) was developed by a
consortium led by the University of Leicester, UK.
The 2006 RAS National Astronomy Meeting is hosted by the University
of Leicester. It is sponsored by the Royal Astronomical Society,
the UK Particle Physics and Astronomy Research Council (PPARC),
the University of Leicester and the National Space Centre,
Leicester.
IMAGES:
Examples of images from the XMM-Newton Slew Survey can be found at:
http://www.star.le.ac.uk/~amr30/Slew/
Issued by RAS Communications Officers:
Peter Bond
Tel: +44 (0)1483-268672 Fax: +44 (0)1483-274047
AND
Anita Heward
Tel: +44 (0)1483-420904
NATIONAL ASTRONOMY MEETING PRESS ROOM (4 - 7 APRIL ONLY):
Tel: +44 (0)116-229-7474 or 229-7475 or 252-3312 or 252-3531
Fax: +44 (0)116-252-3531
RAS Web site:
http://www.ras.org.uk/
RAS National Astronomy Meeting web site:
http://www.nam2006.le.ac.uk/index.shtml
CONTACT DETAILS ARE LISTED AT THE END OF THIS RELEASE.
EMBARGOED FOR 00:01 BST, TUESDAY, 4 APRIL 2006 (23:01 GMT ON MONDAY
3 APRIL)
Ref.: PN 06/15 (NAM 8)
SLEW SURVEY REVEALS SECRETS OF X-RAY SKY
The European Space Agency's XMM-Newton X-ray observatory has
already been a spectacular success in many areas of astronomy --
detecting distant clusters of galaxies, the faint afterglow of
enigmatic gamma ray bursts and the effects of the collision of
the Deep Impact probe with comet Tempel-1.
Now an innovative new approach analyses X-rays detected during
the times that the satellite manoeuvres between targets -- originally
considered to be unusable periods -- to reveal some 4,000 intensely
brilliant X-ray stars and galaxies.
An initial study has identified these with a host of highly
energetic celestial phenomena. These include close binary stars,
where matter is being pulled away from one star to explode onto
the surface of the companion; and distant quasars, super-luminous
galaxies up to 10 billion light years from Earth, which are being
slowly consumed by a voracious central black hole.
Preliminary results from this study, known as the XMM-Newton Slew
Survey, will be presented today (Tuesday) at the RAS National
Astronomy Meeting in Leicester by Dr. Andy Read of Leicester
University.
XMM-Newton, with the huge collecting area of its many nested
mirrors and the excellent efficiency of its EPIC X-ray
camera/detector, is the most sensitive X-ray observatory ever
flown. As a result, it is able to record unrivalled numbers of
X-rays from the cosmos.
Since its launch in December 1999, XMM-Newton has observed thousands
of objects, gazing at a particular X-ray source for hours, before
turning or 'slewing' away at a great speed to observe its next
target. Since September 2001, the XMM-Newton 'shutter' has been
open during these slews, and this has yielded hundreds of extremely
long snapshot strips of the X-ray sky.
Though the slews are so quick that XMM-Newton passes over each
point in the sky in only 10 seconds (compared to a normal 'pointed'
observation of a few hours), this 10 second exposure is enough
time for XMM-Newton to detect thousands of sources in the sky.
"The area of the sky that is covered is enormous," said Andy Read.
"Over a quarter of the entire sky has already been covered in
the 400 or so slews so far performed, and many more slews are
continually taking place.
"The entire sky will be covered -- even at the present extremely
slow rate -- over the lifetime of the XMM-Newton mission.
"As such, this XMM-Newton slew survey, even coming as it does, for
'free', rivals the best of all previous dedicated all-sky X-ray
surveys. For detecting high-energy X-rays, it is certainly the
best that there has ever been.
"A wonderful variety of X-ray sources has been seen in the Slew
Survey, including black holes, quasars, active galaxies and
stars -- many of which have been observed for the first time."
Only a survey such as this, covering such a large area of the sky,
is able to observe the rarest of events. The team involved in the
survey has, for example, seen a number of X-ray sources undergoing
extraordinary changes in brightness, events that are thought to
be due to stars being captured whole by massive black holes.
The best example is an otherwise normal galaxy, about 40 million
light years away, which has been seen to increase remarkably in
X-ray brightness (possibly linked to matter being drawn into a
supermassive central black hole).
"This galaxy is far, far brighter than it was when previously
observed with older X-ray satellites," said Dr. Read.
Furthermore, the great sensitivity and low 'noise' of the EPIC
CCD camera is especially suited to detect emission from extended
sources that cover a large area of space, and many extremely
interesting supernova remnants and massive clusters of galaxies
have been observed.
"Multi-slews that are criss-crossing large areas of the sky are
now giving us new, large-scale views of the biggest X-ray objects
in the sky," said Andy Read.
CONTACT:
Dr. Andy Read
Dept. of Physics and Astronomy
University of Leicester
Leicester LE1 7RH
Tel: +44 (0)116-252-5650
From 4 to 7 April, Dr. Read can be contacted via the NAM press
office (see above).
NOTES FOR EDITORS
Other members of the XMM-Newton Slew Survey team are: Richard
Saxton (ESAC, Spain); Pili Esquej (MPE, Germany / ESAC, Spain);
Dr. Michael Freyberg (MPE, Germany); and Dr. Bruno Altieri
(ESAC, Spain).
The European Photon Imaging Camera (EPIC) was developed by a
consortium led by the University of Leicester, UK.
The 2006 RAS National Astronomy Meeting is hosted by the University
of Leicester. It is sponsored by the Royal Astronomical Society,
the UK Particle Physics and Astronomy Research Council (PPARC),
the University of Leicester and the National Space Centre,
Leicester.
IMAGES:
Examples of images from the XMM-Newton Slew Survey can be found at:
http://www.star.le.ac.uk/~amr30/Slew/