| Article: 388
From: [email protected] (Ron Baalke)
Newsgroups: sci.space.news
Subject: IRAS CD-ROMs Now Available
Date: 26 Feb 92 05:19:16 GMT
Sender: [email protected] (Usenet)
Organization: Jet Propulsion Laboratory
====================
IRAS CD-ROMs
February 25, 1992
====================
The first release of the IRAS Sky Survey Atlas is now available to the
public on four CD-ROMs. The Infrared Astronomical Satellite (IRAS) was
launched in 1983 into low Earth orbit to scan the entire sky in search of
infrared radiation from galaxies, dust clouds, stars, solar system objects,
and previously unknown objects. From January to November 1983, IRAS conducted
a survey of 98% of the sky in four wavelengths centered at 12, 25, 60 and
100 microns. IRAS was a joint mission between JPL, the United Kingdom and
the Netherlands.
The four CD-ROMs in this release covers the high ecliptic latitudes
from 50 to 90 degrees and from -50 to -90 degrees, which comprises 38% of the
sky. The images on these CD-ROMs are 500x500 pixel resolution FITS images,
and consists of 16 bit and 32 bit images. The images have been processed by
the Infrared Processing and Analysis Center (IPAC) at Caltech/JPL to improve
the calibration and to remove zodiacal emission. The second set of CD-ROMs of
the IRAS Sky Survey which will cover the entire sky will be released later
this year.
The IRAS CD-ROMs along with display software can be obtained from the
National Space Science Data Center (NSSDC) for a small fee of $38. You can
contact NSSDC at:
National Space Science Data Center
Goddard Space Flight Center
Greenbelt, Maryland 20771
Telephone: (301) 286-6695
Email address: [email protected]
___ _____ ___
/_ /| /____/ \ /_ /| Ron Baalke | [email protected]
| | | | __ \ /| | | | Jet Propulsion Lab |
___| | | | |__) |/ | | |__ M/S 525-3684 Telos | In the middle of difficulty
/___| | | | ___/ | |/__ /| Pasadena, CA 91109 | lies opportunity --
|_____|/ |_|/ |_____|/ | Albert Einstein
|
| From: DECWRL::"[email protected]" "Ron Baalke" 30-JAN-1993
To: [email protected]
CC:
Subj: IRAS - 10 Years Ago
From the "JPL Universe"
January 29, 1993
IRAS: 10 years ago, infrared widened our eyes
By Mary Hardin
Ten years ago this week, the launch of the Infrared
Astronomical Satellite (IRAS) made history as the first
spacecraft designed specifically to study the universe at
infrared wavelengths.
"IRAS opened the entire Milky Way to our view, revealing
previously unsuspected phenomena and providing new probes of the
structure of the galaxy," said Dr. Charles Beichman, director of
JPL's Infrared Processing and Analysis Center (IPAC) and a member
of the IRAS science team.
The satellite was an international project involving The
Netherlands, the United Kingdom and the United States, but its
early life was so full of problems it almost didn't get off the
ground. To begin with, the project was two years and tens of
millions of dollars over budget due to problems with the
detectors, the telescope and the cryogenic valves. There were
also some fears that the cover would not come off the telescope,
and if it did, that the mirror would be covered with nitrogen
frost. Despite these concerns, the spacecraft was launched, and
after a troubled start, it began producing a steady stream of data.
To ensure that the satellite was sensitive to the infrared
heat coming from deep space, the spacecraft carried 700 liters of
superfluid helium to cool the telescope and detectors to a
temperature of 2 degrees Celsius above absolute zero. After 10
months in orbit, the helium evaporated and the data-taking
portion of the mission was over.
But the data-analysis phase was just beginning. From its
vantage point above the glare of Earth's atmosphere, IRAS
produced more than 600,000 individual objects and more than 1,600
images of the entire sky. All told, the IRAS mission has helped
astronomers make many startling discoveries.
"IRAS found more evidence for planet building among mature
stars," Beichman said. "One of the great surprises of the mission
was that Vega, one of the brightest visible stars in the sky, was
10 times brighter in the infrared than predicted. The infrared
radiation coming from Vega, and similar stars, is consistent with
a ring or disk of solid material orbiting the central star. IRAS
found that one-quarter of all stars have this same phenomenon."
Another surprise was the number of galaxies it revealed. "No
one expected IRAS to find more than 1,000 galaxies, but we found
60,000," Beichman exclaimed. "These galaxies have been used to
probe the overall structure of the universe. One IRAS object may
be a galaxy captured in the process of formation.
"IRAS was also a prolific comet finder, having detected
about 25 of them," he continued.
Observations of these objects have changed the way
scientists think about comets. Prior to IRAS, astronomers thought
comets were large balls of ice hurtling through space. IRAS
showed that comets are made of mostly dirt and rock, with an icy
covering.
The wealth of data produced by IRAS is used in ongoing
research by astronomers from around the world.
"IRAS revealed the infrared sky to us in the way people will
be looking at it for a long time," Beichman said. "It is our
first and only view of what's out there until somebody does it
better. And it's not going to be easy to do it much better than
we did."
That opportunity to follow up on many of the IRAS
discoveries will come sometime after the turn of the century,
when JPL's Space Infrared Telescope Facility (SIRTF) is launched
into solar orbit. SIRTF will take advantage of the enormous
technical advances in infrared detector arrays that have been
made over the last decade, making it 1,000 times more sensitive
than IRAS.
However, SIRTF may lack a bit of magic that came with its
predecessor. "After all, one can open one's eyes to the night sky
for the first time only once," Beichman concluded. That honor
will forever belong to IRAS.
___ _____ ___
/_ /| /____/ \ /_ /| Ron Baalke | [email protected]
| | | | __ \ /| | | | Jet Propulsion Lab |
___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Every once in a while,
/___| | | | ___/ | |/__ /| Pasadena, CA 91109 | try pushing your luck.
|_____|/ |_|/ |_____|/ |
% ====== Internet headers and postmarks (see DECWRL::GATEWAY.DOC) ======
% From: [email protected] (Ron Baalke)
% Subject: IRAS - 10 Years Ago
|
| From: US2RMC::"[email protected]" "MAIL-11 Daemon" 6-JUL-1994
To: [email protected]
CC:
Subj: Cosmic Dust Ring Detected
Cosmic dust may explain life on earth
6/30/94
GAINESVILLE, Fla., June 30 (UPI) -- A ring of cosmic dust around
the sun may have supplied the carbon essential to the beginning of
life, University of Florida scientists said Thursday.
Stanley F. Dermott, professor and chairman of the university's
astronomy department, said discovery of the dust, which originates in
the asteroid belt, may help to unravel some mysteries on the origin of
life.
"This dust is largely carbonaceous material -- the material from
which life could form," Dermott reported in a June 30 cover story in
the British journal Nature. "This ring may act as a kind of funnel and
may have been the means of getting this life-forming material onto the
Earth after the planet formed."
Asteroids collide to form dust that collects in a gigantic ring
around the sun. The Earth's orbit is inside the ring, and the Earth's
gravity may pull much of the dust into the atmosphere and onto the
planet's surface, added Dermott, who is working to confirm this part
of the theory.
"The ring's existence will come as a surprise to astronomers,"
Dermott said. "Nothing like this has been found before -- that the
planets themselves are in rings that extend around the sun."
The cloud's existence was confirmed by observations from NASA's
Infrared Astronomical Satellite and computer experiments at UF, said
Dermott, who did the research with graduate student Sumita Jayaraman.
Dermott said he became suspicious when NASA's infrared, or heat-
sensitive, satellite detected heat from the dust. Seven years ago, he
said, he and Philip Nicholson of Cornell University discovered that
the half of the sky behind the Earth in its orbit was consistently
brighter than the other half, not realizing then that the cause was
the dust cloud trailing the Earth.
According to Dermott, one other development is the potential for
astronomers to study asteroidal material in their own back yard.
"People think of getting a sample of extra-terrestrial body off a
spacecraft. We now realize that bits of these particles collide with
the Earth and can be collected here for scientific study," he said.
The ring's discovery gives scientists a new way of thinking about
age-old questions, said Dermott. "Now that we've found this ring, we
can start to work on its implications for the mysteries of the origin
of life."
(Written by Jeff Bray in Miami, Edited by Larry Schuster, UPI
Science and Technology Editor in Washington)
% ====== Internet headers and postmarks (see DECWRL::GATEWAY.DOC) ======
% Date: Tue, 5 Jul 1994 17:58:05 GMT
% From: Ron Baalke <[email protected]>
% To: [email protected]
% Message-Id: <[email protected]>
% Subject: Cosmic Dust Ring Detected
% Sender: [email protected]
% Reply-To: [email protected]
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