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25-Feb-93 Daily File Collection
These files were added or updated between 24-Feb-93 at 21:00:00 {Central}
and 25-Feb-93 at 21:00:14.
=--=--=START=--=--= NASA Spacelink File Name:930225.REL
2/25/93: SUPERNOVA MAY HAVE CAUSED HUGE VOID AROUND SOLAR SYSTEM
Michael Braukus
Headquarters, Washington, D.C. February 25, 1993
Michael Finneran
Goddard Space Flight Center, Greenbelt, Md.
RELEASE: 93-036
A supernova that shone in the ancient sky like a second moon
is the probable cause of a huge void known as the "Local Bubble"
that envelopes the solar system and many nearby stars, a NASA
scientist reported in today's issue of the British journal
"Nature."
The bubble is an area about 300 light-years across that,
compared to other parts of space, is relatively empty of gases
except for super-hot hydrogen. The bubble's origin has been the
subject of intense speculation for the last 20 years.
Now, researchers at NASA's Goddard Space Flight Center,
Greenbelt, Md., say evidence suggests it was formed by the
supernova or explosion of a star known as Geminga about 340,000
years ago.
"This is a supernova we didn't know about until last year.
We put this new knowledge together with some other information
about the Local Bubble, and we were able to say we think we know
what happened here," said Dr. Neil Gehrels, of Goddard. Gehrels
wrote the paper with Dr. Wan Chen, of Universities Space Research
Association.
A supernova is an internal explosion that blows away a
star's outer layers, leaving a dense, collapsed, rapidly spinning
core that emits energy in pulses. Stars that have undergone a
supernova are known as pulsars. The Local Bubble would have been
formed by the force of the supernova blasting most of the gases
out of the surrounding interstellar medium, according to the
authors.
"This must have been the brightest supernova ever seen by
Homo sapiens," said Gehrels. "Everybody would have immediately
noticed it. It would have been quite a spectacular and
frightening event, though not one that would have threatened the
planet's existence."
Supernovas always create such bubbles, Gehrels said.
Similar bubbles, including a cluster of several around the Local
Bubble, probably were formed around our solar system millions of
years ago by supernovas just as close as Geminga. But those
would have collapsed and dissipated by now, leaving little or no
trace of their existence, he said.
Astrophysicists have long speculated that the current Local
Bubble was created by a supernova. But for that to have
happened, the star would had to have been relatively nearby.
Until recently, the evidence for that was scant, said Gehrels.
In the last year, however, several discoveries have given
weight to the theory. Scientists at Goddard and Columbia
University in New York City determined that Geminga is a pulsar
and therefore had to have undergone a supernova at some point.
That finding was made using x-ray data from the Roentgen
Satellite and was confirmed by NASA's Compton Gamma Ray
Observatory.
From Geminga's pulsations, scientists calculated that the
star is no more than 340,000 years old and was about 180 light
years away -- close enough to have created the bubble -- when the
supernova occurred. The authors estimate Geminga has since moved
to about 400 light-years away.
Further evidence recently presented by a team of Italian
astronomers helped Gehrels and Chen place Geminga more precisely.
Calculations based on its speed suggested the star was born in a
position to have created the bubble. The Italian team also
reported that the swiftness with which Geminga crosses the sky
indicates it is not far away.
"So we now know the position for this nearby supernova,"
Gehrels said. "It is right near the current middle of the Local
Bubble."
Gehrels said the supernova that created the bubble would
have been a unique experience for anyone on Earth who witnessed
it.
According to Gehrels, observers would have seen the sudden
appearance of a star emitting as much light as the moon, visible
even in daylight. With a full moon in the sky, the nights would
have been twice as bright as usual. Geminga would have lingered
like a beacon for several months before fading. Currently, it
cannot be seen with the naked eye.
At the time of the supernova, intense x-rays and gamma rays
from the explosion likely would have depleted the Earth's ozone
layer by 10 to 20 percent globally, Gehrels said in remarks not
included in the "Nature" paper. The resulting increase in
ultraviolet radiation, he said, would have been small enough not
to disrupt life on Earth but may have been noticed by early
humans.
"Whomever was here back then would have experienced a
sunburn for a year or two," Gehrels said. "One can only wonder
if anybody at that time figured out that Geminga was the cause."
Source:NASA Spacelink Modem:205-895-0028 Internet:192.149.89.61
=--=--=-END-=--=--=
=--=--=START=--=--= NASA Spacelink File Name:930225.SHU
KSC SHUTTLE STATUS 2/25/93
SPACE SHUTTLE DAILY STATUS-STS 55
Thursday, February 25, 1993
George H. Diller
Kennedy Space Center
Vehicle: OV-102/Orbiter Columbia Mission: STS-55
Current location: Pad 39-A Orbital altitude: 184 sm
Payload: Spacelab D-2 Inclination: 28.45 degrees
Launch timeframe: March wk 2 Nominal Landing: KSC
Mission Duration: 8 days 22 hours Crew size: 7
STS-55 IN WORK:
- conclusion of high pressure turbopump connections and securing
- troubleshooting enhanced orbiter refrigerator/freezer unit
- GAS can experiment removal preparations
- hydraulic fluid particle sampling
STS-55 WORK SCHEDULED:
- final turbopump leak checks on Friday
- remove GAS experiments on Friday for battery charging
- reinstall GAUS film magazine Saturday
- Flight Readiness Test of main engines/aerosurfaces
- install main engine heat shields
- load orbiter mass memory units
- Helium Signature leak checks
STS-55 WORK COMPLETED:
- potable water microbial sampling
- removal of GAUS experiment film magazine for servicing
Source:NASA Spacelink Modem:205-895-0028 Internet:192.149.89.61
=--=--=-END-=--=--=
=--=--=START=--=--= NASA Spacelink File Name:930225.SKD
DAILY NEWS/TV SKED 2-25-93
NASA Daily News
Thursday, Feb. 25, 1993
Audio Svc. 202-358-3014
New findings on the El Nino ocean current will be among topics
discussed at a press conference on the TOPEX/Poseidon satellite
mission tomorrow, Friday, Feb. 26, at 1 p.m. EST, in the von Karman
Auditorium at the Jet Propulsion Laboratory. Scientists will discuss
initial results from the U.S./French TOPEX/Poseidon satellite, which
was launched August 10, 1992 to map circulation of the world's
oceans and study the ocean's role in climate. The press conference
comes at the end of a week-long conference attended by more than
150 TOPEX/Poseidon scientists and oceanographers from around the
world.
Participants will included Charles Yamarone Jr., Poject Manager; Dr.
Lee-Lueng Fu, JPL Project Scientist; Dr. William Patzert, NASA
Program Scientist; Michel Dorrer, French Project Manager; Michel
Lefebvre, French Project Scientist; Jean-Francois Minister of the
Centre National d'Etudes Spatiales, Toulouse France; and James
Mitchell of the Naval Oceanographic and Atmospheric Rsearch
Laboratory in Mississippi. They will present results of the mission's
verification phase, including the first map of ocean topography and
a video animation of the global ocean current systems mapped by
TOPEX/Poseidon. The press conference will be broadcast live on
NASA Select.
Today's update from the Kenndy Space Center on the progress of
preparing Columbia for the STS-55 mission, reports that a launch
date is expected to be set tommorrow, Friday, Feb. 26. Work
scheduled on the mission includes removal of GAS experiments
tomorrow, and reinstallation of the GAUS film magazine on
Saturday. On Sunday, workers will begin installation of main
engines heat shields and then on Monday will load orbiter mass
memory units.
Marshall Space Flight Center reports that its popular Space Station
Freedom trailers and a 1:15 scale Space Shuttle model were set up
next to the Alabama Capitol on February 16 and 17 in support of a
Huntsville Chamber of Commerce-sponsored visit to Montgomery.
Approximately 3,000 people, including 13 state legislators visited
the exhibit.
Here is the broadcast schedule for Public Affairs events on NASA
Select TV. Note that all events and times may chnage without
notice, and that all times listed are Eastern. Live indicates a program
is transmitted live.
Thursday, February 25, 1993
12:00pm NASA Today news program (live)
12:15 pm Aeronautics & Space Report
12:30 pm Best of NASA Today; NASAA Visitor Centers
1:00pm One Step Closer
1:30 pm Zero-G and Space Suits
2:00 pm Starfinder #6
2:30 pm Examination of Life
3:00 pm TQM #44
NASA Select TV is carried on GE Satcom F2R, transponder 13, C-Band, 72 degrees
West Longitude, transponder frequency is 3960 MegaHertz, audio subcarrier is
6.8 MHz, polarization is vertical.
Source:NASA Spacelink Modem:205-895-0028 Internet:192.149.89.61
=--=--=-END-=--=--=
=--=--=START=--=--= NASA Spacelink File Name:930225A.REL
2/25/93: NASA FUNDS EXPERIMENT TO HELP COMMERCIALIZE TECHNOLOGY
Charles Redmond
Headquarters, Washington, D.C. February 25, 1993
RELEASE: 93-037
Beginning this month NASA's latest experiment will test
"technology incubation" -- a new laboratory-to-market approach
designed to help space technology contribute to U.S. industrial
competitiveness.
NASAUs Office of Advanced Concepts and Technology began the
3-year technology commercialization experiment by funding two
Technology Commercialization Centers, one at the its Ames Research
Center, Mountain View, Calif., and the other at Johnson Space
Center, Houston. The program, funded this year for $800,000, is
being managed and will be operated by the IC2 Institute at the
University of Texas, Austin.
The two NASA technology commercialization centers will be set
up by the IC2 Institute's staff and will draw upon a regional
network of entrepreneurs, investment capital, market and business
savvy on the one hand and the NASA field center talent and
technology pool on the other.
The two NASA centers were selected as test case areas because
of the variety of technologies being developed at each center and
the existing economic and business infrastructure to support those
technologies in the two locales.
The IC2 Institute was selected by NASA because of its
successful work with University of Texas (UT) technology spinoffs.
The institute operates the Austin Technology Incubator, which has
worked with the University and economic partners in the Austin
area during the last few years to create new companies and jobs
from research work performed at UT.
The IC2 Institute has developed a laboratory-to-market model
which specializes in technology incubation P taking the
technological output of a laboratory, in this case JSC and Ames,
and pairing that technology with appropriate partners in the
business and financial community to create and foster new industry
and with the industry, new jobs.
The IC2 will work during the 3-year grant period to forge
firm links between the two NASA centers and community and economic
resources in the Bay Area and in Southeastern Texas. The goal of
this project is to accelerate the technology commercialization
process and to bolster the entrepreneurial spirit throughout NASA.
Both Ames and JSC will have separately-operated "incubators," with
staff provided by the IC2 Institute.
The NASA goal is to shorten the learning curve associated
with successfully commercializing technology from NASA to the
private sector and to reduce the time required for this transfer
to take place. IC2 will be working directly with individuals at
both centers to foster financial support and community resources
which might be required to bring a NASA-developed technology to
the commercial market.
In Houston much of the expected technology commercialization
will involve medical science and aerospace research because of
JSC's role as the manned space center and because of the Houston
areaUs position as a world-leader in medical technology and the
emerging role of Houston in the aerospace field. For Ames the
focus is expected to be computing skills and hardware, materials
and selected medical areas and the capabilities of the Silicon
Valley to support and commercialize that type of technology.
The two centers represent dramatically different types of
technology development and reside in strongly different economic
and social regions. As a result of these differences, NASAUs
Office of Advanced Concepts and Technology expects that if the
experimental commercialization centers at Ames and JSC are
successful, this concept could be extended to other NASA centers
and could be used as models for other federally-funded
laboratories.
The cooperative agreement with the University of Texas, IC2
Institute, calls for about $400,000 funding for each of the two
centers this year, with funding rising to approximately $1 million
a year at each of the centers for 1994 and 1995. Total program
funding is $5.4 million over the 3-year life.
- end -
Source:NASA Spacelink Modem:205-895-0028 Internet:192.149.89.61
=--=--=-END-=--=--=
=--=--=START=--=--= NASA Spacelink File Name:6_8_12_2.TXT
NOTE: This file is too large {16758 bytes} for inclusion in this collection.
The first line of the file:
FACT SHEET: THE CASSINI MISSION
Source:NASA Spacelink Modem:205-895-0028 Internet:192.149.89.61
=--=--=-END-=--=--=
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