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发信人: bage (网事如疯·春心萌动), 信区: AerospaceScience
标 题: SpaceViews -- 2000 October 23(转载)
发信站: 哈工大紫丁香 (2000年12月23日12:08:37 星期六), 转信
【 以下文字转载自 bage 的信箱 】
【 原文由 hitsma@0451.com 所发表 】
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S P A C E V I E W S
Issue 2000.43
2000 October 23
http://www.spaceviews.com/2000/1023/
*** News ***
Shuttle Wraps Up Station Work, Waits to Return Home
Even If MirCorp Finds Funds, Will It Be Too Late?
Russian Soyuz Rocket Lifts Progress Toward Mir
ILS Proton Sends GE Satellite Into Orbit
Sea Launch Scores Another Success With Record-Breaking
Satellite
Air Force Atlas Sends New Military Communications Satellite
Into Orbit
"Titanic" Discovery: Earth-Like Weather and Methane Rain
11 Billion-Year-Old Gamma Burst Discovered in Space
SpaceViews Event Horizon
Other News
*** Articles ***
Is a Vacation in Space Far-Out Fantasy, Or Close to Reality?
*** News ***
Shuttle Wraps Up Station Work, Waits to Return Home
[Ed. Note: this article is a compilation of articles filed by
SPACE.com Cape Canaveral Bureau Chief Todd Halvorson over the last
week.]
The crew of the space shuttle Discovery completed work that
prepared the International Space Station for both its first long-term
crew and future assembly missions last week.
While the STS-92 astronauts encountered few problems during
their time on the station, the crew is now dealing with a problem
beyond their control: high winds in Florida that have already delayed
their landing one day and may force them to land in California for the
first time in more than four years.
Adding a docking port
In a job deemed crucial to a carefully choreographed station
construction plan, Japanese astronaut Koichi Wakata plucked a 2-ton
docking port from shuttle Discovery's cargo bay Monday and then deftly
eased it by a fragile station solar array just inches away.
The second of four planned spacewalks for Discovery's mission
kicked off about 10:15 a.m. Eastern Daylight Time (1415 UT) Monday as
the shuttle was flying some 384 kilometers (240 miles) above Earth.
Spacewalkers Jeff Wisoff and Michael Lopez-Alegria made their
way up to the work site to help Wakata guide and mount the docking
port to its intended berthing spot on the so-called "Unity" module,
one of three pressurized wings that now make up the station.
During the seven-hour, seven-minute spacewalk, the duo also
routed power cables between the port and the $300 million Unity
module, bringing the new addition to life electrically.
The installation job cleared the way for launch of NASA's next
outpost construction crew aboard shuttle Endeavour, a flight now
scheduled for November 30.
The new docking port also will provide a parking place for
shuttle Atlantis on a mission now scheduled for launch in mid January.
The cargo for that flight - a U.S. lab that will serve as the
scientific heart of the station - is to be attached to the port where
Discovery is now docked.
Wiring work
Working side-by-side three stories above shuttle Discovery,
astronauts Leroy Chiao and Bill McArthur bolted bulky transformers in
place on a station truss Tuesday as the towering outpost loomed above
them.
Shaped like a giant cube, the $273 million truss will serve as
a temporary mounting platform for a pair of power-producing solar
arrays to be launched aboard shuttle Endeavour on November 30.
The spacewalking work carried out by McArthur and Chiao
largely was aimed at prepping for the arrival of the huge solar
panels, which will have a wingspan of 73 meters (240 feet) once
unfurled in orbit.
The boxy power converters they installed will route
electricity to the station from the arrays. Like large transformers on
Earth, the converters will reduce and regulate the amount of voltage
being fed into the outpost.
Other mop-up work included stowing a toolbox outside the
station and removing a keel pin that had been used to hold the new
truss in the shuttle's cargo bay during Discovery's launch last week.
McArthur and Chiao repositioned the pin up inside the truss to make
way for the soon-to-be-delivered solar arrays.
Testing jetpacks
Shuttle Discovery's astronauts stole a chapter out of a Buck
Rogers book Wednesday, test-flying jet backpacks that one day might
save construction workers cast adrift from the International Space
Station.
Floating high above their mothership, astronauts Jeff Wisoff
and Michael Lopez-Alegria zoomed down to the edge of the bay,
mimicking the type of flight spacewalkers would face if they
accidentally tumbled off into the deadly vacuum of space.
Wisoff made the first test run, starting out at a point 15
meters (50 feet) above Discovery's payload bay. Anchored to the end of
the shuttle's lengthy robot arm, Lopez-Alegria remained nearby,
playing out Wisoff's standard safety tethers like fishing line.
Following a highly choreographed test regime, Wisoff first
flew around a small imaginary box to see how well the 38.5-kilogram
(85-pound) jetpacks steered.
Pulsing the jetpack's tiny jet thrusters, Wisoff then flew
slowly and deliberately toward his target -- a TV camera mounted in
the rear of the shuttle's cargo bay.
A second rescue drill -- one aimed at seeing whether an
unconscious astronaut could be hauled back to the shuttle for medical
attention -- was called off due to a lack of time. More critical mop-
up work with a newly installed station truss took longer than
expected.
That work involved removing a grapple fixture that enabled
Japanese astronaut Koichi Wakata to latch onto the truss with the
shuttle's robot arm and put it in place on one of three permanent
wings that now make up the 80-ton station.
Wrapping up station work
After completing the spacewalks, the crew turned their
attention to the interior of the station, ultimately pronouncing the
outpost in shipshape for the early November arrival of its first full-
time tenants.
STS-92 commander Brian Duffy and crew spent the day testing
the station's new dome-shaped gyroscopes, which are designed to reduce
the amount of fuel needed to keep the outpost properly positioned in
orbit. Four of the devices are housed within a 9-ton truss mounted
atop the station by the Discovery crew last week.
The astronauts also finished up some interior wiring work,
took air samples and hauled laptop computers, hard drives, tools and
spare electrical equipment into the growing complex from crew-cabin
storage lockers aboard Discovery.
"This is a beautiful place," shuttle skipper Brian Duffy said
as his crew mates scurried about the 13-story station, stowing
supplies and conducting systems tests in advance of the planned
October 31 launch of the so-called Expedition One crew.
"They're just putting the finishing touches on so that when
the Expedition One crew arrives, everything will be perfect for them,"
Duffy said. "I think they're really going to be happy to get here."
Undock and wait
With rookie pilot Pam Melroy at the controls, Discovery inched
away from the 13-story station at 11:08 a.m. Eastern Daylight Time
(1508 UT) Friday as the two craft soared above the Amazon River Basin
near Brasilia, the capitol of Brazil.
Discovery's high-flying departure came after a morning-long
scramble to finish up work inside the station and then close hatches
between the shuttle and the outpost.
A messy shuttle toilet repair job -- coupled with station
systems tests that took longer than expected -- conspired to put the
crew behind schedule Thursday.
Consequently, the wrap-up work within the outpost was put off
until Friday, delaying the crew's departure by about 90 minutes.
"I think we can declare victory," NASA flight director Chuck
Shaw said.
Astronauts planned to return to Earth with a Sunday afternoon
landing at the Kennedy Space Center. However, high winds in Florida
conspired to scrub the two landing opporunities available then.
Strict NASA flight rules call for a daytime landing attempt to
be called off if runway crosswinds top 15 knots, and peak gusts at the
concrete strip were well above the safety threshold.
"It was actually an easy call," NASA flight commentator Kyle
Herring said. "The winds stayed out-of-limits almost all day."
Look for NASA to try to bring Discovery and its crew home for
a 2:51 p.m. Eastern Daylight Time (1851 UT) landing here at the
shuttle's Florida homeport.
The agency also will have a second KSC landing opportunity at
4:28 p.m. EDT (2028 UT), but gusty winds are expected to be a problem
in central Florida once again.
Landing support teams, as a result, will be on hand Monday at
Edwards Air Force Base, which is located about 136 kilometers (85
miles) north of Los Angeles.
Discovery and its crew will have three opportunities to land
at the Mojave Desert military base. The first will come at 4:22 p.m.
EDT (2022 UT). The others will be at 5:58 p.m. EDT (2158 UT) and 7:34
p.m. EDT (2334 UT), respectively.
Forecasters expect a chance of rain at Edwards Monday but
conditions there are expected to improve during the course of the
week.
A landing at Edwards would be the first since shuttle Atlantis
touched down there in March 1996 to complete a mission to Russia's Mir
space station.
NASA prefers to land shuttles at KSC because it costs about $1
million and takes about a week to ferry an orbiter from California
back to Florida atop a modified 747 jumbo jet.
A California landing also would delay preparations for
Discovery's next flight -- a mid-February station construction and
outpost crew rotation mission.
Even If MirCorp Finds Funds, Will It Be Too Late?
By Yuri Karash
Contributing Moscow Correspondent
SPACE.com
Key players in the Russian Aviation and Space Agency
(Rosaviacosmos) met Thursday to discuss the future of Mir, but failed
to dispel the deepening questions surrounding the ailing space
station's future.
"No decision was made at this meeting regarding Mir's fate,"
Sergey Gorbunov, Rosaviacosmos spokesman, told SPACE.com in an
exclusive interview. "The attendees just discussed different variants
of what to do with Mir in the future."
Needless to say, the specter of the 15-year-old space
station's decaying orbit hung heavy over the heads of the designers
and officials at the meeting, including Yuri Semenov, president and
general designer of RKK Energia, which owns the complex, and Yuri
Koptev, general director of Rosaviacosmos.
While a recently launched Progress cargo vehicle is on course
to boost the station to a higher orbit that will remain viable through
February, the fate of Mir beyond that point remains unclear.
"The idea of the station's deorbiting was dominating the
meeting," said Gorbunov. "Everybody understood that there was no other
choice for Mir but to be deorbited. This understanding was, however,
just a recognition of the fact that there will be no money to keep Mir
in orbit and it should not be considered as a formal decision."
That said, the officials considered another option. Continued
operation of the space outpost -- which Dutch company MirCorp had
planned to lease through 2001 and beyond for commercial and tourist
purposes -- remained on the table, although Gorbunov was not
optimistic about the possibility.
"MirCorp is currently begging Energia on its knees not to
deorbit the station," he told SPACE.com. "They are promising to find
money in three weeks, but it will be too late anyway. Spaceships
cannot be manufactured in a couple of days."
Russian Soyuz Rocket Lifts Progress Toward Mir
By Jim Banke
Senior Producer,Cape Canaveral Bureau
and Yuri Karash
Moscow Contributing Correspondent
SPACE.com
What may turn out to be the final mission to carry supplies to
the aging Russian space station Mir successfully lifted off from the
Baikonur Cosmodrome in Kazakhstan early Monday evening, according to
program officials in Moscow.
The Soyuz rocket lifted off at 5:27 p.m. Eastern Daylight Time
(2127 UT) and at the top was a pilotless Progress vehicle, which
safely separated from the booster's second stage about nine minutes
after launch.
Loaded with 2,318 kilograms (5,109 pounds) of fuel and 532
kilograms (1,172 pounds) of equipment -- which includes such things as
food, clothes, office supplies, videotape and personal items --
intended for a future space station crew, the Progress is now on a
four-day chase to rendezvous and dock with Mir.
Normally it takes about two days for Progress to reach Mir,
but Russian flight controllers altered their plans at the last minute
-- delaying the launch 24 hours -- and instead found a way for the
spacecraft to make the trip in four days by using less fuel.
The Progress docked with the orbiting outpost at approximately
6:50 p.m. EDT Friday (2250 UT).
The extra fuel, officials say, will be used to help raise the
altitude of Mir's orbit and prolong the life of a station that has
been in space for nearly 15 years.
That's good news for MirCorp, a Holland-based firm that has
the exclusive rights to lease Mir for commercial purposes.
The company, which recently announced its intention to sell
stock, has plans to launch U.S. businessman Dennis Tito as a "Citizen
Explorer" in 2001 and the winner of an NBC series from "Survivor"
producer Mark Burnett called "Destination Mir" in 2002.
However, the Russian Space Agency and other government
aerospace enterprises are under pressure to safely bring Mir out of
orbit to crash into the ocean so that scarce money and supplies can be
devoted to meeting Russia's commitment to the International Space
Station.
If the decision to dump Mir is executed, at least one more
Progress-type vehicle would be launched to bring fuel to the station
to power a controlled dive into Earth's atmosphere.
ILS Proton Sends GE Satellite Into Orbit
By Jim Banke
Senior Producer, Cape Canaveral Bureau
SPACE.com
Another communications satellite is safely in orbit today
following launch Saturday night of a Proton rocket from the Baikonur
Cosmodrome in Kazakhstan.
Known as GE-6, the GE American Communications satellite will
provide direct broadcast television programming, as well as a host of
other typical communication services, to users in North and Central
America.
The Lockheed Martin-built spacecraft was launched into space
at 6 p.m. Eastern Daylight Time (2200 UT) using a four-stage Russian
Proton rocket marketed by International Launch Services (ILS).
Following a normal flight plan for the Proton, it took more
than six hours before the satellite arrived in its proper orbit and
was separated from the rocket, ending the launch phase of the mission.
This was the fifth ILS Proton launched this year and the 18th
overall in the history of ILS, the joint venture between Lockheed
Martin in the United States and Khrunichev and RSC Energia in Russia.
Still ahead for ILS before the end of the year: a Proton
launch carrying a Sirius radio satellite.
The next launch from planet Earth is scheduled for early this
coming Saturday morning from South America when an Ariane 4 rocket is
to loft into orbit an European communications satellite.
Sea Launch Scores Another Success With Record-Breaking Satellite
By Jim Banke
Senior Producer, Cape Canaveral Bureau
SPACE.com
The world's heaviest commercial communications satellite was
launched into orbit from the Pacific Ocean early Saturday in a bid to
offer mobile telephone service to more than 1.8 billion people.
But you'll have to live in a region encompassing parts of
Asia, Africa or Europe to enjoy the services of the 5,108-kilogram
(11,260-pound) Thuraya-1 spacecraft that was built by Boeing Satellite
Systems for the United Arab Emirates-based Thuraya Satellite
Telecommunications Company.
"We will be offering the service in almost 100 countries,"
said Thuraya chairman Muhammad Hassan Omran.
Similar in concept to the plans of U.S.-based companies such
as Globalstar and the now-defunct Iridium, Thuraya wants to offer cell
phone service that uses both standard ground systems and a satellite
to relay voice and data transmissions.
Thuraya's hand-held units also boast the capability to receive
Global Positioning System navigation information, telling the user
almost precisely where they are on the planet.
To get the hand-held units small enough so customers more
handily accept them, the orbital satellite had to be extremely
powerful -- and consequently very heavy, said George Torres, a
spokesman for Boeing Satellite Systems.
"The complexity is on board the satellite," Torres said.
Formerly Hughes Space and Communications, the new Boeing unit
began operating this month after government regulators approved
Boeing's acquisition of the Hughes property -- a milestone Saturday's
launch has helped the Boeing team celebrate.
"It was just last week we had our big Day One celebration when
we became Boeing," Torres said. "It's fitting that we start this phase
with Boeing because this is the largest, heaviest commercial
communications satellite ever produced."
Boeing's contract to build two satellites for Thuraya as well
as the associated ground stations and provide more than 70,000
handsets is worth more than $1 billion, Torres said.
Thuraya-1 was carried into orbit by a Zenit-3SL rocket
launched from the Odyssey Launch Platform in the Pacific Ocean by Sea
Launch, the joint venture of companies representing the United States,
Ukraine, Russia and Norway.
Liftoff came at 1:52 a.m. Eastern Daylight Time (0552 UT) and
the satellite separated from the top of the Zenit about two hours
later.
"That is a major milestone in the mission," said Sea Launch
mission commentator Steve Rondinaro. "Thuraya-1 is on its own now."
The good news conclusion to the shot now gives Sea Launch an
80 percent success rate over five launches. The third mission --
launched this March -- failed because of a computer program fault that
was fixed and proven on the fourth mission launched in July.
"Sea Launch has a great future," said company president Wil
Trafton. "We're very pleased to be where we are. We're going to be
around for a long time."
Giving support to Trafton's comments, Thuraya's chairman
announced at the post-launch celebration that Thuraya-2 will be
launched on Sea Launch when the satellite, which was built as a ground
spare, is needed.
In the meantime, the next Sea Launch is expected early next
year, Rondinaro said.
Air Force Atlas Sends New Military Communications Satellite Into Orbit
By Jim Banke
Senior Producer, Cape Canaveral Bureau
SPACE.com
A brilliant prime time night launch witnessed by thousands of
people along Florida's Space Coast ended successfully Thursday when a
military communications satellite was thrown into orbit over Earth.
The $200 million Defense Systems Communications Satellite
(DSCS) took its ride atop an Air Force Atlas 2A rocket, launched from
complex 36 at Cape Canaveral Air Force Station.
Liftoff came at 8:40 p.m. Eastern Daylight Time (0040 Friday
UT) and the mission concluded when the Lockheed Martin-built
spacecraft separated from the Lockheed Martin-built rocket some 26
minutes later, injecting the satellite into a near perfect orbit over
the equator.
"That's pinpoint placement," said launch commentator Don
Spencer. "As usual, (the rocket) performed its job and put the
spacecraft right where we want it to go."
Thursday's space shot marked the 53rd success in a row for the
Atlas rocket -- a good news streak that has stretched some seven years
-- but the launch team had to work hard to see their booster off.
A variety of technical troubles at the launch pad, last-minute
concerns about the weather, a problem with a range station in the
Indian Ocean and a barge in the offshore launch danger zone all
contributed to delaying the liftoff almost one hour past the
originally targeted 7:36 p.m. EDT (2336 UT) launch time.
The DSCS satellite launched Thursday joins 11 others already
in orbit as the Air Force works to build a total constellation of 14
spacecraft to serve military communication requirements.
Complementing the capabilities of the Pentagon's super-
powerful Milstar communications satellites, these third-generation
DSCS satellites allow soldiers in the field to keep in touch with
commanders on the other side of the planet by sending and receiving
voice and data transmissions.
A key feature of the DSCS satellites is that they provide
uninterrupted service, even if an enemy attempts to jam the signal by
setting off nuclear explosions.
The Department of Defense began this satellite program in
1966, launching 26 birds in the first phase of the project and 16
second generation spacecraft starting in 1971.
"Titanic" Discovery: Earth-Like Weather and Methane Rain
By Robert Roy Britt
Senior Science Writer
SPACE.com
In one of the most distant weather reports ever received,
clouds and even rain showers seem to have been spotted on Titan,
Saturn's largest moon. Along with vast seas and modest mountains, a
picture is emerging of a place more like Earth than anywhere else in
the solar system.
Scientists have already labeled Titan a hot spot in the search
for extraterrestrial life, and the new work adds to that enthusiasm.
Titan is a cold, dark, smog-shrouded world larger than the
planet Mercury and nearly half as big as Earth. Known for decades as
the only moon in the solar system with an atmosphere, Titan has many
of the raw materials for life, including nitrogen, carbon and water.
But at 1.4 billion kilometers (886 million miles) away from
the Sun, most if not all of Titan's water is locked in ice. So the
distant moon's rain is of a different sort, thought to be methane --
the primary component of the common heating fuel, natural gas. Methane
is also an important raw material for other organic compounds.
In a new study, researchers looked at non-visible light
emitted by Titan, spotting small clouds that developed and disappeared
daily, most likely after causing a methane rain shower.
The results of the study, which confirm earlier suspicions
about Earth-like weather on Titan, appear in the October 20 issue of
the journal Science.
"Titan is a planet-sized laboratory hosting perhaps the kinds
of organic chemical reactions that preceded and initiated life on
Earth 4 billion years ago," said Jonathan Lunine, a professor at the
Lunar and Planetary Laboratory who was not involved in the study. "To
see methane in action as a cloud-forming and rain-forming condensate
lends further credence to the view that Titan is a very attractive
astrobiology target."
The driving force
On Earth, weather is largely driven by heat from the Sun,
which creates temperature differences that move large masses of wind
and foster huge oceanic currents. But Titan receives about 100 times
less solar energy; temperatures hover around -178 degrees Celsius (-
288 degrees Fahrenheit).
So a different force is thought to drive weather on Titan,
weather that is mild by terrestrial standards.
"We propose latent heat [released when a gas condenses] plays
a large role in driving Titanian weather," said Caitlin Griffith, lead
researcher. "These bizarre conditions conspire to bring about strange
clouds. On Titan, clouds are rare, usually covering less than 1
percent of the globe, compared to the Earth's 50-percent coverage."
Titan's gravity is only about one-seventh that of Earth. The
intense chill, however, means a low-energy atmosphere that hangs
around, instead of escaping this relatively weak force of gravity. So
Titan's atmosphere is denser than Earth's and extends much higher into
the sky.
Titan's clouds hover about 25 kilometers (15 miles) up, said
Griffith, a researcher at Northern Arizona University in Flagstaff.
Earth's clouds, by contrast, range from the ground to occasionally as
high as 17-18 kilometers (11 miles) in the middle of the worst
thunderstorms and hurricanes.
While weather is relatively docile on Titan, and rainfall is
probably sparse, it may come down in buckets now and then.
"Most rivers on Titan may run dry, but river valleys may
nevertheless be abundant and deep," writes the Lunar and Planetary
Laboratory's Ralph Lorenz in an analysis of the study.
Search for life
Increasingly, Titan is being seen as a good place to look for
extraterrestrial life. Like Jupiter's moon Europa, Titan is expected
to be hiding liquid water in its belly, says Lorenz, who models
geophysical processes on Titan's surface but did not work on
Griffith's study.
Lorenz said Titan's surface is too cold for liquid water, the
requirement for life as we know it. But deep beneath the surface, it
may be warm enough to melt the ice.
And already, researchers have evidence of simple organic
molecules -- similar to gasoline -- on the smoggy moon. These
molecules are very far from life, but are a first step, says Lorenz.
"The one thing Titan does have on its side is all these
organics, which Europa doesn't have," Lorenz told SPACE.com. "That
gives it better stuff to work with to create life -- a more 'hearty'
primordial soup, if you like."
Let's go see
There is no evidence that either Titan or Europa do harbor
life, and scientists agree that we won't know until more research is
done, most likely with a spacecraft to perform direct measurements.
Answers may come as soon as 2004. The Cassini spacecraft, en route to
study Saturn, its rings and moons, is scheduled to drop the Huygens
probe into Titan's atmosphere.
The probe will take readings in the atmosphere during a 2.5-
hour descent. On the surface, it is expected to survive and collect
data for at least three minutes, and perhaps longer.
But a recently discovered hardware problem aboard Cassini may
leave it unable to receive much of the science data the probe will
collect. The European Space Agency hopes to have a plan in place to
deal with the glitch by next summer.
Meanwhile, firm proof that clouds exist on Titan may depend on
the Huygens probe. One researcher who studies Titan and is familiar
with Griffith's study isn't entirely convinced of the findings.
"I don't think we can say for sure one way or the other at
this point" whether the clouds exist, said Athena Coustenis of the
Paris-Meudon Observatory. Coustenis said the results need to be
confirmed by other researchers.
11 Billion-Year-Old Gamma Burst Discovered in Space
By Jeff Foust
Special to SPACE.com
A gamma-ray burst detected earlier this year is the most
distant burst ever detected and may prove to be a valuable barometer
researchers can use to explore the conditions of the early universe,
astronomers announced Wednesday.
An international team of astronomers, discussing their work at
a gamma-ray burst conference in Rome, Italy has traced the origin of
GRB 000131 to an unseen galaxy 11 billion light-years away, implying
that the burst took place when the universe was only a couple billion
years old. (1 light-year is the distance light travels in one year --
about 6 trillion miles, or 9.7 trillion kilometers.)
The burst was detected on January 31 by the gamma-ray
detectors of the Interplanetary Network, a trio of spacecraft --
Ulysses, NEAR, and Wind -- in various regions of the solar system. The
detections by the three spacecraft allowed astronomers to triangulate
the coordinates of the burst and train other telescopes on that
position to study the aftermath of the event.
At first GRB 000131 did not seem particularly different from
other gamma-ray bursts, which are detected by spacecraft at the rate
of about once a week.
"The flash of high-energy gamma radiation appeared at first to
be relatively normal," explained Kevin Hurley, the University of
California Berkeley physicist who operates the Interplanetary Network.
"It was neither very faint, which might indicate that it had traveled
a long way from its source, nor very bright, which would hint at a
somewhat closer origin."
The burst's unusual nature was determined only in the
following days, when European astronomers, using telescopes at the
European Southern Observatory (ESO) in Chile, studied the fading
optical counterpart, or afterglow, to the GRB. Images of the afterglow
showed it was much redder than those of other bursts, implying that
the light was redshifted and thus emanated from billions of light-
years away.
An accurate determination of the GRB's distance came from a
spectrum of the burst taken on February 8. By that time the afterglow
had faded considerably, down to magnitude 25.3, requiring a three-hour
exposure with one of the four 8-meter (315-inch) telescopes of the
Very Large Telescope (VLT) at ESO. In that spectrum astronomers
identified a characteristic set of features known as the "Lyman-alpha
forest", created when clouds of hydrogen gas absorb ultraviolet light.
Astronomers found the Lyman-alpha forest not at ultraviolet
wavelengths, but at much longer visible-light wavelengths, indicating
that the light had been redshifted by a factor of 4.5.
This redshift corresponds to a distance of about 11 billion
light-years, making GRB 000131 the most distant burst observed,
beating out the previous record-holder by more than 2 billion light-
years.
Because the burst is so distant, it took place in the early
history of the universe -- no more than approximately 2 billion years
after the Big Bang -- and thus gives astronomers another way to
understand what the early universe was like.
"What is important is that we have a technique to sample the
deep universe in a manner not believed possible a few years ago," said
Holger Pedersen, an astronomer with Copenhagen University in Denmark.
"Finding the most remote gamma-ray bursts should be a good way to
trace the early phase of galaxy formation."
What the burst doesn't solve, though, is the mystery behind
GRBs themselves. Some astronomers believe that such bursts are
generated by hypernovae -- explosions of massive, short-lived stars
that are a thousand times more powerful than a typical supernova. The
difficulty in studying such bursts, particularly distant ones like GRB
000131, mean that the mechanisms behind a GRB are still poorly
understood.
New spacecraft and telescopes may provide astronomers with the
resources to better understand GRBs, however. NASA's High Energy
Transient Explorer 2 (HETE 2) spacecraft, launched earlier this month,
will soon alert astronomers to GRBs within 10 to 20 seconds of their
detection, allowing telescopes such as the VLT to observe the optical
afterglow when it is far brighter. "If observations can start within,
say, five minutes, optical light may then be many thousand times
brighter than we saw it in GRB 000131, allowing for much more detailed
observations," said Pedersen.
Such techniques may also aid astronomers in discovering even
more distant bursts. "The observation of this burst can be viewed as
another rung in the distance ladder," said Hurley. "Everything about
gamma-ray bursts has proven to be a complete surprise to us, and this
observation is a good example. Our data may indicate that we can
indeed see much farther still."
SpaceViews Event Horizon
Note: You can now add these events to your Palm handheld by clicking
on, or copying and pasting into a Web browswer, the URL below each
event. Visit Coola's Web site at http://www.coola.com/ for more
information about this free service.
October 23-27 32nd Annual American Astronomical Society Division for
Planetary Sciences Meeting, Pasadena, California
http://www.coola.com/cgi-bin/addinfo.cgi?pid=10003&rid=968079363&type=D
October 28 Ariane 4 launch of the Europe*Star FM1 communications
satellite, from Kourou, French Guiana at 1:59 am EDT
(0559 UT)
http://www.coola.com/cgi-bin/addinfo.cgi?pid=10003&rid=972300485&type=D
October 31 Soyuz launch of a Soyuz spacecraft carrying the
Expedition One crew to the International Space
Station, from Baikonur Kazakhstan at 2:52 am EST
(0752 UT)
http://www.coola.com/cgi-bin/addinfo.cgi?pid=10003&rid=972300557&type=D
November 7-9 Canadian Aeronautics and Space Institute's 11th
Conference on Astronautics, Ottawa, Ontario
http://www.coola.com/cgi-bin/addinfo.cgi?pid=10003&rid=972300639&type=D
November 9 Delta 2 launch a GPS navigation satellite, from Cape
Canaveral, Florida at 12:18 pm EST (1718 UT)
http://www.coola.com/cgi-bin/addinfo.cgi?pid=10003&rid=972300703&type=D
Other News
Congress Passes NASA Spending Bills: Congress passed a budget bill
last week that appropriates $14.285 billion for the space agency in
fiscal year 2001, $250 million more than requested by NASA and $633
million more than NASA's 2000 budget. The bill fully funds several
key projects, including programs like the Space Launch Initiative and
"Living with a Star" solar studies effort that had faced cuts earlier
in the budget process. "This measure provides an excellent budget for
NASA," administrator Dan Goldin said Friday. "Our supporters in the
Congress faced considerable difficulties in reaching this outcome, and
we should all be very grateful for their championing of the Nation's
civil space and aeronautics program." Earlier in the week the
Congress also passed an authorization bill for NASA for 2001 and 2002,
the first such legislation Congress has passed for the agency in
years. That bill authorizes the $14.2 billion for 2001 as well as
$14.6 billion for 2002. Congress will still have to appropriate the
2002 funds next year.
Huge Star Similar to Sun: In a discovery expected to upset
conventional thinking about stellar physics, researchers have found
plasma-trapping magnetic fields at work on a star 30 times bigger than
our Sun. The finding implies that processes once thought to exist only
on Sun-like stars may be common throughout the universe. Data from
the Chandra X-Ray Observatory show that the star Zeta Orionis, a giant
O-type star, has more X-ray plasma than expected from current models
for such stars, implying that the star may have magnetic loops like
our own far-smaller Sun that can achieve the plasma densities inferred
from the Chandra data. "It really turns upside down what we've been
thinking about these hot O-stars, because we thought that these
massive stars did not have that sort of magnetic activity," said
Andrea Dupree, an astrophysicist at the Smithsonian Astrophysical
Observatory not involved with the work.
New Gemini Images: In a demonstration of its potential resolving
power, infrared images released Monday by the new 8.1-meter (319-inch)
telescope of Hawaii's Gemini Observatory gave astronomers the most
detailed look yet at the exotic nature of our galaxy's center. Those
images have helped astronomers better understand one unusual object
located just a few light-years from the galactic core. IRS8, an object
that appeared as little more than a smudge in previous images of the
region, is revealed in the Gemini images to be star plowing into a
cloud of gas and dust. "Never before have we seen such a large area of
the galactic center this clearly," says Francois Rigaut, the Gemini
Observatory astronomer who led the project, the first scientific use
of the new telescope. By releasing the images, observatory officials
also hope to impress astronomers with the quality of data possible
with the new telescope. "This is the first scientific data to be
released to the astronomical community by the Gemini Observatory,"
said observatory director Matt Mountain, "and to be able to release
such a spectacular image and data set shows the tremendous potential
of these telescopes."
*** Articles ***
Is a Vacation in Space Far-Out Fantasy, Or Close to Reality?
By Leonard David
Senior Space Writer
SPACE.com
You can't buckle up just yet. But the day of space passenger
flight is approaching faster than most people think.
Talk about "playspace".
Space tourists will become vagabond's of the vacuum. Free-
floating travelers are likely to enjoy a range of microgravity sports
and acrobatics, even taking a zero-G dip in a giant bubble of water.
In years to come, science fiction-themed hotels, spas, retreats and
conference centers will populate low Earth orbit.
The sphere of tourist travel will eventually spread outward,
with moon flights available for those craving a true getaway.
Mars also will beckon the experienced space vacationer.
As civilization settles in on Mars, families and friends will
welcome visitors from Earth. Fun times can be had by all thanks to
hiking and rock climbing in Valles Marineris. Visitors can have that
special Kodak moment with Olympus Mons, the huge volcano on Mars. They
can even hunt for fossils, or how about a little sand car racing
across Martian dunes?
Such speculation is not far out fantasy, reports a study group
of the International Space University (ISU). Over 40 young
professionals from 21 nations took part in the study: "Space Tourism
-- from Dream to Reality".
The study was done as part of ISU's summer session, recently
completed at the Universidad T閏nica Federico Santa Mar韆 in
Valparasio, Chile.
Deep space...deep pockets
Although space tourism is sure to be coming to a launch pad
near you, there's myriad technical, medical, legal and particularly
financial issues yet to be wrestled with.
"To me, it doesn't seem a stretch of the imagination to think
that we're going to get there. Market studies, how many will travel
and at what cost -- everything I see and read about space tourism says
this has to be a go," said ISU President, Karl Doetsch.
What's still missing, Doetsch told SPACE.com, is the plunking
down of major cash to create and take advantage of a blossoming space
tourism industry. But given the investment capacity of the private
sector, the magnitude of monies needed is no longer laughable, he
said.
To what extent should governments help foster public space
transit?
"They haven't yet come to grips with the question of how much
they should stimulate something that, ultimately, will be a truly
commercial venture," Doetsch said.
Doetsch believes setting up a booming space tourism business
will take some 10 to 15 years. "It's probably going to require on the
order of $10 billion to $15 billion to really move into what I call
space tourism on a large scale," he said.
"It's possible that there will be a million passengers going
into space, say before 50 years pass," Doetsch said.
The big holdup, Doetsch added, is who has deep enough pockets
filled with cash and the long-term will to make space tourism a
profitable enterprise. He agreed that, even in space, you can hear
company stockholders scream.
Fall in to the gap
For space tourism, there is no free ride.
The ISU study group flagged the gap between the current cost
of launches and the cost needed to make space tourism a self-
sustaining market. If space tourism is to be, that gap must be closed,
the report stated.
It continued, "Today's launch technology is inefficient and
complex to operate, and thus very expensive. The current commercial
market for launchers is too small to promote the development of new
technology."
Governments and space agencies, the report noted, should
invest in the research and development of reusable, safe and low-cost
launch vehicles. Private investors will also play a key role in making
space tourism a robust industry.
Other key findings of the ISU study:
* Space tourism activities will have to deal with a complex
legal framework. No specific international space law has yet been
defined for space tourism. The International Space Station will serve
as a first testing ground for laws that could later be adapted for the
space-tourism market.
* The next step in the evolutionary process of the space
tourism industry will be suborbital flights. High-altitude balloon
flights carrying passengers could help generate public interest in
suborbital and orbital jaunts.
* Space Motion Sickness (SMS) -- an illness that hits many
space travelers today -- is a concern for orbital flight passengers.
SMS drugs are key to ensuring customer satisfaction.
* Space tourism can provide the necessary launch volume to
achieve cheap access to space. Governments should help finance the
development of new launch vehicles and create a good legal framework
for the industry.
Something in the air
Angie Bukley, an airborne laser expert for The Aerospace
Corporation at Kirtland Air Force Base in New Mexico, co-chaired the
ISU study.
In its infancy, commercial aviation was only for the most
wealthy. Now, almost anyone can afford to travel by air. It's not that
big a stretch to believe that the same will be true for commercial
space transportation," Bukley said.
"Once we make the technological leap to truly affordable
access to space," she added, "then it's only a matter of time before
routine space flights are possible. At first, only the very wealthy
and healthy will be able to go. Then, as the industry evolves and
matures, it will be affordable by the general public."
There's something in the air about space tourism, said Wendell
Mendell, a space scientist at the NASA Johnson Space Center in
Houston, Texas. He co-chaired, along with Bukley, the ISU report.
"I think there will be some kind of paradigm-changing event
that will occur within the decade, and probably within the next five
years," Mendell said.
The commercialization of Mir to permit well-heeled day-
trippers is a step in that direction. Perhaps the Chinese offering
suborbital passenger flights could be another step, he said.
"I think you'll start to see things happening here and there.
When that occurs, then the world will change. My nose in the air tells
me that by 2005, I'll know whether any of these things are real within
my lifetime or not," Mendell said.
"It will be awhile before there's anything like a mass exodus.
But it will be a start."
========
This has been the October 23, 2000, issue of SpaceViews.
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