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发信人: bage (网事如疯·春心萌动), 信区: AerospaceScience
标 题: SpaceViews -- 2000 November 6(转载)
发信站: 哈工大紫丁香 (2000年12月23日12:08:31 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 2000.45
2000 November 6
http://www.spaceviews.com/2000/1106/
*** News ***
Space Station Alpha Crew Settles Into Daily Routine
The Name Game: Bill Shepherd, Tradition and the Politics of
Space Travel
NASA: No Room at the ISS Inn for Mir Cast-offs
MirCorp's Future Is Barometer For Space Business
Chance of Asteroid Impact Downgraded
Space Station Lifeboat Sails to Success in Desert Test
Asteroid Nanorover Scrapped; NASA/Japan Cooperation Still On
China Launches Navigation Satellite
Scientists Fail to Save Ultraviolet Explorer Spacecraft
Clinton Signs Bill to Fund NASA for Two Years
SpaceViews Event Horizon
Other News
*** Articles ***
What Is a Planet? Debate Forces New Definition
Editor's Note: Technical problems delayed the delivery of this issue
from Monday morning (US East Coast time) to Tuesday afternoon. We
apologize for the delay.
*** News ***
Space Station Alpha Crew Settles Into Daily Routine
By Todd Halvorson
Cape Canaveral Bureau Chief
SPACE.com
An American astronaut and two Russian cosmonauts settled in
aboard Space Station Alpha Friday, gearing up for the long haul -- and
a spartan existence -- aboard the international outpost.
A day after arriving at the infant station, the so-called
Expedition One crew was back at it again, setting up critical
computer, communications and carbon dioxide removal systems -- all key
to keeping Space Age pioneers alive in low Earth orbit.
What follows over the next four months will be workdays that
stretch up to 15 hours, six days a week. And the crew -- which
includes Bill Shepherd, Yuri Gidzenko and Sergei Krikalev --
essentially will be on call around the clock.
They'll be living in what amounts to a cluttered three-room
efficiency -- and one of the station's wings will remain off limits
until early December.
There are only two bunks for the three men, and they'll wear
earplugs at times to drown out industrial clatter created by station
equipment.
They'll have e-mail, but no Internet connection, and space-to-
ground radio or video contact with family and friends will come weekly
at best.
With no washer or dryer, they'll wear disposal clothes, and
since taking a shower in weightlessness is more of a chore than a
pleasure, they'll opt for daily sponge baths.
What's more, there's no booze aboard.
"This is not the Hilton," NASA flight director Jeff Hanley
said in perhaps the understatement of the early 21st century.
Still, the three veteran space fliers already are adjusting to
the no-frills lifestyle.
"How do you feel, guys?" a flight director at the Russian
Mission Control Center outside Moscow asked the station's inaugural
tenants as they began their first full day of work on Alpha.
"Seems like everything is fine," said Krikalev, a consummate
spaceman who already has spent almost 500 days in orbit aboard space
shuttles and Russia's Mir space station. "It feels like home by now
already."
"That's terrific," the Moscow ground controller replied.
That's not to say, however, that the trio's planned four-month
stay on the station won't be hardship duty. The crew made that quite
clear in preflight interviews.
The daily grind
Take a typical day aboard the station. And forget the
traditional wake-up music enjoyed by NASA shuttle crews.
Instead, a buzzing, alarm clock-like tone will blare out of
station speakers at 1 a.m. Eastern Standard Time (06:00 GMT) every
day, rousting Shepherd, Gidzenko and Krikalev from sleeping bags
tethered to keep them from floating about during the night.
Their Russian-made crew quarters is equipped with only two
closet-like "staterooms," so one of the station residents is staking
out some personal space elsewhere in the module -- probably in front
of one of its 13 windows.
Still unclear is exactly who is the odd man out.
The line then forms at the station's cramped bathroom at the
start of a 90-minute period set aside for breakfast and morning
hygiene -- cleaning up, brushing teeth and shaving. Some, however,
prefer to let their whiskers grow.
"We haven't had enough time to grow a beard yet," Krikalev
told flight controllers Friday. "But we'll have our chance."
Then at 2:30 a.m. EST (07:30 GMT), the crew will check e-mail,
catch up on news beamed up from home and review a "to-do list" of
chores to be completed during the day ahead.
A half-hour later, the crew will chat with ground controllers
about scheduled jobs and then work will begin in earnest each day at
3:15 a.m. EST (08:15 GMT).
All three of the station residents will squeeze two hours of
exercise in between their household tasks -- a mandatory regimen meant
to combat bone and muscle loss caused by long-term stays in
weightlessness.
It's not unusual, though, for a station crew to fall behind
the so-called "timeline."
Shepherd and company, for example, struggled to get all their
work done after their arrival at the station Thursday. Then they faced
a few more pesky problems Friday trying to get power tool battery
chargers and food warmers working properly.
"We worked really hard yesterday, and we could not keep up
with the timeline. And we're way behind today, too," Shepherd told
colleagues in NASA's Mission Control Center in Houston.
"Hooking up the food warmer was scheduled for 30 minutes, and
it took us a day and a half to finally figure out how to turn it on,"
he added. "You'll just have to be patient with us."
The food warmers -- which resemble hot plates -- are
instrumental for making the mid-day meal, which comes about 7 a.m. EST
(12:00 GMT) each day. And then it's back to the orbital salt mines
until 1:15 p.m. EST (18:15 GMT).
Another chat with ground controllers comes at that point -- to
review work completed and schedule jobs for the following day. Then
the crew has about two hours free time to clean up, eat dinner and
prepare for the next day's onslaught -- in theory, that is.
Twenty Four Seven
As a practical matter, a station crew is pretty much working
round the clock, making certain that all outpost systems are humming
along, keeping residents alive.
"We are staying basically kind of in our job site and offices
for 24 hours a day," Krikalev said before the Expedition One launch.
"So even if you sleep, you're monitoring what is going on. If
noise on the station changes -- it can be not loud, it can be not
quiet, just change a little bit -- you wake up and try to see what's
going on," he said. "You're kind of on duty all the time."
For the Alpha crew, that will mean keeping close tabs on all
critical life support systems within the 13-story station, which now
is made up of three habitable wings.
They include the station's crew module, which doubles as a
command post; a Russian space tug now serving as a warehouse; and a
U.S. docking module that ultimately will provide a pressurized
passageway to all parts of the growing station.
The interior of the 80-ton station, however, is quite cramped.
Some 6,300 kilograms (14,000 pounds) of supplies and equipment
were stowed inside the crew module and the Russian tug by four
visiting space shuttle crews. The tug is particularly cluttered up,
with stowage bags covering its floor and hanging from its walls.
Shepherd told flight controllers Friday that the advance
moving crews did an admirable job.
"There's a lot of stuff in there, but it is pretty ship shape,
" he said. "I think they made the best of a bad situation, trying to
keep it all squared away. It's about as orderly as it could be in
there."
The stowed supplies primarily are parts of the critical
computer, communications and life support systems the Expedition One
crew now is putting in place. Much of the mess, as a result, will be
cleared away within the next few weeks.
That will free up some breathing room within the station, but
the expansive American docking module is off limits until shuttle
Endeavour arrives in early December with a giant pair of power-
producing solar arrays.
The station now lacks the power needed to keep temperatures,
humidity and other conditions within the $300 million module suitable
for the crew.
Little time to play
What little spare time the crew manages to find will be spent
relaxing station-style.
Shepherd, a 51-year-old Navy captain, plans to read The Sand
Pebbles, a fictional 1962 best seller by Richard McKenna. An
accomplished garage mechanic, he also brought along an array of power
tools to play with.
"I'm planning on spending a lot of time trying to figure out
how things work (on the station), and if they are not working, I'll
take them apart and put them back together and see if I can at least
not make things worse," the veteran astronaut said prior to flight.
Gidzenko, a 38-year-old Mir veteran, brought along his musical
favorites: The Beatles, The Rolling Stones and a selection of Russian
folk songs. But the Russian Air Force colonel prefers to stay busy to
ward away the blues.
Onboard Mir, Gidzenko discovered that the holidays could be
especially difficult if he didn't keep himself occupied. And the
Expedition One crew will spend Thanksgiving, Christmas, New Years and
Valentines Day in space before a Feb. 26 return to Earth.
"Sometimes it was very difficult because all other days we had
a lot of things to do, and that's why the time flowed very quickly,"
Gidzenko told reporters recently. "When we had a little bit of spare
time, it was a time when I thought about Earth and sometimes we miss
that."
Krikalev, meanwhile, expects to take full advantage of the
view from above.
"I spent more than 15 months in space (aboard Mir), and I
didn't read much in space," the 42-year-old aerospace engineer said
prior to flight. "Every time you have a choice between just going to
look outside or reading a book, (I think) you can read back here on
the ground."
There's one other thing that will have to wait until the crew
sets foot back on terra firma: The cocktail hour.
An occasional shot of vodka or cognac is not out of the
question aboard Mir, but there's always been an unwritten rule
prohibiting liquor on American space vessels.
"We're a dry ship now," admitted Shepherd, a man who enjoys a
tall, cold beer.
"There's no authorized supply of alcohol on board," senior
NASA project manager Jim Van Laak added before planting his tongue
firmly in his cheek.
"It comes up when the handball court comes up."
The Name Game: Bill Shepherd, Tradition and
the Politics of Space Travel
By Alan Ladwig
V.P. Washington Operations
SPACE.com
Call Bill Shepherd the Alpha Male of the International Space
Station.
During his first official communiqué with Mission
Control, the tenacious Commander of the Expedition One crew extracted
a pledge out of NASA chief Daniel S. Goldin to refer to the orbiting
lab with the name "Alpha."
Whether this means that the more generic handle of the
"International Space Station" and its acronym "ISS" will be
permanently retired remains to be seen.
Naming the station has been high on Shepherd's priority list
for the past seven years. A believer in the Navy tradition to give
ships of exploration a specific name, he feels that "the people who
design and build these vessels launch them with the good feeling that
a name will bring good fortune to the crew and success to their
voyage." Prior to launch, Shepherd and crewmate Sergei Krikalev stated
they had a good feeling for the name Alpha.
Senior NASA officials have not been all that concerned about
the name-challenged laboratory. In fact, when informed of the crew's
comments on the name, Administrator Goldin stated, "It's not Shep's
place to name it." With a hint of irritation he added, "You want to
know something? Let's work on building the station. We can get
diverted with issues like that."
Shepherd's surprise request fell short of asking for a
permanent name change for the research facility. He merely asked
Goldin for "permission to take the radio call sign Alpha." Clearly
caught off guard by the request, Goldin only agreed to the request
"temporarily" until the end of Expedition One.
The use of the modifier "temporary" now has space officials
wondering what will come next. NASA spokesman Dwayne Brown said as far
as he was concerned, the lab "is still the International Space
Station." Brown "fully believes" that Shepherd's request to use Alpha
"is not unlike a call sign for a F-16 pilot." However, call signs in
the military tend to be claimed by individual pilots, not their
aircraft.
If it is decided to christen the station with a new name it is
not clear how the process would be conducted. One official admitted
that agreeing upon a name can be "a painful process." Issues of
culture, language interpretations, and acronym usage can become
complicated when dealing with 16 nations.
An inter-agency process in 1993 agreed upon five suitable
names including, Alliance, Unity, Freedom, Aurora, and Alpha. Jeff
Vincent, who at the time was the head of NASA public affairs, recalled
that a list of pros and cons were generated for each name and
presented to Administrator Goldin. From this list, the name Alpha was
selected and forwarded to the Clinton White House for approval.
The decision package eventually ended up on the desk of the
presidential policy advisor George Stephanopoulos. According to a
former staffer who was part of the White House review gauntlet,
Stephanopoulos questioned the need for a new name and wanted to know
why the former Space Station Freedom designation couldn't be applied
to the new configuration.
A second letter was sent over, this time recommending the name
Freedom. From there, however, the trail has grown cold. No one seems
to know, or is willing to tell, exactly why a decision was never made.
Lynn Cline, NASA's deputy chief for international affairs
believes that the international partners would be comfortable with the
five names that came from the 1993 initiative. Cline cautioned
however, that she had not yet had an opportunity to address the issue
with her counterparts in other countries.
Another unknown variable involves the Russians. They were not
yet official ISS partners when the five names were recommended. Yuri
Semenov, the head of the aerospace company Energia and a person of
influence in the Russian space program, disapproves of Alpha. To him,
Alpha implies "the first," which he believes is a slight to the 15-
year-old Mir space station. Semenov would rather see the station named
Beta or the clearly dead-on-arrival suggestion of Mir 2.
With assembly of the orbiting outpost seemingly now on track,
space managers are hoping to bring stability to operational procedures
by referring design and process changes to a Management Control Board.
With representatives from the partner nations, at least one NASA
public affairs official felt this group could entertain station name-
change requests.
Jason had the Argo. Columbus had the Nina, Pinta, and Santa
Maria. Cousteau had the Calypso. And now, Bill Shepherd has his Alpha.
As Dan Goldin indicated, now Shep can "sleep well at night and not
have any concerns."
NASA: No Room at the ISS Inn for Mir Cast-offs
By Andrew Bridges
Pasadena Bureau Chief
SPACE.com
As a trio of pioneer astronauts takes up residence at the
International Space Station (ISS) this month, the first thing they
might want to do is flick on the "No Vacancy" sign.
For the station, an eight-year, $60 billion, 16-nation effort,
won't be hosting paying guests anytime soon -- at least not as far as
NASA is concerned.
"While we're building the ISS, this is not the time to do
something like that. In the early part of the program there is lot of
work to be done and equipment to be installed. It's not a pleasure
cruise," said Brian Welch, a NASA spokesman.
At least one paying tourist may visit space next year all the
same, but aboard a different ship. American businessman Dennis Tito is
scheduled to make a $20 million trip to the Russian's Mir this winter,
thanks to MirCorp, the company seeking to lease the space station for
commercial and tourist use
However, the Russians -- short the $200 million it would take
to maintain the teenaged Mir through 2001 - may well scuttle that plan
by crashing the orbital outpost to Earth.
That would leave Tito, MirCorp and the winner of the upcoming
reality-based television program Destination: Mir without a
destination.
However, should Mir fall, the Russians may allow tourists to
fly to the cooperatively built and owned Enterprise module on the ISS,
a joint project of SPACEHAB and RKK Energia, Russia's largest
aerospace firm. Enterprise is tentatively scheduled to be launched in
2003.
But such a venture would first have to be cleared with all the
international partners involved in the station. A task far more
complicated than smaller commercial deals, like say, sewing a beer
company-emblazoned patch on a Canadian astronaut's uniform.
"If a proposal was going to affect life aboard the station
and... day-to-day operations and the environment -- which something
like [tourists] would do -- all partners would have a say in that,"
Welch said.
However, NASA will not even consider such a proposal while the
ISS is under construction, a task that will take at least until 2006
to complete.
"It's not what anyone would be able to consider lodging. It's
got a real industrial feel, out there on the frontier," Welch said.
"We wouldn't rule out entertaining notions like that in the future,
but right now we're not interested."
MirCorp's Future Is Barometer For Space Business
By Mary Motta
Senior Business Correspondent
SPACE.com
The recent news about MirCorp's financial woes is a sign that
Wall Street does not consider zero-gravity space ventures a zero-sum
game, industry experts say.
"The problem with new space ventures is that they have at
least two hurdles to jump," said Ray Williamson, a research professor
at the Space Policy Institute. "Where do you get capital and how do
you convince investors that a space venture is a viable business
economically, or that it will be in the future?"
The Russian government, which owns Mir, stopped financially
supporting the station last year but has leased commercial rights to
Amsterdam-based MirCorp.
MirCorp has been scrambling to raise money to save the station
to make money from commercial ventures on the aging space lab.
Executives of the company, which has spent more than $40 million this
year to keep Mir alive, said the battle is not over.
"The victory of MirCorp is far from dead," said company
spokesman Jeffery Lenorovitz.
He said that one of MirCorp's major investors, Chirinjeev
Kathuria, spent time last week in New York feeling out the market for
the company's initial public offering.
"I have been talking to investment banks and lawyers and
everyone is interested," said Kathuria. "Both the IPO and the plan to
bring a strategic partner in are both on track."
Kathuria said that both he and telecommunications entrepreneur
Walt Anderson have decided to invest another $12 million into the
project. "We will announce it in the next three to four weeks," he
said.
Despite Kathuria's optimism, some experts still believe that
coming up with the kind of money that Mir needs won't be an easy task.
"The market for investment in projects involving long
durations in space is just not there yet," said Frank DiBello,
managing director at space venture-capital firm SpaceVest.
The station, first launched in 1986, needs to be kicked up
into a higher orbit as a result of drag from the thinner upper
atmosphere -- an expensive project to undertake.
Late last week, Russia earmarked funds for two supply rockets
to Mir, but left the fate of the nearly 15-year-old outpost undecided,
Russian officials said.
The remote-controlled Progress ships will carry fuel to Mir,
which could be used to boost the massive station into a higher orbit
and extend its life, or to lower it into the atmosphere for a
destructive controlled reentry into the Pacific Ocean.
The Cabinet allocated $27 million to pay for the two cargo
ships, but put off a decision about Mir's fate until February, Deputy
Prime Minister Ilya Klebanov said.
Lenorovitz said MirCorp Chief Executive Jeffery Manber is in
Russia meeting with officials to explain its financial plans to keep
Mir in orbit.
MirCorp's Manber, who wrote a letter to Russian President
Vladimir Putin stating Mir's case, may have his work cut out for him.
In the letter, published in the Russian newspaper Kommensant,
Manber appealed to the Russian leader's sense of national pride,
warning that Russia's participation in the International Space Station
(ISS) would not guarantee that the struggling nation's scientific and
economic interests would be protected.
Manber hoped MirCorp and Putin would "jointly find the way to
keep the Mir space station in orbit," reminding the president that
earlier this year the he had stated his firm intentions to save the
almost 15-year-old outpost.
However communications between the company and Russian space
officials has been static at best since the venture was first hatched
earlier this year and the letter was coolly received by the Russian
Space Agency, Rosaviakosmos.
Reports of the space outpost's future have been upbeat on this
side of the Atlantic, with MirCorp spokesmen exuding confidence that
Mir's business plan will remain viable.
"We are a real company and we have real revenue," Lenorovitz
said.
Other reports, however, have indicated a darker outlook for
the station. This cacophony of voices has ranged from NASA sources to
Russian officials pointing to February as the likely window for Mir's
fiery return to Earth.
Russian Deputy Prime Minister Ilya Klebanov said this month
that members of the government had recommended that the station be
left to forces of gravity.
Russian Aviation and Space Agency spokesman Sergey Gorbunov
last week went as far as to deny that investment tycoon Dennis Tito,
who reportedly paid about $20 million to be the first space tourist,
has trained for the trip to Mir at Russia's Star City.
"There were no official documentation substantiating his
training," he said.
MirCorp's Lenorovitz shot back after hearing Gorbunov's claim.
"We've got pictures!" he told SPACE.com. "We had 40-some
journalists who attended the press conference in Space City announcing
Tito's training."
One industry insider said that this breakdown in communication
is common when it comes to doing business with the Russians.
"Fyodor Tyutchev, a 19th-century philosopher said it best,"
the industry official said. "Russia cannot be understood with the
mind, it can only be believed in."
In fact, a survey this year by Boston-based Marttila
Communications Group found that 69 percent of Russians polled think
the West wants their economy to collapse. Eighty-seven percent believe
the United States is taking advantage of Russia's current weakness to
expand its global influence. Only 13 percent regarded the U.S. as a
friend or ally; 28 percent described it as an enemy.
Despite the swirl of bad news for the beleaguered space
station, MirCorp officials argue that it is worth saving because blue-
chip advertisers can be lured into the final frontier.
Within the past couple of years, the station has scored a few
notable deals. Pepsi-Cola shelled out $1.5 million for the honor of
having cosmonauts open a can of Pepsi in space before an international
TV audience.
And Pizza Hut slapped its logo on the side of a rocket bound
for Mir to the tune of $1.2 million.
"When you are at the cutting-edge of things, it's not an ideal
world," Lenorovitz said. "MirCorp has drawn a line in the sand and
said 'this is how things were done before, and this is the way they
are going to be done from now on.' "
Chance of Asteroid Impact Downgraded
By Jeff Foust
Special to SPACE.com
Just a day after astronomers warned that a near-Earth asteroid
had a small chance of colliding with the Earth in 2030, new data
released Saturday ruled out an impact but raised the possibility that
the body could pose a threat to the Earth in the future.
The new data came in the form of "pre-discovery" observations
made in May of this year by the Catalina Sky Survey in Arizona, four
months before University of Hawaii astronomers discovered asteroid
2000 SG344. The observations were reanalyzed on Friday after the
International Astronomical Union (IAU) announced that the asteroid had
a 1-in-500 chance of colliding with the Earth in September 2030.
Those observations allowed astronomers to refine the
asteroid's orbit and more accurately determine its position in the
future. The new orbit shows that the asteroid will pass no closer to
the Earth than 4.3 million kilometers (2.7 million miles), or 11 times
the distance of the Moon, in 2030, thus eliminating any possibility of
an impact.
The new observations do not shed any light on the nature of
the asteroid, however. Based on its brightness astronomers estimate it
is 30 to 70 meters (100 to 230 feet) in diameter. However, its unusual
orbit leads astronomers to speculate that it could be the spent upper
stage of a rocket booster dating back to the Apollo era.
While 2000 SG344 poses no risk to the Earth in 2030,
astronomers have not ruled out the possibility that is could collide
with the Earth later in the 21st Century. "While the new orbital
calculations have ruled out the 2030 event, they have also increased
the likelihood of encounters in years after 2030." Don Yeomans,
manager of NASA's Near-Earth Object office at JPL, said in a statement
Saturday. "For example, for the date September 16, 2071, current
computations indicate roughly a 1-in-1000 chance of an Earth impact."
Friday's announcement of the possible impact of 2000 SG344
based on limited data - and the rapid retraction of that threat - may
generate controversy among astronomers still smarting from the 1997
XF11 asteroid scandal of 1998. In March 1998 astronomers said that
asteroid had a small chance of colliding with the Earth in 2028.
Additional data released a day later eliminated the threat. That
episode led the creation of new guidelines by the IAU for reporting
impact threats that were followed for 2000 SG344.
Space Station Lifeboat Sails to Success in Desert Test
By Andrew Bridges
Pasadena Bureau Chief
SPACE.com
NASA successfully tested the latest prototype of an emergency
rescue boat for the International Space Station on Thursday, just
hours after the orbiting outpost received its first tenants.
For now, the X-38 prototype was dropped not from the space
station Alpha, but from under the right wing of a B-52 aircraft,
making a nine-minute cruise to a safe landing in California's Mojave
Desert.
"The landing was beautiful. It was perfect," said Leslie
Williams, a spokeswoman at NASA's Dryden Flight Research Center in
Edwards, California.
The free flight was the first for the latest incarnation of
the X-38 Vehicle 131-R, an 80-percent scale version of the actual crew
return vehicle (CRV) that NASA hopes one day will serve to ferry as
many as seven astronauts to Earth in the event of an emergency aboard
the space station. For now, astronauts must rely on a Russian Soyuz
module to beat a hasty retreat.
The B-52 dropped the X-38 prototype at 12:20 p.m. Eastern
Standard Time (17:20 UT) from an altitude of 11,000 meters3 (6,500
feet). The lifting body, based on a design borrowed from a 1970s U.S.
Air Force research project, made an unexpected 360-degree roll after
it was jettisoned.
About thirty seconds into the flight, the uncrewed prototype's
24-meter (80-foot) drogue parachute snapped open, leaving the CRV to
slowly rotate, counterclockwise, as it recovered from the roll and
fell toward the desert floor.
Less than a minute later, the drogue dropped off as the
world's largest successfully flown parafoil unfurled. The 675-square-
meter (7,500-square-foot) parafoil jerked the CRV at first, and then
allowed it to settle down for the remainder of its trip to Earth.
However, the parafoil -- one and a half times larger than the wingspan
of a Boeing 747 jet -- deployed while the CRV was in a nose-up
attitude, a glitch that fortunately caused no damage.
By 12:29 p.m. EST (17:29 UT), the CRV skidded to a halt,
leaving a short furrow in the reddish desert soil just 0.8 kilometers
(one half mile) from its original target. The craft landed at a slight
angle, as it had pointed leftward as much as 30 degrees during its
final seconds of flight, a NASA commentator said. Touchdown speed was
less than 64 kilometers per hour (40 mph).
"Today our design faced a test. Most systems worked well, some
didn't," said John Muratore, the X-38 program manager, in a statement.
"We're going to take the results of this test, improve the design, and
we will be back to test it again."
The purpose of the flight was to evaluate the CRV's final
aerodynamic configuration for actual production models. The flight
also used for the first time European Space Agency-contributed
parafoil guidance software.
Unlike previous flights, the majority of this drop test --
including the landing -- was autonomous.
NASA will continue to test the prototype this year and into
next. In August 2002, the agency hopes to release an uncrewed X-38
from the space shuttle to fly back to Earth and land.
Asteroid Nanorover Scrapped; NASA/Japan Cooperation Still On
By Andrew Bridges
Pasadena Bureau Chief
and Leonard David
Senior Space Writer
SPACE.com
NASA has canceled work on the MUSES CN nanorover, a tiny
wheeled robot that a Japanese spacecraft was to have dropped off to
roam across an asteroid in 2005.
The miniature rover would have been launched in 2002 as part
of Japan's MUSES C mission to return samples to Earth from the
asteroid 1998 SF 36. A NASA official said Friday that a formal letter
informing the Japanese of the decision to scrap the rover is en route.
Two issues lay at the root of the problem, Jay Bergstralh,
NASA's acting director of solar system exploration, told SPACE.com.
"Money and mass, both growing and no real end in sight," he said.
The 2.5-pound (1.1-kilogram) NASA rover, which was slated to
embark on a one-month tour of the asteroid, would have been by far the
smallest wheeled robot ever dispatched to explore another world. It
would have been equipped with visible-light and infrared cameras.
"It's a little hard for me to disentangle what all happened,"
Bergstralh said of the decision to halt work.
The estimated $180 million mission originally was to visit the
asteroid (10302) 1989 ML, also known as Nereus. However, problems with
the Japanese M-5 rocket -- which failed in a February attempt to hoist
that nation's Astro E X-ray observatory into orbit and was to launch
the MUSES C spacecraft -- forced a launch delay to late 2002.
Subsequently, the Japanese moved to select a new target for
its spacecraft to visit. The mission still aims to return samples of
the asteroid to Earth for study by 2007.
Furthermore, the rover saw its estimated cost balloon from $21
million to nearly three times that amount in recent years.
NASA said it will hold discussions with Japan's Institute of
Space and Astronautical Science (ISAS) on how else it might contribute
to the mission, formally known as the Mu Space Engineering Spacecraft
C.
"We still intend to cooperate with the Japanese on the MUSES C
mission," Bergstralh said. U.S. co-investigators are on some of the
spacecraft's instruments, he said, and ISAS, one of Japan's space
agencies, has asked NASA for tracking and communications support for
the asteroid mission.
Presumably, work on the nanorover might have some future
application for Mars exploration, Bergstralh said. The tiny rover was
always considered a technology-development program. "It was not
primarily driven by science," he said, adding that NASA will continue
working on the nanorover's development.
The tiny rover would have for the most part rolled around the
asteroid with the help of its four wheels.
However, later in the mission, engineers envisioned the rover
attempting several scissors-kick moves that would allow it to jump
about in a gravity environment perhaps one-one hundred-thousandth that
of Earth.
Louis Friedman, executive director of The Planetary Society, a
Pasadena, California space exploration advocacy group, blasted the
decision to can the rover.
"It's a terrible disappointment. It's a loss for science, a
loss for technology and a big loss for international cooperation,"
Friedman said.
Friedman added it seemed that NASA was returning to the era of
launching a single, large mission once a decade from the heady days
promised by NASA Administrator Daniel Goldin, who foresaw launching
swarms of spacecraft -- built better and more quickly and cheaply than
ever before -- every year.
"It's like watching a movie in reverse," Friedman said, as
canceled NASA missions, including the nanorover, the 2001 Mars lander
and -- in all likelihood, a Pluto flyby -- pile up.
China Launches Navigation Satellite
By the Associated Press
for SPACE.com
China put a navigation satellite into orbit Tuesday, the first
link in a domestically engineered system designed to lessen the
country's dependence on foreign technology.
The Long March 3-A rocket blasted off from southwestern
China's Xichang launching center a few minutes after midnight and
successfully placed the Beidou navigation satellite into orbit, the
government's Xinhua News Agency reported.
The satellite is the first in a series for the system that
will provide all-weather, round-the-clock navigation information for
highways, railways and shipping, Xinhua said.
The satellite was developed by China's Research Institute of
Space Technology, Xinhua said. It did not say how many other
satellites China intends to launch for the system and when the network
will be operational.
Xinhua applauded the scientific prowess that went into the
satellite and noted the successful rocket launching was China's 21st
in a row without a mishap since 1996.
Satellite systems allow for more accurate tracking of
everything from cargo ships to missiles. The world's most accurate
satellite tracking network, the Global Positioning System, was built
by the United States and is maintained by the Department of Defense
for both commercial and military uses.
As it tries to build up its economy and military, China has
been leery of becoming too dependent on foreign technology. A five-
year plan for economic development, approved by the ruling Communist
Party three weeks ago, calls for boosting the country's high-tech
sector.
By the plan's end in 2005, Chinese technology should reach the
level attained by developed countries in the mid-1990s, and China
should create some leading-edge technologies, the party's People's
Daily newspaper reported Tuesday.
Xinhua reported that the military's politically influential
general in charge of weapons development, Cao Gangchuan, observed the
satellite launching in Xichang.
Scientists Fail to Save Ultraviolet Explorer Spacecraft
By Leonard David
Senior Space Writer
SPACE.com
So long...it's been good to know you. Scientists petitioning
NASA and the U.S. Congress have failed to save the Extreme Ultraviolet
Explorer (EUVE).
The astronomical observatory -- designed to be space-shuttle
serviceable and retrievable -- is headed for doom. It will plunge to
Earth between late 2001 or early-to-mid 2002.
"Unfortunately we were unable to mobilize sufficient support
to obtain Congressional help," said Roger Malina, EUVE director, at
the University of California, Berkeley. "As a result, EUVE will
shortly terminate operations," he said in a "Dear EUVE colleagues"
letter distributed Thursday.
Healthy but terminated
The astronomical eye-in-the sky spacecraft continues to
operate flawlessly. The EUVE has produced a steady stream of data
since its launch in July 1992. But a steady-stream of money, about a
$1 million per year, could not be found to keep spacecraft operations
going.
Malina pointed out that the EUVE detected an enormous flare
earlier this week. The source was among the brightest EUVE had ever
detected.
"It will be decades before astronomers have access to the
extreme-ultraviolet band. The unobservable ultraviolet will soon be
unobservable again!" Malina said.
Extreme ultraviolet is a form of light that falls between X-
rays and ultraviolet radiation. Material heated to 200,000 degrees
Fahrenheit (111,093 degrees Celsius) emits extreme ultraviolet
radiation. This type of radiation cannot be detected by the human eye.
Senior review panel
NASA is expected to announce the demise of EUVE shortly.
"The fact of the matter is that EUVE operated for eight years.
That is more than twice its planned lifetime," said Dolores Beasley, a
NASA spokeswoman.
"The decision to end the mission was based on findings from a
senior scientific review panel. EUVE did indeed open a new window on
the universe by letting us observe extreme-ultraviolet light. But yes,
the decision has been made," Beasley told SPACE.com.
Funding to close out the project runs through December,
Beasley said. A NASA statement regarding the reentry of EUVE is
forthcoming, she said.
Clinton Signs Bill to Fund NASA for Two Years
By Craig Linder
Special to SPACE.com
President Clinton signed into law a bill funding NASA for the
coming two years lasts week, but he expressed concern about some of
the act's provisions.
The National Aeronautics and Space Administration
Authorization Act of 2000 permits the space agency to spend $14.2
billion in 2001 and $14.6 billion in 2002, but places a cap on further
American spending on the International Space Station (ISS).
"This bill falls short of enabling NASA to conduct the most
balanced, efficient and effective space program," Clinton said.
The NASA authorization bill -- the first in several years --
caps the agency's space station spending at $25 billion on building
the ISS and $17.7 billion on space shuttle missions necessary to haul
supplies and materials to the orbiting construction zone.
President Clinton said that the cap "limits NASA's flexibility
to pursue a promising commercial habitation module for the
International Space Station."
A NASA spokeswoman declined to elaborate on Clinton's
statement, saying, that it "speaks for itself."
White House spokesman Jason Schecter said that Clinton also
objects to one provision in the law that requires NASA to notify
Congress within 90 days of a decision to replace any Russian elements
of the ISS program. The president also objects to a second that would
require the space agency to certify before Congress before reaching
any agreement with China on spacecraft, launches or scientific
information.
Also included in NASA's funding is $221 million for the Triana
project, a controversial effort to launch a satellite into outer space
that would provide constantly updated images of the sunlit side of
Earth to the Internet.
The Triana project was first proposed by Vice President Al
Gore in 1998 and swiftly attacked by Republicans in Congress as a
waste of taxpayer funds. A March report National Research Council
said, however, that the program had scientific merit.
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.
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
November 14 Ariane 5 launch of the PAS-1R communications satellite
from Kourou, French Guiana at 8:07 pm EST (0107 UT
November 15)
http://www.coola.com/cgi-bin/addinfo.cgi?pid=10003&rid=972904568&type=D
November 16 Soyuz launch of a Progress cargo spacecraft for the
International Space Station from Baikonur, Kazakhstan
http://www.coola.com/cgi-bin/addinfo.cgi?pid=10003&rid=972904632&type=D
November 18 Delta 2 launch of the Earth Observing 1 and SAC-C
science satellites from Vandenberg Air Force Base,
California at 1:27 pm EST (1827 UT).
http://www.coola.com/cgi-bin/addinfo.cgi?pid=10003&rid=973486398&type=D
Other News
Distant Planet Search Fails: An effort to search for planets in a
distant globular cluster has come up empty, a result which may
actually bolster theories of planet formation. Astronomers took more
than 1,300 images of the cluster 47 Tucanae, 1,300 light-years from
the Earth, over an eight-day period in an effort to look for dimming
of any of the cluster's 35,000 stars that would be caused by a planet
passing in front of it. However, the Hubble Space Telescope images
showed no such dimming, indicating a dearth of planets in the cluster.
The result is not necessarily surprising, since the globular cluster
is made of older stars that likely lack the heavy elements needed for
planet formation.
Globalstar Woes, Iridium Hope: Globalstar, the satellite phone
company, may be on the same road to bankruptcy that Iridium traveled,
analysts warned this week. The concerns came after reports that
Loral, which owns 38 percent of Globalstar, will not invest any more
money into the company. The company reported that, through the first
nine months of the year, it has lost $652 million on revenues of just
$2.5 million, and that the company has only 21,300 subscribers, far
short of the 5000,000-1.3 million needed for the company to break
even. The company, which tapped a $250 million line of credit earlier
this year, does still have $286 million in cash, enough to last
through May of next year... Meanwhile, a new suitor has appeared for
Iridium that may keep the bankrupt company's constellation of
satellites in operation. Iridium Satellite LLC has proposed to
purchase Iridium's assets for $25 million, a small fraction of their
original cost. Motorola, the company that currently operates the
satellites, has endorsed the bid and had offered a $30 million loan to
continue operating the satellites until control is handed over to
Boeing, who would operate the satellites for Iridium Satellite LLC. A
November 8 court hearing is planned to review the bid.
Lunar Fraud Conviction: A man who tried to pass off terrestrial rocks
as lunar samples pled guilty last week to six counts of mail and wire
fraud. Richard Keith Mountain admitted in a federal court in Arizona
that he tried to see ordinary rocks as lunar samples from the Apollo
11 mission. Mountain now faces up to five years in prison and a $250,
000 fine; sentencing is planned for next January.
Laser Rocket Record: A laser-propelled spacecraft set a new altitude
record for such a vehicle during a test flight at White Sands, New
Mexico, last month. A 10-kilowatt laser propelled a 51-gram (1.8-oz.)
"lightcraft" to an altitude of 71 meters (233 feet), higher than any
previous laser-powered vehicle, during an October 2 test. The
groundbased laser strikes a reflector on the base of the lightcraft
that is coated with material that ablates and propels the vehicle
upward. Leik Myrabo, inventor of the lightcraft and CEO of Lightcraft
Technologies, told SPACE.com he has big plans for the vehicle. "Every
time we go out we're going to try and double the altitude," he said.
"We need six more doublings to get to the edge of space."
*** Articles ***
What Is a Planet? Debate Forces New Definition
By Robert Roy Britt
Senior Science Writer
SPACE.com
Traditional views of what makes a celestial body a planet, in
place for centuries and defined almost entirely by the nine with which
we're most familiar, have become thoroughly antiquated in five short
years as a host of new objects have been discovered.
And so the word "planet" will be redefined by the world
organization authorized to do so, SPACE.com has learned. The change
could come as early as mid November.
In fact, the International Astronomical Union (IAU), charged
with classifying heavenly objects, has never had a definition on
record for planets. Never needed one. Everyone instinctively knew what
a planet was.
But starting in 1995, discoveries of huge planets around other
stars, plus new objects that are neither planet nor star, have forced
the IAU to draw some distinctions. The movement gained momentum in
recent weeks with the announcement of free-floating objects in space
that look like planets.
Exoplanets and brown dwarfs
Since the first planet was discovered orbiting another star in
1995, more than 50 extrasolar planets, or exoplanets, have been found.
These planets are nothing like what we're used to. They are huge --
often many times the mass of Jupiter -- and some are altogether more
like another class of object, the brown dwarf.
Suspected since 1963 and confirmed to exist in 1995, brown
dwarfs are failed stars. Though huge, they never grew massive enough
to initiate the thermonuclear fusion that drives a real star. Yet most
brown dwarfs are enormous compared to the planets in our solar system.
They can be up to 75 times as massive as Jupiter.
"While a planet emits no visible light, a brown dwarf emits
just enough to be detected. Yet some appear very planet-like. They can
have a diameter closer to Jupiter's and, frequently, orbit a star just
as a planet would."
Adding to this confusion are the objects that freely drift
though space. A batch of 18, revealed in October, have been called
planets. But this designation is totally counter to the notion that a
planet is something that orbits a star.
Though the free-floaters might be brown dwarfs, they have the
light signatures of planets, and they are just five to 15 times as
massive as Jupiter, a size range typically thought to be planetary.
"We are beginning to see this whole series of objects that we
were not able to detect before, and it's completely changing our ideas
of planetary formation and the mass of the objects we find," said
Morris Aizenman, a senior science associate in the Mathematical and
Physical Science Directorate of the National Science Foundation.
Aizenman and others say planetary and stellar sciences are
undergoing a revolution. The definition of a planet, meanwhile, is
crumbling under the weight of discovery.
Problems big and small
At the other end of the size spectrum, tiny Pluto should never
have been called a planet in the first place, most mainstream
scientists agree.
Pluto is less than half the size of any other planet, and its
orbit is at a distinct angle from the plane in which the other planets
travel around the Sun. Most significant, Pluto roams so far beyond the
orbit of Neptune that researchers say it is part of the Kuiper Belt, a
region of distant, frozen rocks only confirmed to exist in 1992.
"If we'd known about the Kuiper Belt when Pluto was discovered
[in 1930], it would have been a giant Kuiper Belt Object," said
Michael A'Hearn, a University of Maryland astronomer and past
president of the IAU's Planetary Systems Sciences division.
In early 1999, the IAU wrangled over giving Pluto dual status
-- both as a planet and as a Trans-Neptunian Object, reflecting its
distant location. The plan was dropped after a public outcry led to
hundreds of e-mails to the IAU.
Collectively, the smaller bodies in the solar system,
including comets and asteroids, have come to be called minor planets
(a term that is also being debated). A'Hearn said the all the
definitions are fluid for good reason: Scientists are still figuring
out what the objects are.
Even in our own backyard. A'Hearn and others say it's
reasonably likely that another object as big or larger than Pluto will
be found orbiting the Sun even farther out. What happens then?
"Start the fight over again," A'Hearn said.
Textbook definition? Good luck
Finding a textbook definition for the word "planet" is tricky.
Amazingly, many science and astronomy books -- just like the IAU --
don't define the word. You won't find a basic definition in the New
York Public Library's Science Desk Reference, for example. And in the
1999 edition of Universe, a comprehensive tome used widely in college
courses, "planet" is not even an entry in the 21-page glossary.
How could this be?
Just five years ago, before any brown dwarfs or exoplanets had
been confirmed, there was a wide gap between the largest planet we
knew of - Jupiter -- and the smallest known stars, which were 75 times
the mass of Jupiter.
"That made things nice and simple. Textbook simple," said the
Carnegie Institution's Alan Boss, who heads the 13-member IAU group
that's trying to define "planet." "You could say, 'This is a star, and
this is a planet.'"
So simple we didn't need a textbook definition.
"Now, we realize things are not so clear," Boss said in an
interview. With the recent discovery of free-floating planet-like
objects, a months-old definition hammered out by the IAU group after
much debate is already outdated, he added.
"We're kind of starting all over again," Boss said. A draft
recommendation might be ready for review in two weeks, he added. But
first, there are some thorny issues to sort out.
Three areas of difference
The gray areas between planets and brown dwarfs boil down to
three things: their genesis, their orbit and their size.
If there were a textbook definition of planet, it would likely
describe an object that forms out of the swirling disk of gas and dust
left after the formation of a star. This is how our nine planets
formed. Jill Tarter, director of the SETI Institute, favors this
definition for a planet.
But Tarter, who coined the term "brown dwarf" back in 1975
when the objects were only theoretical, explains that you can't always
tell how an object formed. So she would also include the requirement
that the object orbits a star.
While this seems like an instinctive definition for a planet,
it doesn't account for the recently discovered planet-like objects
roaming freely in space. (Perhaps the ancients saw this coming: The
Greek root of the word "planet" means "to wander.")
To further complicate matters, brown dwarfs can meet the above
two "planet" requirements. They frequently are found orbiting a star
in what scientists call a binary arrangement, implying that they
formed out of the original disk of gas and dust.
Much of the current debate, therefore, centers on size.
And when a brown dwarf is about 13 times the mass of Jupiter,
it generates enough pressure to force the burning of deuterium, a
hydrogen-like element. Planets cannot burn deuterium.
"Most people, but not all, would make the dividing line at
whether or not deuterium burns," said A'Hearn, the University of
Maryland astronomer.
This still leaves areas of confusion, allowing the possibility
of some brown dwarfs that are less massive than other objects that
would be classified as planets.
At least a star is a star -- Right?
Brown dwarfs are the ill-defined middle ground between planets
and stars. A star is a star because it shines on its own, generating
light through thermonuclear reactions in which hydrogen is converted
to helium. Brown dwarfs, though they can burn deuterium in another
type of reaction called "core fusion," fall short of full-blown
stellar thermonuclear fusion.
But brown dwarfs can, like stars, be born out of an otherwise
unorganized cloud of gas and dust, when gravity forces a direct
collapse of the cloud.
And even stars cross the blurry lines of definition.
"The fact is that stars form in disks as inevitably as
planets," explained astronomer Gibor Basri of the University of
California, Berkeley. This happens in binary-star systems, where one
star forms first and the other is created from the leftovers.
One shot at a definition for planets
Basri, who has written about brown dwarfs for Scientific
American, just this week completed the draft of a paper titled "What
is a Planet?". He shared the draft with SPACE.com.
In the paper, Basri discussed the two possible ways that free-
floating planets, among the most vexing objects, might have formed.
"One is that they formed in planetary systems around
stars...and were subsequently ejected from the system," Basri wrote.
"The other possibility is that these objects formed in isolation, or
at least were not originally bound to a star."
Either way, Basri suggested that existing terms and
definitions are no longer sufficient. Some new terms and definitions
are needed to cut through the scientific and cultural roadblocks that
prevent clear and accurate distinctions between planets and other
objects.
"A planet is a spherical object never capable of core fusion,
which is formed in orbit around an object in which core fusion occurs
at some time."
Or, if that's too much of a mouthful, Basri has a shorter
version:
"A planet is a spherical non-fusor born in orbit around a
fusor."
Gone, it seems, are the days when our idea of a planet was so
simple it didn't even need a definition.
========
This has been the November 6, 2000, issue of SpaceViews.
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