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发信人: bage (网事如疯·春心萌动), 信区: AerospaceScience
标 题: SpaceViews -- 2000 July 3(转载)
发信站: 哈工大紫丁香 (2000年12月23日17:49:38 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 2000.28
2000 July 10
http://www.spaceviews.com/2000/0710/
*** News ***
Service Module Ready for Launch
Zvezda Launch a Key Milestone for Space Station
Deep Space One Restarts Ion Engine
China Planning October Launch of Shenzhou 2
NASA Denies Computer Attack Endangered Shuttle Mission
NEAR Shoemaker Edges Closer to Eros
Laser and Microwave Sails Move Closer to Reality
Cluster Space Science Mission Moves Closer to Launch
British Rocket Takes a Step Towards the X Prize
SpaceViews Event Horizon
Other News
*** Letters ***
Galileo and Space Tourism
Note: SpaceViews editor Jeff Foust will be talking about his book,
"The Astronomer's Computer Companion," Monday night, July 10, at 8 pm
at the Book Revue bookstore, 313 New York Avenue, Huntington, New
York. Come by to meet the author and learn more computers and
astronomy!
*** News ***
Service Module Ready for Launch
The long-delayed Zvezda service module for the International
Space Station is ready for launch next week despite a minor problem
with the latest Proton launch, NASA and Russian officials said Friday.
The service module is scheduled for launch on a Proton rocket
Wednesday, July 12 at 12:56 am EDT (0456 UT) from Baikonur,
Kazakhstan. The module, mated to the booster, was rolled out to the
launch pad Saturday morning.
The launch remains on schedule despite a minor problem
reported with the last Proton launch, which placed a Russian military
communications satellite into orbit July 5. During that flight
technicians reported lower than normal pressure in the second stage
engines near the end of their scheduled burn.
At a Friday press conference, Sergei Shayevich of Khrunichev,
the Russian company that makes the Proton, said the problem with the
second-stage engines was unprecedented but minor, calling reports of
the problem in the Russian press "overdramatized". Having completed a
full investigation, he said there shouldn't be any problem for the
upcoming Zvezda launch.
Shayevich also noted that the preceding two Proton launches
that took place a week apart at the end of June were "very
successful", with no problems with their second-stage engines.
However, those two launches used older versions of the engines, while
the July 5 launch used an upgraded version of the engine that will
also be used for the Zvezda launch.
NASA officials said late Friday they plan to meet with their
Russian counterparts on Monday to make sure the issue with Proton's
engines has been fully investigated and that it poses no risk to
Wednesday's launch.
Engine problem aside, there appear to be no obstacles to
Wednesday's launch of Zvezda, after more than two years of delays.
"We're extremely delighted to be on the eve of the launch of the
service module," said Michael Baker of NASA's Moscow office.
Originally planned for launch in the spring of 1998, the
launch of Zvezda was pushed back to the end of 1999 by ongoing
assembly delays, blamed on both technical and financial problems.
While the module was ready for launch by late December, the failure of
two Proton launches in July and October of last year pushed back the
launch while the Proton's problems were investigated and corrected and
the booster completed several successful launches.
On July 25, Zvezda will rendezvous and dock with the two
existing ISS modules, Zarya and Unity. An automated docking system,
similar to the one used to dock Progress cargo spacecraft to the
Russian space station Mir, will allow Zvezda to dock with Zarya. The
two-week gap will allow ground controllers time to check out the
module's systems, Russian officials said Friday.
Zvezda is one of the critical components for the early
assembly stages of ISS. The module provides living quarters and life
support equipment for the station, additional electrical power, and
propulsion systems to maintain the station's orbit. Without the module
the station can only be occupied while docked to the shuttle.
The launch of Zvezda and the continued assembly of ISS will
not have any affect on continued operation of Russia's existing space
station, Mir. Valery Ryumin of Energia, the company that built Zvezda
and also operates Mir, said the company plans to operate Mir at least
through February of next year, the 15th anniversary of the launch of
Mir's core module.
Mir could stay in orbit much longer despite progress on ISS,
Ryumin said. "While we have investors, Mir will fly."
Zvezda Launch a Key Milestone for Space Station
This week's launch of the long-awaited Zvezda service module
is a key milestone for the International Space Station, as the module
enables both the habitability and continued assembly of the orbiting
facility.
Zvezda, Russian for "star", is scheduled for launch on Tuesday
at 12:56 am EDT (0456 UT). A Russian Proton rocket will carry the 19,
100-kg (42,000-lb.), 13-meter (43-foot) module into low-Earth orbit
from Baikonur, Kazakhstan.
Zvezda will fly free for its first two weeks in orbit, as
controllers check out the modules systems and as the module maneuvers
for its rendezvous with the two existing ISS modules in orbit, Zarya
and Unity. Docking of Zvezda with Zarya is scheduled for 9:10 pm EDT
July 25 (0110 UT July 26), as the Kurs automated docking system on
Zarya controls the docking with Zvezda, which will serve as the
passive "target" during the docking.
Should the automated docking system fail, Russia would launch
two cosmonauts to the station on a Soyuz about 15 days later. This
"Expedition Zero" crew -- so named because the first long-term crew
for the station is called Expedition One -- would dock with Zvezda and
assemble a backup teleoperated rendezvous control system, or TORU,
that they would use to dock the modules. The crew would return to
Earth shortly after the modules were docked.
Once Zvezda is docked with the rest of the station, it will
assume much of the control of the station, taking over attitude
control and reboost of the station. Computers on Zvezda will also
handle guidance and navigation of the station until computers on
Destiny, the American laboratory module, can take over next year.
Perhaps more importantly, Zvezda includes the life support
systems and living quarters to enable the station to be occupied. The
module's interior, similar in layout to the core module of Mir,
includes sleeping quarters, toilet and hygiene facilities, and a
kitchen and dining area, all enough to support a three-person crew.
The first long-term crew that will live and work in Zvezda and
the other ISS modules is scheduled for launch on a Soyuz in late
October. The Expedition One crew of William Shepherd, Yuri Gidzenko,
and Sergei Krikalev will dock with the station two days after launch
and remain there until February of next year, when the Expedition Two
crew of Yuri Usachev, James Voss, and Susan Helms -- who visited ISS
on the STS-101 shuttle mission in May -- arrive on the STS-102 shuttle
mission.
Launch of Zvezda will also release a logjam of assembly
flights to the station. In early September shuttle mission STS-106
will arrive at ISS and outfit Zvezda. A month later STS-92 will
install a truss structure that will serve as the early framework for
what will eventually become a large array of solar panels.
About a month after the Expedition One crew arrives, shuttle
mission STS-97 will install a Photovoltaic Module on the truss
structure with the first set of solar panels. That will be followed
in early 2001 with the launch of the Destiny lab module on mission
STS-98.
As the station grows, new modules will take over roles that
will initially be handled by Zvezda. However, the module will remain
the heart of the Russian portion of the station: The module includes
two docking ports for future Russian modules to attach to the station,
in addition to the docking port to be used by Soyuz and unmanned
Progress cargo spacecraft.
Deep Space One Restarts Ion Engine
NASA's Deep Space One (DS1) experimental spacecraft restarted
its ion engine late last month after seven months of dormancy, the
latest sign that engineers have overcome problems with a star tracker
that threatened the mission.
The recovery of DS1, called one of the greatest rescues in the
history of robotic space exploration by the project's leader, opens
the door for an extended mission that would include a comet flyby next
September.
DS1's problems began last November, when its star tracker, an
instrument that monitors a set of reference stars to determine the
spacecraft's orientation, failed after a series of intermittent
problems. Without the data from the star tracker, DS1 entered a safe
mode that halted normal operations.
For the last several months project engineers worked on a
software fix that would turn the spacecraft's scientific camera into a
star tracker. The new software was uploaded to the spacecraft and
tested successfully in mid-June.
To compensate for the differences between the original star
tracker and the science camera, chief mission engineer Marc Rayman
said the project team devised a method of keeping the spacecraft
properly oriented by keeping a small number of stars centered in the
camera. One set of stars, dubbed "thrustars", will be used while the
spacecraft uses its ion engine to make sure it remains on course,
while the other set, called "Earthstars", will be used when the
spacecraft has to orient its main antenna to points towards the Earth,
315 million kilometers (195 million miles) away.
On June 21, DS1's ion engine was powered up for the first time
since the star tracker failure last November for a brief test of the
new star tracker system. After several other tests, the engine was
turned on again June 28, this time to maximum power for a one-week
test.
Project officials will analyze the data after the test is
completed this week to determine how well the spacecraft maintained
its orientation during the thruster burn. If the data checks out,
Rayman said they will resume thrusting in a few days.
The recovery comes just in time for the spacecraft to begin
maneuvering towards a September 2001 flyby of comet Borrelly. DS1
needed to start its ion engine this month in order to make the flyby,
one of two originally planned when DS1 began its extended mission last
fall. A January 2001 flyby of comet Wilson-Harrington will not happen
because of the time lost to the star tracker failure.
"The entire undertaking has been one of the most challenging
yet one of the most successful and impressive robotic space rescues
ever accomplished," Rayman said in a statement late Tuesday. "A great
deal of difficult work lies ahead, but providing DS1 with a new lease
on life represents an outstanding achievement in NASA's efforts to
extend humankind's reach into the cosmos."
DS1, launched in October 1998, was primarily designed to test
a suite of a dozen advanced technologies intended for future missions,
ranging from its ion drive to an autonomous computer control system.
Ironically, DS1's star tracker, while of an advanced design, was not
among those dozen technologies the spacecraft was to test.
DS1 successfully tested all of those advanced technologies
last year and wrapped up its primary mission with a flyby of asteroid
9969 Braille last July. The spacecraft has been in an extended
mission since last September.
China Planning October Launch of Shenzhou 2
China is reportedly planning another test flight of a
spacecraft designed to carry humans later this year, Hong Kong
newspapers reported this week.
The newspaper Wen Wei Po reported July 4 that the Chinese
government was planning a launch of an upgraded version of the
Shenzhou spacecraft in the near future. That launch is not imminent,
but will likely occur by October, according to the newspaper Mingpao.
The spacecraft, named Shenzhou 2, is an upgraded version of
the Shenzhou spacecraft launched last November that spent a day in
orbit before landing back in China. Wen Wei Po said changes in wiring
reduced the mass of the spacecraft by about 100 kilograms (220 pounds)
and also made the wires less vulnerable to damage.
The reports indicated no other major changes to the design of
the Shenzhou spacecraft, which is superficially similar to Russia's
Soyuz spacecraft. While some Russians claimed to have provided
technical support for Shenzhou, Chinese officials have maintained that
the spacecraft was designed and developed without outside assistance.
While this second test flight is also likely to be unmanned,
Western observers expect China to follow this flight with a manned
spaceflight, making China the third country after the United States
and the former Soviet Union to send humans into orbit.
A report issued late last month by the U.S. Defense Department
concluded that China will try a manned launch some time next year.
"Although nearly all major aspects of China's manned space program
began within the last five years or so, Beijing is still aiming for a
possible first manned launch by 2001," the report noted.
Such a flight, the report's authors claimed, would have
political and military implications. "While one of the strongest
motivations for this program appears to be political prestige, China's
manned space efforts could contribute to improved military space
systems in the 2010-2020 time frame," the report said.
NASA Denies Computer Attack Endangered Shuttle Mission
NASA officials strongly denied a British report Monday that an
attack on NASA's computer systems endangered a shuttle mission in
1997.
The denial comes in the wake of a British Broadcasting
Corporation (BBC) documentary aired Monday night that quoted NASA
officials who said that an attack on a shuttle communications systems
compromised shuttle safety during the STS-86 shuttle mission to the
Russian space station Mir in September 1997.
During that flight, the BBC documentary claimed, hackers broke
into a NASA computer system that monitors medical data about the
shuttle crew. That attack, the report claimed, overloaded
communications systems between the shuttle and the ground and forced
NASA to communicate with the shuttle crew through Mir.
"We had an activity at a NASA center where a hacker was
overloading our systems...to such an extent that it interfered with
communications between the NASA center, some medical communications
and the astronauts aboard the shuttle," Roberta Gross, NASA inspector
general, told the BBC in the documentary.
However, NASA said in a statement issued late Monday that
while a computer attack did take place, it was far less severe than
what the BBC complained. "NASA's Inspector General's office found
that during the STS-86 mission in September of 1997, the transmission
of routine medical information was slightly delayed due to a computer
hacker," the statement noted. "However, the transmission was
successfully completed."
"At no time was communication between NASA and the astronauts
compromised," the space agency added. "The communication interruption
occurred between internal ground-based computer systems."
Even Gross's statement in the BBC documentary downplayed the
severity of the attack. "Well, NASA has a lot of fail-safes and it
makes sure that there's not just one way of communicating, so the
transmission ultimately went through," she said.
NASA, as one of the highest-profile U.S. government agencies,
is subject to more than its share of attempts to break into its
computer systems. The BBC documentary said NASA recorded a half-
million computer attacks just within the last year.
None of those attacks, though, have threatened mission-
critical computer systems that handle the shuttle or the International
Space Station, the space agency's statement claimed. "There has never
been an interruption of communication service with the Shuttle due to
computer hacker attacks. The command and control communications links
between Mission Control and a space shuttle in orbit are extremely
well insulated."
NEAR Shoemaker Edges Closer to Eros
A successful thruster burn Friday sent NASA's NEAR Shoemaker
spacecraft on its closest approach yet to the near-Earth asteroid
Eros.
A 20-second engine burn at 2 pm EDT (1800 UT) Friday afternoon
shifted NEAR Shoemaker from a circular 50-km (31-mi.) orbit around
Eros into an elliptical one that carries the spacecraft between 50 and
35 km (31 and 22 mi.) from the center of Eros.
Because of Eros' oblong shape, the new orbit actually bring
the spacecraft as close as 19 km (12 mi.) from the ends of the
asteroid. However, after nearly five months in orbit around the
asteroid spacecraft controllers are confident that this low orbit is
perfectly safe for the spacecraft.
"Now that we have a better read on the asteroid, our ability
to predict where we're going is much better than it was earlier in the
mission," said Bobby Williams, head of the spacecraft navigation team.
The maneuver was the first for NEAR since April 30. A second
maneuver on July 14 will circularize the spacecraft's orbit at an
altitude of 35 km. The spacecraft will then spend ten days in this
low orbit, mapping the asteroid's gravity field while also collecting
high-resolution images and spectral data of the asteroid's surface.
A pair of maneuvers on July 24 and 31 will reverse the
process, bringing NEAR Shoemaker back out into a 50-km orbit. Another
pair of maneuvers in late August and early September will bring the
spacecraft even farther away from Eros, where it will conduct global
mapping of the asteroid from a 100-km (62-mi.) orbit.
This month's close orbit may not be closest the Discovery-
class spacecraft ever comes to Eros. When NEAR entered orbit around
Eros in February, mission officials said they were planning to bring
the spacecraft very close -- within a few kilometers -- of the
asteroid by the end of the year or the beginning of next year, and may
end the mission next year by landing the spacecraft on the asteroid
itself.
Laser and Microwave Sails Move Closer to Reality
A piece of science fiction has moved closer to science fact
with the recent successful laboratory tests of sails propelled by
lasers and microwaves.
In separate tests, scientists were able to move lightweight
sails using nothing more than a beam of microwaves or a laser, a
technology that could be used in coming decades for interplanetary or
even interstellar spacecraft.
In one test, a laser beam pushed horizontally a thin piece of
carbon-carbon microtruss fabric, a specially-designed lightweight but
strong material capable of withstanding high temperatures. In the
other test, a beam of microwaves accelerated a similar piece of fabric
off the ground a short distance.
"Accelerations of several times the force of gravity were
observed during the microwave tests," said Dr. James Benford,
president of Microwave Sciences, Inc. in Lafayette, CA. "In one case,
the sail flew two feet in response to the high acceleration."
The laser test, conducted at Wright-Patterson Air Force Base
in Ohio, and the microwave test, conducted at JPL, are believed to be
the first successful attempts to propel a sail in such a manner.
"These are really two giant steps forward," said Henry Harris,
task manager for the microwave levitation and laser experiments at
JPL. "These results would not have been possible without newly
developed ultralight, high-temperature sail materials and beamed-
energy propulsion methods."
"These experiments are the first known measurements of laser
photon thrust performance using lightweight sails that are candidates
for spaceflight," said Leik Myrabo, a professor at Rensselaer
Polytechnic Institute who led the laser-propulsion work.
Laser- and microwave-propelled sails, like solar sails, don't
require any propellant, relying instead on the force imparted to the
sails by photons that collide with it. While that force may be much
smaller than what a conventional rocket engine can provide, it is
continuous, allowing the spacecraft to slowly accelerate to speeds
that would either not be possible with conventional engines or would
require spacecraft that were much heavier and difficult to build.
A disadvantage of a beamed-propulsion spacecraft is that they
require potentially huge amounts of energy to generate even small
amounts of thrust: baseline proposals for such spacecraft call for
hundreds of megawatts to gigawatts of laser of microwave power. By
comparison, the recent laboratory tests used about 10 kilowatts of
laser or microwave power.
However, that high power, focused on the spacecraft, would
permit acceleration of the spacecraft over far longer periods of time
than would be possible with a solar sail, whose thrust would drop off
as the sail traveled farther from the Sun. This makes beamed-
propulsion spacecraft a leading candidate for eventual interstellar
missions, albeit decades in the future.
Interestingly, while beamed propulsion could make interstellar
flight -- so common in science fiction -- a reality, several science
fiction authors are playing major role in developing beamed
propulsion. The concept of laser- and microwave-propelled sails was
first proposed in papers by futurist and science fiction author Robert
Forward in the mid 1980s. Another science fiction author, Gregory
Benford, worked on the theory of microwave propulsion with his brother
James, who led the microwave beam experiment at JPL. And that
microwave-propulsion experiment grew out of a report on laser and
microwave propulsion by another science fiction writer, Geoffrey
Landis of the Ohio Aerospace Institute.
Cluster Space Science Mission Moves Closer to Launch
The European Space Agency approved late last month the mid-
July launch of the first two of four Cluster II space science
satellites.
A Cluster II Flight Readiness Review on June 23 cleared the
way for the launch of the first two Cluster II satellites on a Soyuz
rocket from Baikonur, Kazakhstan. Launch is scheduled for 8:40 am EDT
(1240 UT) July 15, at the beginning of a six-minute launch window.
ESA had hoped to launch the Cluster satellites on July 12, but
that would have conflicted with the Proton launch of the Zvezda
service module for the International Space Station, also scheduled to
take place July 12 at Baikonur. Since Baikonur could not support both
launches on the same day, and because the space station launch carried
a higher precedence, the Cluster launch was delayed.
A second Soyuz launch is planned for August 9 to launch the
second pair of Cluster satellites. Both launches will use the new
Fregat upper stage on the Soyuz, which was flown for the first time
earlier this year in a pair of test launches.
ESA had hoped to launch the Cluster II satellites a month
earlier, but shipment of the satellites to Baikonur was delayed in
April when attitude control thrusters on the spacecraft were found to
leak small amounts of propellant. That problem also delayed the
launch of several commercial communications satellites that used
similar thrusters from the same manufacturer, DaimlerChrysler
Aerospace subsidiary Dornier Satellitensysteme.
Once launched, the four Cluster II satellites will be placed
into elliptical orbits ranging between 25,000 and 125,000 km (15,500
and 77,400 mi.) above the Earth. Flying in formation, the four
satellites will perform a three-dimensional study of the interaction
between the solar wind and the Earth's magnetic field.
The four satellites are functionally identical to the original
four Cluster satellites, which were lost when the Ariane 5 booster
they were on veered out of control and was destroyed less than a
minute after launch on its maiden flight in June 1996.
The four Cluster II satellites are currently only known by
their designations, FM5 through FM8 (FM1 through FM4 were assigned to
the original Cluster satellites.) That will change in mid-July, when
ESA officials announce the winner of a public contest to name the four
spacecraft.
Fifteen semifinalists, one from each ESA member nation, were
recently announced by the space agency. The proposed names range from
"Flute, Violin, Cello, Piano" to "Tango, Rumba, Salsa, Samba".
British Rocket Takes a Step Towards the X Prize
A British company took a small but successful step towards
winning the $10 million X Prize with a successful rocket flight
Thursday.
Starchaser Industries, a small company based in Cheshire,
U.K., successfully flew its two-stage Starchaser-Discovery rocket to
an altitude of 5,750 meters (19,000 feet) from Morecambe Bay, U.K.
Thursday morning.
Solid-fuel motors accelerated the rocket from zero to 1,130
kmph (700 mph) in the first three seconds after liftoff, at which
point the first stage separated. The second stage then fired and
carried its payload, a small pod, to the peak altitude before
parachuting back to Earth.
"Everything went absolutely as planned," said Steven Bennett,
CEO of Starchaser Industries, who has been launching small rockets
since 1993. "We saw a perfect separation and return of the rocket."
The six-meter (20-foot) rocket, described as the largest
reusable research rocket ever built in Europe, is itself not intended
to fly into space, but instead test an escape rocket that will be used
on Thunderbird, the reusable suborbital rocket that Starchaser is
developing.
The Thunderbird would feature a large single-stage rocket
booster using liquid oxygen and kerosene propellants. It would carry
a payload module, capable of holding up to three people, to an
altitude of at least 100 km (62 miles) before parachuting back to
Earth.
With this successful test, Bennett believes that his company
is on track to compete for the X Prize as soon as next year. "I am
very optimistic that we will launch our first piloted rocket by the
end of 2001," he said. The Thunderbird could be carrying passengers
by mid-2003 if those flights are a success.
Not revealed, though, is either the estimated cost of
developing and building Thunderbird and how much funding the company
needs to meet those costs.
At stake for Starchaser is the $10 million X Prize. First
announced in the mid-1990s, the prize will be awarded to the team that
develops a reusable rocket -- without government support -- that can
carry three people to an altitude of at least 100 km twice in a two-
week period. Such a prize, organizers believe, will help stimulate
interest in space tourism and other applications of suborbital
reusable spacecraft.
Seventeen teams, including Starchaser, are competing for the X
Prize. While the $10-million prize is not yet fully funded, X Prize
chairman Peter Diamandis said at a space tourism conference in
Washington last month that the X Prize Foundation is in negotiations
to raise the remainder of the prize money.
SpaceViews Event Horizon
July 12 Proton launch of the Zvezda service module for the
International Space Station, from Baikonur,
Kazakhstan at 12:56 am EDT (0456 UT).
July 14 Atlas 2AS launch of the EchoStar-6 direct broadcasting
satellite, from Cape Canaveral, Florida at 1:21 am
EDT (0521 UT)
July 15 Kosmos-3M launch of the CHAMP microsatellte payload
from Plesetsk, Russia at 8:00 am EDT (1200 UT)
July 15 Soyuz launch of the first two cluster 2 solar science
satellite from Baikonur, Kazakhstan at 8:40 am EDT
(1240 UT).
July 16 Delta 2 launch of the GPS 2R-5 satellite from Cape
Canaveral, Florida at 5:17 am EDT (0917 UT)
July 20-21 Second Annual Lunar Development Conference, Las Vegas,
Nevada
August 10-13 Third International Mars Society Convention, Toronto,
Ontario
Other News
Cosmic Searchlight: New Hubble Space Telescope images of galaxy M87
have given astronomers one of their best views yet of a jet of
material that gives the elliptical galaxy the appearance of a "cosmic
searchlight". The image, released Thursday as part of the Hubble
Heritage Project, reveals what appears to be a bright blue beam of
light coming out of the center of the elliptical galaxy, 50 million
light-years from the Earth. That beam is actually a jet of electrons
and other subatomic particles moving at nearly the speed of light.
Astronomers believe the jet is powered by a black hole at the center
of the galaxy: twisted magnetic field lines accelerate hot gas and
dust surrounding the black hole into a thin jet seen by Hubble.
Thank Our Lucky Stars: If the physics of stars was a little different
in our universe, life as we know it could not exist, European
scientists concluded in a paper published in the journal Science last
week. A four-percent change in the strong nuclear force which binds
protons and neutrons, or just a half-percent change in the Coulomb
force that repels protons from one another, would have kept stars from
forming carbon and oxygen, two of the basic building blocks of life.
These elements are made in stars near the near of their lives, as they
enter a red giant phase and resort to fusing helium rather than
hydrogen. "I am not a religious person, but I could say this universe
is designed very well for the existence of life," Heinz Oberhummer of
the University of Vienna, one of the coauthors of the Science paper,
told SPACE.com.
Satellite Black Box: British scientists are beginning work on the
spacecraft equivalent of an airplane's flight data recorder, better
known as a "black box." The 0.5-kg (1.1-lb.) recorder would not
monitor the spacecraft itself so much as keep tabs on the space
weather conditions around the spacecraft at the time of a spacecraft
failure. Solar flares and other space weather phenomena have been
linked to the failures of some spacecraft, but without conclusive
evidence. "The fear is that these could be a dominant cause of on-
orbit failure," Andrew Coates of the Mullard Space Science Laboratory
told the BBC.
Mixed News for Orbital: Orbital Sciences Corporation reported nearly
a quarter-billion dollars in new orders in the first half of 2000, but
an affiliate company has run into some financial problems. Orbital
said Thursday it won $725 million in new orders in the first six
months of 2000, raising its backlog of firm orders to $2.1 billion, a
figure that rises to $5 billion if contract options are included.
That news comes after ORBCOMM, a company partially owned by Orbital,
said it was laying off 20 percent of its work force to "streamline"
its organization and cut costs. The streamlining also means Orbital
will stop production of additional ORBCOMM satellites, although it
will continue to operate its existing constellation of low-Earth orbit
communications satellites, despite some early press reports to the
contrary.
An Astronomical Accounting Error: A simple error in a NASA financial
report was enough for the space agency to incur the wrath of a key
member of Congress. Rep. James Sensenbrenner (R-WI), chairman of the
House Science Committee, lambasted NASA Thursday for a $590-million
error in its 1999 Financial Accountability Report. While NASA
officials passed off the error as a reporting error that got past both
their staff and auditors at Arthur Andersen, and not an indication of
misspent funds, that answer wasn't satisfactory for Sensenbrenner.
"I'm deeply disappointed that the agency that could send a man to the
moon now can't even balance its books to the nearest half-billion," he
said in a statement. "Inattention to details such as using English or
metric units, or making $590-million accounting errors, indicate
significant management problems continue to bedevil NASA."
*** Letters ***
Letters to the Editor: Galileo and Space Tourism
Editor's Note: The article in last week's issue of SpaceViews about
plans to eventually end Galileo's mission as well as the feature story
about space tourism generated a large amount of reader response. A
selection of the letters we received are included below. Letters to
the editor can be sent to letters@spaceviews.com.
Hopefully I'm not the only person that was greatly
disappointed by the decision to throw away millions of dollars by
scuttling the Compton because the odds of 'some amount' of property
damage increased to just slightly better than those of actually seeing
God through a ground based telescope. Now, NASA and 'COMPLEX' are
posturing themselves over the delete key for the Galileo, which has
been a spectacular craft performing like a true hero, well beyond it's
initial planned mission. It has beamed back to Earth a magnitude more
data after its proposed mission than during, and continues to perform
for its controllers, and continues to thrill scientists and school
children alike with its incredible discoveries within the Jovian
system. Now, it's my belief that it was paid for by the taxpayers of
this country, and not a small group of people in a little room
somewhere doing nothing more profound than inventing clever, powerful
sounding names for themselves, so here's what I'd like to suggest --
the people who paid for it, are the people who own it, and the people
who own it should get to decide, by means of a vote, what to do with
it, and to that end I'd like to make a suggestion.
I think we should let it fly a few more 'not so risky'
missions, then swing it around and get it headed back home! The data
that could be compiled by studying it, and its components, would give
designers and builders of future space vehicles and habitats an
enormous leap in the science of space structures and aging, possibly
bypassing an entire generation of trial and error growth.
As far as the risk of contaminating Europa, I have these
thoughts to share: How many microorganisms, from Earth, do you think
hitched a ride aboard the Galileo, and more importantly, how many of
those do you suspect could still possibly be surviving after the time,
the harsh temperatures, and the intense radiation encountered during
the Io fly-bys. I'll bet the odds of any surviving speck of self
replicating chemical chain onboard the Galileo are even less than the
odds of finding life under Europa's icy shell, and I'm not a
statistician, but common sense says those odds, joined together with
the odds of losing control of the Galileo, and the odds of an out of
control Galileo crashing into an icy speck in the heavens called
Europa, have got to be approaching zero. Now let's ask ourselves if
we want to take those odds and scuttle the Galileo, or bring it home
and display it in the Smithsonian, like the true hero it is!
Dan Hyatt
[Editor's Note: while an interesting suggestion, such a return is
almost certainly impossible given Galileo's limited propellant and
Jupiter's powerful gravity.]
While this thought is not unique to me, I thought some
coverage of how space tourist competition sparked by Mir and Mr. Tito
might spur NASA and the regulators to develop a functioning U.S.-based
space tourism program, rather then let the money go to Russia,
especially since NASA wants Mir to fall down. Of course, we would
need a habitable orbiting satellite for that, but ...
Maybe competition will work when regulation goes nowhere. It
has been how long since Apollo? How many more generations must wait
until the regulators get all their ducks in a row, and the insurance
companies conclude that the risk of space flight is less than the risk
of taking the A Train in New York?
Elliot
We need Hollywood again. What is missing is a realistic movie
on space tourism. The best vehicle would probably be a romantic
comedy. This type of plot line could have the tourism as very
realistic but the "love interest" would be the main mover. Just as in
James Cameron's Titanic, the ship/situation would be the backdrop. I
chose the comedy genre because there is an area where the plot could
use the "giggle factor" to debunk the fear of space travel-just like
jujitsu.
The best director for this project would be Ron Howard. He
has the most experience in shooting in microgravity (Apollo 13). The
best producer would be Tom Hanks since he's a confirmed space
enthusiast.
Destination Moon inspired the American people that the moon
was not just idle dreaming. If not for that film, I believe that
JFK's "moon in this decade" speech would have collapsed as fast as
Bush's $450-billion Mars program.
Stellar Bear
========
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