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标 题: SpaceViews -- 2000 September 18(转载)
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【 原文由 hitsma@0451.com 所发表 】
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S P A C E V I E W S
Issue 2000.38
2000 September 18
http://www.spaceviews.com/2000/0918/
*** News ***
Shuttle Crew Completes Work at Space Station
NASA Halts Work on Pluto Mission
Ariane 5 Launches Two Communication Satellites
NBC to Air Mir TV Show
British Government to Release Report on Impact Threat
Discovery Rolled Out to Launch Pad
Committee Issues Recommendations for Future ESA Missions
Superoxides May Keep Martian Surface Sterile
ORBCOMM Files for Bankruptcy Protection
SpaceViews Event Horizon
Other News
*** Articles ***
Recalling Drake's Voyages
Editor's Note: Starting with this issue we are switching to a new
mailserver to distribute our issues. The only change you should
notice -- other than perhaps a speedier delivery of each issue -- is a
new address for subscriptions and unsubscriptions. Instead of
majordomo@spaceviews.com or majordomo@seds.org, please use
listserv@listserv.space.com. See the end of this issue for full
details on how to (un)subscribe.
- Jeff Foust, Editor
jeff@spaceviews.com
*** News ***
Shuttle Crew Completes Work at Space Station
The space shuttle Atlantis undocked from the International
Space Station late Sunday night, its crew having wrapped up a mission
to prepare the station for its first long-term crew.
The shuttle undocked from the station at 11:46 pm EDT Sunday
night (0346 UT Monday) as the spacecraft passed over Ukraine. The
undocking took place two minutes later than planned as the shuttle
crew waited for a computer used during the procedure to reboot.
However, the undocking took place well within a 13-minute window when
the station was in range of Russian ground stations.
After pulling away to a distance of about 135 meters (450
feet), shuttle pilot Scott Altman performed a double loop around the
station as other members of the STS-106 crew took photos and video of
the station to document it in its current configuration. The shuttle
then pulled away from the station for good.
The undocking came after the crew spent over five days working
within the station, one day longer than originally planned,
transfering over 3,000 kg (6,600 lbs.) of supplies and equipment into
the station from both the shuttle and a Progress spacecraft that
docked with the Zvezda service module last month. The seven-man crew
installed on the station eveything from food and water to the
station's toilet and exercise treadmill. They also transfered trash
back into the Progress, which will be automatically undocked and
deorbited in a few weeks' time.
The crew also installed three batteries in the Zvezda module
and replaced two batteries in Zarya. Zvezda was launched with only
five of its eight batteries in place as a weight-saving measure;
however, the crew was unable to get one of the three batteries they
installed to work. Troubleshooting of the faulty battery will be left
to Expedition One, the station's first long-term crew, as NASA
officials noted that the module can operate normally with as few as
five batteries.
While the shuttle was docked with the station the orbiter used
its thrusters on four occasions to raise the station's orbit. The
four maneuvers raised the station's average altitude by 22.5 km (14
mi.) to 388 by 375 km (240 by 232 mi.)
During a press conference after the undocking, the crew spoke
highly of the station, saying it is in excellent shape for Expedition
One, scheduled to arrive at ISS in early November. "The air quality
[within ISS] is wonderful," said shuttle commander Terry Wilcutt.
"The noise level is about the same as the shuttle."
"We laid out the red carpet for the first crew to come aboard,"
said Bob Cabana, manager of international operations for the
International Space Station Program.
During the mission the crew often became mechanics and luggage
porters as they moved supplies into the station and installed and
repaired equipment within it, tasks which mission specialist Dan
Burbank said the crew didn't seem to mind. "I think it's going to
take a lot of different skills" to assemble the station, he said.
The crew will spend their remaining time in orbit packing up
equipment within the shuttle and preparing for their return to the
Kennedy Space Center in Florida, currently scheduled for Wednesday at
3:56 am EDT (0756 UT).
NASA Halts Work on Pluto Mission
A key NASA official confirmed Wednesday that the space agency
has stopped work on a mission to Pluto, a decision that some say
effectively cancels the proposed mission to the outermost planet.
Ed Weiler, NASA associate administrator for space science,
said at a Congressional hearing Wednesday afternoon that escalating
costs have forced the agency to suspend work on the Pluto/Kuiper
Express (PKE) and focus instead on the planned Europa Orbiter (EO)
mission.
Weiler said the agency filed a "stop work" order for PKE on
Tuesday, bringing to a halt work on the current mission concept whose
missions costs Weiler claimed were spiraling out of control.
"When I became the associate administrator two years ago, I
was given a Pluto and Europa program, and the estimate for those two
programs through completion... was about $700 million," Weiler told
the space subcommittee of the House Science Committee. "We went from
that point two years ago to today where the current estimates from the
Jet Propulsion Lab for these missions have doubled."
A mission to Europa that would look for evidence of liquid
water ocean that could harbor life has a higher priority than one to
Pluto, Weiler said, so he made the decision to stop work on PKE and
focus on Europa Orbiter. Making that decision now, he said, saves
"upwards of a million dollars a week" that would have been spent on
Pluto mission in the next fiscal year, which begins October 1.
"Basically, I directed the project to go full speed on Europa
to give us the earliest possible launch of that mission, and spend the
remaining money -- and there is significant money remaining -- on
reformatting, reformulating the program," Weiler said.
PKE is one of three missions the space agency planned as part
of its Outer Planets/Solar Probe, or "Ice and Fire", missions, along
with the Europa Orbiter and Solar Probe. Under original plans EO was
to launch in 2003 and PKE, using many of the same spacecraft
subsystems as EO, a year later.
Weiler denied, however, that he had cancelled a Pluto mission
outright. "I did not cancel Pluto," he said. "Pluto is greatly
deferred. We will still do a Pluto mission, the question is when and
what Pluto mission we will do."
Under the mission plan in place before the stop order, the PKE
spacecraft would have been launched in 2004, and, after a Jupiter
flyby, would arrive at Pluto in 2012. Weiler said he has asked JPL to
look at the technologies necessary to get to Pluto before 2020.
Weiler hinted that there would be a focus on space propulsion
technologies that would shorten the travel time of a Pluto mission;
however, if the Pluto mission is delayed by more than a couple years,
it loses the opportunity to do a Jupiter flyby to gain speed.
"Certainly after 2006, I believe, we miss the deadline [for a
Jupiter flyby] and miss the opportunity for many, many years down the
road," he admitted. "But all that taken into consideration, I still
believe that Europa is a higher priority mission."
While Weiler said the mission has not been cancelled, those in
scientific and space activist communities argue that the decision to
stop work on the mission is effectively a cancellation. "NASA says
that the cancellation of the mission is part of a restructuring of the
outer planets program and that Pluto exploration remains a goal," The
Planetary Society said in a statement. "But, pushed out to the
indefinite future, it is hardly a meaningful goal."
There has been speculation for several months that PKE was in
jeopardy because of growing costs for it and other space science
programs. Carl Pilcher, director of solar system exploration at NASA
Headquarters, wrote in a "Dear Colleague" letter last month that the
mission was in "serious jeopardy".
A Pluto mission has strong support in the planetary science
community. A 1998 report by the Committee for Planetary Exploration
(COMPLEX) of the National Research Council recommended a spacecraft
mission to Pluto and its moon Charon, a recommendation endorsed by
another COMPLEX report issued earlier this year.
"The highest scientific priority for the exploration of the
trans-neptunian solar system is extensive and detailed measurement of
the fundamental physical and chemical properties of the Pluto-Charon
system," the report noted. "Because Pluto and Charon are barely
spatially resolvable from Earth, many of the relevant properties can
be measured only by a robotic spacecraft."
While Weiler said that a Europa mission was a higher priority
than PKE, a Pluto mission arguably is more time-sensitive than one to
Europa. In addition to the limited window for a Jupiter flyby, Pluto
itself is changing as it moves farther from the Sun in its elliptical
orbit. As the planet cools, some planetary scientists believe that
the planet's tenuous atmosphere may collapse, freezing onto its
surface. When that happens, scientists will lose the opportunity to
study the planet's atmosphere for perhaps more than 200 years.
Ariane 5 Launches Two Communication Satellites
A long-delayed Ariane 5 booster successfully launched a pair
of American and European communications satellites Thursday night, the
second launch in as many weeks for Arianespace.
The Ariane 5, officially known as Ariane 506, lifted off on
Flight 130 on schedule at 6:54 pm EDT (2254 UT) September 14 from the
ELA 3 launch complex at Kourou, French Guiana. Its payload, the Astra
2B and GE-7 communications satellites, were placed into a
geosynchronous transfer orbit and separated from the launcher 37
minutes after liftoff.
Flight 130 was originally scheduled for launch in May, but was
delayed a month before to investigate a possible problem with attitude
control thrusters on the Astra 2B satellite. Those checks also
affected a number of other satellites using the German-built
thrusters, including the four Cluster II space science satellites for
ESA and the Eutelsat W4 communications satellite.
The launch was rescheduled for late July, but delayed again to
check the attitude control system of the Ariane 5 itself, after
engineers ran into problems with a similar system being used on a new
Ariane 5 upper stage under development.
Astra 2B, based on the Eurostar family of communications
satellite built by Astrium, will be positioned in geosynchronous orbit
at 28.2 degrees east longitude. The 3,300-kg (7,260-lb.) satellite
will be used by Luxembourg-based Societe Europenne des Satellites (SES)
to provide digital television, radio, and Internet services using its
28 Ku-band transponders.
GE-7, based on the A2100 family of communications satellite
built by Lockheed Martin, will be placed at 137 degrees west
longitude. The satellite, intended to replace the existing Satcom C1
spacecraft, will provide cable and broadcast television, radio, and
data services for all 50 U.S. states plus Mexico and the Caribbean,
using 24 C-band transponders.
The launch was the seventh of the year for Arianespace, and
the second for the Ariane 5. The launch was also the second in as
many weeks for Arianespace, after the September 6 launch of the
Eutelsat W1 communications satellite on an Ariane 4.
Arianespace had planned to try a third mission this month with
a September 27 launch of an Ariane 4 carrying the Europe*Star FM1
communications satellite, but that launch has since slipped to early
October.
NBC to Air Mir TV Show
The NBC television network has agreed to air a "reality TV"
show where the winner will be sent to the Mir space station, the
entertainment newspaper Daily Variety reported Wednesday.
The network will pay $35-40 million for the rights to
"Destination Mir", a program that will be produced by Mark Burnett,
producer of the smash summer hit "Survivor" on CBS. That cost
includes a $20 million fee to MirCorp, the company leasing Mir for
commercial uses, to send the show's winner to the space station.
The show will be similar to Survivor, with a dozen ordinary
Americans picked to begin cosmonaut training at Star City, the Russian
space center outside of Moscow. One member of the group will be
kicked out at the end of each episode by training officials until a
small group of finalists remain. The finalists will then meet at the
Baikonur launch site in Kazakhstan, where the winner will be announced
on a live broadcast and almost immediately launched to Mir for a 10-
day visit.
Burnett revealed last month that he had reached an agreement
with MirCorp to send the winner of the show to Mir, provided a network
decided to purchase the show. The company has reportedly agreed to a
reserve a spot for the winner of the show on a flight between December
2001 and June 2002.
Variety reported that all four major television networks in
the U.S. -- ABC, CBS, Fox, and NBC -- had expressed interest in the
show, but that only NBC was willing to both pay for the rights to the
show and agree to a profit-sharing deal with Burnett for advertising
that will air during the show. NBC also agreed to air a one-hour
documentary Burnett is producing about Dennis Tito, the American
millionaire who will be the first "citizen explorer", or space
tourist, to visit Mir next year.
In an interview with Variety, Burnett spoke highly of MirCorp
and about space commercialization in general. "Part of my goal is to
be actively involved, as I get older, with Mir and the privatization
effort," he told the newspaper. "These people are serious. They're
meeting with hotel chains. People are starting to realize space isn't
that far away."
"The reason I got excited about this was that I know this is
the ultimate project for Mark," Garth Ancier, president of NBC
Entertainment, told Variety. "This was a project where his eyes lit
up."
Executives with MirCorp have in the past emphasized the role
Mir could play in entertainment and related fields in addition to
tourism and conventional space-related businesses. "I am particularly
pleased that the media and entertainment aspects of MirCorp's business
model are coming to life," Jeffrey Manber, president of MirCorp, said
last month when the initial deal between the company and Burnett was
announced. "This interest bodes particularly well for our Internet
initiative and the other ventures we are pursuing."
MirCorp has announced two manned missions to Mir in the first
half of next year. Two Russian cosmonauts will be launched to the
station early next year, after the launch this fall of an unmanned
cargo spacecraft. In mid-2001 a second crew of two Russians plus Tito
will be launched to the station. Tito will return to Earth 10 days
after launch with the first Mir crew while the second crew remains on
the station into the second half of the year. The company has not
announced any specific plans for flights beyond that, with the
exception of accommodating the winner of the television show on a
future flight.
MirCorp has already operated what it called the first private
human spaceflight mission ever, when two Russian cosmonauts flew to
Mir in April and remained on the station for 73 days, reviving the
station after seven months of dormancy and confirming the station was
still in good condition.
British Government to Release Report on Impact Threat
The British government is expected to release a report Monday
that will recommend that it spend several million dollars a year on
programs to look for near-Earth objects that could pose an impact risk
to the Earth.
The report is the result of several months' of work by the
Task Force on Near-Earth Objects (NEOs), a three-person group created
in January by the British government to look into the threat such
objects pose to the Earth and what role the UK should take to mitigate
that threat.
The task force will reportedly conclude that the cost to
Britain of doing nothing is on the order of 120 million pounds (US$192
million) a year. That figure is based on the damage a one-kilometer
(0.6-mile) asteroid colliding with the Earth once every 100,000 years
would do.
"The risk of asteroidal or cometary impacts substantially
exceeds the limits of tolerability applied by the Health and Safety
Executive to the nuclear power industry and the transport of hazardous
goods," Spaceguard UK, a British organization that supports expanded
NEOs searches, noted in a statement.
The report will recommend that the government spend a small
fraction of this cost -- less than three percent -- on efforts to
reduce the threat of such an impact. This work includes telescopic
surveys of NEOs, studies of their physical properties, and public
education about NEOs.
The report culminates several years of lobbying of the British
government by Spaceguard UK to become more involved in the search for
NEOs, an effort to date that has been dominated by the United States.
They have also received support from Lembit Opik, a member of the
British Parliament.
The three-person Task Force is chaired by Harry Atkinson, the
former head of Britain's Science and Engineering Research Center who
also served as chairman of the European Space Agency's Council.
The two other members of the committee are Crispin Tickell,
chancellor of the University of Kent and a former British ambassador
to the UN who has been active on environmental issues; and David
Williams, an astronomy professor at University College London.
Lord Sainsbury, the British science minister, received a copy
of the report in August via the British National Space Center, the
UK's space agency. The report will be released on the web at the site
http://www.nearearthobjects.co.uk/.
Discovery Rolled Out to Launch Pad
As one member of the shuttle fleet circled the globe, another
orbiter was rolled out to its launch pad early Monday for a mission
scheduled for launch next month.
The shuttle Discovery was rolled out to Pad 39A early Monday,
leaving the Vehicle Assembly Building (VAB) at the Kennedy Space
Center around 2 am EDT (0600 UT) and arriving at the launch site 6
hours and 15 minutes later.
The shuttle is scheduled to launch on mission STS-92 on
October 5 at around 9:30 pm EDT (0130 UT October 6). The primary
purpose of the 11-day mission, known as Flight 3A in the ISS assembly
schedule, will be to install on the Unity module the "Z1" section of
the station's external truss structure, a framework that will be
attach a set of solar panels to during the STS-97 mission about two
months later.
The structure also features a Ku-band antenna to support
television broadcasts from the station as well as gyros that will be
used in the future to provide attitude control for the station. The
mission will also install the Pressurized Mating Adapter - 3, a new
docking port on the Unity module that the shuttle will use on future
flights to the station. Several spacewalks are planned to complete
all the assembly tasks of the mission.
STS-92 features a seven-person crew commanded by Brian Duffy,
with rookie astronaut Pamela Melroy as pilot. Leroy Chiao, Peter
Wisoff, Michael Lopez-Algeria, William McArthur, and Japanese
astronaut Koichi Wakata will be mission specialists on the flight.
The rollout of the orbiter, attached to its external fuel tank
and solid-propellent boosters, took place at the same time two members
of the crew of STS-106 were performing a spacewalk outside the
International Space Station, to which the shuttle Atlantis is
presently docked.
NASA had considered rolling out Discovery prior to the
September 8 launch of Atlantis, but decided to keep the orbiter in the
VAB so that if a hurricane approached Cape Canaveral, only one orbiter
would have to be pulled back to the safety of the assembly building.
NASA very nearly decided to do that over the weekend as Hurricane
Gordon approached the Florida coast, but elected to keep Discovery
on the pad as the hurricane stayed north of the space center.
STS-92 represents a historic milestone for NASA, since it will
be the 100th mission of the shuttle program, dating back to the first
shuttle mission, STS-1, in April 1981. The mission will also the be
the last to the station before the era of permanent occupation of the
orbiting facility begins: the first long-term crew is scheduled to
arrive at ISS in early November, just a few weeks after the STS-92
mission.
Committee Issues Recommendations for Future ESA Missions
A European Space Agency (ESA) committee recommended last week
that the agency pursue a suite of planetary and space science missions
in a decade's time, ranging from a Mercury orbiter and lander to
participation in the successor to the Hubble Space Telescope.
ESA's Space Science Advisory Committee met in Paris last week
to review proposals for two classes of missions: Cornerstone missions,
large missions so named because they form the basis of ESA's science
programs; and "flexi-missions", lower-cost missions analogous to
NASA's Discovery and Explorer programs.
The committee recommended that ESA approve two Cornerstone
missions currently under consideration: BepiColombo, a Mercury orbiter
and lander, and GAIA, a telescope to accurately measure the position
of the billion brightest objects in the sky.
Those missions would be the fifth and sixth Cornerstone
missions, after the SOHO solar observatory, XMM-Newton x-ray
observatory, Rosetta comet mission, and Far Infrared and Submillimeter
Telescope (FIRST). The first two Cornerstone missions have been
launched, with Rosetta scheduled for launch in 2003 and FIRST in 2007.
BepiColombo, scheduled for launch in 2009, would be a three-
in-one mission, featuring a main orbiter, a separate magnetospheric
orbiter, and two small penetrators similar to NASA's failed Deep Space
2 Mars spacecraft. The mission will perform a comprehensive study of
the planet, including imaging of the entire planet as well as a search
for ice that may exist in shadowed craters at the planet's poles.
GAIA, the Global Astrometric Interferometer for Astrophysics,
will follow up on ESA's successful Hipparcos mission by measuring the
precise positions of one billion stars in our galaxy and beyond,
creating a three-dimensional map of the galaxy. Astronomers plan to
use that map to understand the origin and history of the galaxy as
well as theories of stellar formation and evolution. GAIA, planned
for launch no later than 2012, will also be able to detect a wide
range of other objects, ranging from supernovae to extrasolar planets.
The ESA committee also recommended the agency approve three
smaller flexi-missions, one more than originally planned, that would
fly between 2008 and 2013. Two of the three missions are
collaborations with the United States: participation in NASA's Next
Generation Space Telescope (NGST), the successor to the Hubble Space
Telescope; and the Laser Interferometer Space Antenna (LISA), a joint
mission with NASA to detect gravitational waves using lasers between
among a trio of spacecraft arranged in a triangle 5 million kilometers
(3 million miles) on a side.
The third flexi-mission is Solar Orbiter, a mission that would
provide the first up-close images of the Sun. Flying as close as 31
million kilometers (19 million miles) to the Sun, Solar Orbiter will
be able to study the solar photosphere and corona at high-resolution
using a variety of instruments, including a visible-light camera,
particle detectors, and magnetometer. As a cost-saving measure, the
spacecraft design will be based in part on components to be used on
BepiColombo.
The committee also recommended that another proposed flexi-
mission, Eddington, be selected as a backup mission that would be
developed only if NGST or LISA -- missions whose schedules are outside
of ESA's control -- ran into delays or other problems. Eddington
would fly a telescope that would be used to study the interiors of
distant stars as well as look for extrasolar planets.
The Space Science Advisory Committee passed over several other
mission proposals in making its selections, including Darwin, a
Cornerstone mission that would have been devoted to searches for
extrasolar planets as small as the Earth. Several flexi-mission
proposals advanced for consideration earlier this year were also
passed over, including Master, a Mars and asteroid flyby mission;
HYPER, a mission to study quantum electrodynamics theories; and
Storms, a three-spacecraft mission to study the Earth's magnetosphere.
The committee's recommendations will be passed on to ESA for
its consideration, although it wasn't announced when the space agency
would consider the recommended missions.
The ambitious slate of proposed missions is not without its
problems, though. The committee expressed its concern about a
potential lack of money available to do all the missions in the
scheduled time, and recommended to ESA that it look into ways to speed
up one or more missions as well as seek additional funding for these
missions.
Superoxides May Keep Martian Surface Sterile
Ultraviolet radiation bombarding the surface of the planet
Mars may create oxygen ions called "superoxides" that would prevent
the formation of organic molecules and life, scientists reported
Friday.
The results, published in the September 15 issue of the
journal Science by a team of JPL and Caltech scientists, may also
explain the unusual chemical reactions observed by the Viking landers
nearly a quarter-century ago that some thought were caused by living
organisms in the Martian soil.
The researchers found that bombarding minerals like those
found on the Martian surface with ultraviolet radiation creates
negatively-charged ions of oxygen known as "superoxides" (O2-). Such
oxides are powerful enough to react with and decompose water and
organic molecules.
"We simulated the Martian surface environment in our
laboratory and found that the combination of ultraviolet radiation,
mineral grain surfaces, atmospheric oxygen and extremely dry
conditions produce superoxide ions," explained Albert Yen of JPL, lead
author of the Science paper. "This is all that is necessary to make
the reactive component of soil."
The results may explain a number of mysteries created by a
suite of instruments on the two Viking landers designed to look for
evidence of life in the Martian soil. Despite the lack of organic
materials in the soil, some experiments -- such as one where water was
added to the soil, generating oxygen -- produced results that were
consistent with living materials in the soil.
Scientists had believed that some kind of oxide or peroxide in
the soil, rather than living organisms, created the oxygen seen in the
Viking data. However, scientists had been unable to find the
chemicals that could explain the Viking results either in the lab or
in studies of the Martian surface, leading a few to claim that the
Viking results did in fact show that living organisms existed in the
soil.
The new lab work, however, may put those claims to rest.
Superoxides react with water to create molecular oxygen at levels
consistent with the Viking data. Moreover, the superoxides, as well
as perhydroxyl (HO2-) and hydroxyl (OH-) radicals generated as a
byproduct of the superoxide-water reaction, can decompose organic
molecules, explaining the lack of such molecules in the Martian soil.
Such oxides also are relatively stable and form rapidly --
less than two weeks to form the concentrations seen in the Viking
data. In addition, the oxides can move across the surface, working
their way into soil under rocks that would be protected from
ultraviolet radiation, as also found by Viking.
"The presence of these oxygen radicals is the most
straightforward explanation for the unusual reactivity of the Martian
soil and for the apparent absence of organic molecules," the
scientists concluded in their paper.
The researchers are now turning their attention to how deep
the superoxides may exist in the Martian soil. Viking results show
similar reactions from soil samples collected 10 cm (4 in.) beneath
the surface, but there is no data yet to determine how much deeper the
superoxides may reside.
"Determining how deep that oxidizing layer is on Mars is the
most important next step in searching for life there," said Caltech
planetary sciences and geology professor Bruce Murray, a coauthor of
the paper.
"Our research does not address whether life ever formed on
Mars, but it does give us more information about where to look for
life or evidence of past life," Yen added. "Evidence of life might
exist beneath the surface or in the interiors of rocks that are
protected from the superoxide ions. What we don't know is how far
below the surface we would need to look."
ORBCOMM Files for Bankruptcy Protection
Satellite communications company ORBCOMM filed for Chapter 11
bankruptcy protection Friday, becoming the third such firm in 13
months to run into severe financial difficulties.
ORBCOMM announced Friday it and seven of its subsidiaries had
voluntarily filed for protection in federal court in Delaware under
Chapter 11 of the U.S. bankruptcy code. The filing allows the company
to continue to operate and protects it from its creditors while it
works on a plan to restructure the company.
"Filing for Chapter 11 is a necessary step in our plan to
restructure ORBCOMM, allowing us time to secure the financial
resources needed to continue to effectively serve our global network
of customers," Scott Webster, chairman and CEO of ORBCOMM, said in a
statement.
Company officials stressed that the company's constellation of
low-Earth orbit satellites will continue to operate normally during
the company reorganization. The 35 satellites, in orbits about 825 km
(510 mi.) above the Earth, provide low-bandwidth data communications
used to track and maintain contact with a variety of fixed and mobile
assets ranging from oil wells and pipelines to trucks and vessels.
Friday's announcement came after several months' of signs that
the company was not in good financial health. In June the company
announced it would seek additional investors to pump cash into the
company; ten days later ORBCOMM announced it was laying off 112
employees and contractors, 20 percent of its overall workforce.
In August the company announced a revised sales strategy that
relied on working with resellers rather than through direct sales, a
move that led to the loss of another 100 jobs at the company. On
August 15 the company announced it was not making a scheduled interest
on bonds owed by the company, triggering a 30-day grace period that
expired Friday.
ORBCOMM is owned by Canadian telecommunications firm
Teleglobe, which holds 68 percent of the company, and Orbital Sciences
Corporation, which owns the remaining 32 percent. Both companies are
working with ORBCOMM to help restructure the company.
Calling the Chapter 11 filing "a necessary step in the overall
reorganization of ORBCOMM's financial structure and business plan,"
Orbital said in a statement Friday that it would assist in ORBCOMM's
restructuring while continuing to provide technical support for
ORBCOMM's satellite constellation.
In addition, Teleglobe is providing a $17 million loan to the
company, $8 million of which has already been given to ORBCOMM. The
additional funding should be enough to keep the company operating for
the next several months while the restructuring continues.
The bankruptcy filing is the third in 13 months for the
satellite communications industry, a field that once appeared to be
extremely promising. In August of last year both Iridium and ICO
filed for Chapter 11 protection, the former after completing its
constellation of more than 70 satellites and the latter before
launching a single one.
ICO was eventually bailed out by Teledesic co-founder Craig
McCaw, who has rolled the company, now simply called New ICO, into a
holding company along with Teledesic. However, efforts to salvage
Iridium failed earlier this year, and Motorola, the company operating
the Iridium satellites, now says it plans to move ahead and
decommission the system, a process that includes deorbiting the
satellites.
Globalstar, another satellite communications company, has to
date avoided bankruptcy protection. However, in June the company drew
on a $250 million line of credit secured in large part by Lockheed
Martin. The money from that line of credit will give the company more
than enough funding to last through the rest of the year.
SpaceViews Event Horizon
September 19-21 AIAA Space 2000 conference, Long Beach, California
http://www.coola.com/cgi-bin/addinfo.cgi?pid=10003&rid=968079233&type=D
September 20 Landing of the shuttle Atlantis ending mission STS-106
at the Kennedy Space Center, Florida at 3:56 am EDT
(0756 UT)
http://www.coola.com/cgi-bin/addinfo.cgi?pid=10003&rid=969270773&type=D
September 20 Titan 2 launch of the NOAA-L weather satellite from
Vandenberg Air Force Base, California, at 6:22 am EDT
(1022 UT)
http://www.coola.com/cgi-bin/addinfo.cgi?pid=10003&rid=968079164&type=D
September 23 Western Canada Space Conference, Calgary, Alberta
http://www.coola.com/cgi-bin/addinfo.cgi?pid=10003&rid=969270981&type=D
September 25 Zenit 2 launch of a classified Russian military
satellite, from Baikonur, Kazakhstan
http://www.coola.com/cgi-bin/addinfo.cgi?pid=10003&rid=969270585&type=D
September 27 Dnepr launch of five microsatellites from Baikonur,
Kazakhstan, at approximately 6 am EDT (1000 UT).
http://www.coola.com/cgi-bin/addinfo.cgi?pid=10003&rid=969270478&type=D
October 19-22 Space Frontier Conference 9, Manhattan Beach,
California
http://www.coola.com/cgi-bin/addinfo.cgi?pid=10003&rid=968079287&type=D
October 20-22 Mars Week 2000, MIT, Cambridge, Massachusetts
http://www.coola.com/cgi-bin/addinfo.cgi?pid=10003&rid=969270315&type=D
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
Other News
GPS Modernization Contract: The U.S. Air Force awarded a $53-million
contract to Lockheed Martin September 11 to begin modernization of
Global Positioning System (GPS) satellites several years earlier that
once planned. The contract will permit Lockheed Martin to update the
systems on up to 12 of the 20 Block IIR GPS satellites the company is
building under an existing contract with the Air Force over the next
year, adding additional civilian and military signals and new
countermeasures to prevent jamming. The contract will allow the Air
Force to speed up its plans to modernize the constellation of 24 GPS
satellites: it originally planned to wait until after all the Block
IIR satellites were launched before moving forward with modernization
plans using a new series of spacecraft, the Block IIF.
Centaur Crater: A bright region on an icy body in the outer solar
system seen in a Hubble Space Telescope image may be a fresh impact
crater, astronomers said Thursday. A team of astronomers from the
University of Arizona and Lowell Observatory said that infrared
spectra taken of the two hemispheres of the small body 8405 Asbolus
show one side of the icy body is brighter and has a more complicated
spectrum that the other. "We believe we're seeing a more spherically
shaped, dark object with a very bright crater on it," said Donald
McCarthy of the University of Arizona. Asbolus is one of several
dozen Centaur objects orbiting between Saturn and Uranus. These icy
bodies are believed to be objects from the more distant Kuiper Belt
that have evolved inward through gravitational interactions with
planets or through impacts, such as the one that produced the crater
on Asbolus.
Chandra Finds Middleweight Black Hole: Astronomers announced Tuesday
that they have discovered a black hole that may be the "missing link"
between small and large black holes. Using observations by the
Chandra X-Ray Observatory, astronomers said they have discovered a
black hole near, but not exactly at, the center of the galaxy M82
whose mass -- about 500 times that of the Sun -- is greater than a
stellar black hole but smaller than a supermassive black hole.
Astronomers are unsure what could form a black hole of this size.
They hypothesize that it is either the remnant of a "hyperstar", an
extraordinarily large star that collapsed to form the black hole; or
is the product of mergers of smaller stellar black holes.
Goldin Won't Quit Early: NASA administrator Dan Goldin has no plans
to step down as head of the space agency before the Clinton
administration ends next January, SPACE.com reported last week.
Goldin, who has headed NASA since April 1992 -- the longest continuous
tenure of any NASA administrator -- told the online publication he
would remain at NASA that he "think of walking out before January 20,"
the day the new president is inaugurated. He declined to comment,
though, whether he would see to keep his job under a Gore or Bush
administration.
Satellite and Launch Contracts: Intelsat announced Friday that it had
awarded contracts to Arianespace for the launch of three of its newest
communications satellites, Intelsats 905, 906, and 907. The
satellites will be launched on Ariane 4 or 5 boosters from late 2001
through 2002... Sea Launch won a contract last week from Space
Systems/Loral to launch the Telstar 8 satellite in 2002... Hughes
announced contracts to build four communications satellites last week.
The company will build the AsiaSat 4 spacecraft for AsiaSat and three
new spacecraft for New ICO, the company that emerged earlier this year
from the bankruptcy of satellite communications firm ICO. Hughes will
also modify the eleven remaining original ICO satellites that it built
so they can provide upgraded voice and data services for the company.
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*** Articles ***
Recalling Drake's Voyages
by Jeff Foust
When many of the world's leading figures in the Search for
Extraterrestial Intelligence (SETI) gathered in Boston in May, they
did so for two reasons. One was to mark the fortieth anniversary of
the first SETI search, Project Ozma. The second was to honor the man
who led that initial SETI search, Frank Drake, on the occasion of his
70th birthday.
Most people associate Drake with that initial SETI search as
well as the famous equation drafted shortly thereafter that now
carries his name which assesses the prospects for extraterrestrial
intelligence. Few though, realize that his contributions to SETI and
astronomy in general started well before Project Ozma and continue to
his day. Those who spoke at the "Drake's Voyages" symposium at
Harvard University, though, were eager to discuss Drake's influence
and express their admiration for the man.
Drake's Start in SETI
Frank Drake's interest in the search for extraterrestial
intelligence can be traced back to his childhood, according to
professional astronomer and historian Woody Sullivan. That interest
was stoked as he was an undergrad at Cornell, when famed astronomer
Otto Struve gave a lecture there about low mass stars with slow
rotation rates. Such stars had "missing" angular momentum that had to
reside someplace else: planets, according to Struve.
After a short stint in the Navy, Drake went to graduate school
at Harvard, which, at the time (the 1950s), had the only radio
astronomy program in the country. Drake did his thesis work studying
hydrogen in the galactic center in an era when most of the radio
astronomy taking place dealt with the Sun.
It was doing observations of the Pleiades during his time at
Harvard, though, that raised his attention about the possibilities of
SETI. During those radio observations he detected a strong, narrow
signal: a "hair-raising experience", Sullivan explained, that
convinced Drake that he wanted to do SETI.
Drake would get his chance to do SETI once he graduated from
Harvard and went to the Green Bank, West Virginia facility of the new
National Radio Astronomy Observatory. Initially there were no radio
telescopes at Green Bank at all, but by 1959 a 26-meter (86-foot) dish
was in place. Drake proposed to use that telescope to look at nearby
stars in an effort to detect any signals coming from extraterrestrials
there.
While Drake's colleagues were less interested in SETI than
Drake, the proposal did attract the attention of NRAO's new director,
Otto Struve, the astronomer who raised Drake's awareness about the
potential for extraterrestrial worlds as a Cornell undergrad. While
Struve was ambivalent about radio astronomy in general, he was
interested and supportive of Project Ozma, and pushed the project
ahead, particularly after a paper by Phillip Morrison and Giuseppe
Cocconi published in Nature independently suggested that radio waves
would be an ideal way to communicate over extraterrestrial distances.
So with the blessing, and even urging, of Struve, Drake
started Project Ozma in April of 1960, using Green Bank's 26-meter
telescope to look at Epsilon Eridani and Tau Ceti, two nearby Sun-like
stars. Almost immediately Drake detected a signal. "At the time we
were very excited," recalled Drake. "We couldn't believe our luck."
However, the signal turned out to be from a secret military
project, the first of many false alarms detected by SETI projects in
the last 40 years. Project Ozma continued searching for 200 hours
over the course of two months, but failed to detect any signals of an
extraterrestrial origin. It did, though, prove that SETI was
feasible, and set the stage for more powerful searches to come.
Beyond Ozma: The Drake Equation and Arecibo
While Project Ozma failed to detect any signals from
extraterrestrial civilizations, it was a success in the sense that it
attracted the scientific community's attention to the prospects for
SETI. Drake helped organize the first SETI meeting, held at Green
Bank in November 1961, that brought together experts from a wide range
of disciplines to talk about how likely such civilizations were and
how to communicate with them.
Out of this conference came what is now known as the Drake
Equation (also known as the Green Bank Equation), the number of
extraterrestrial civilizations in the galaxy based on a number of
probabilities, such as the fraction of stars with planets, the
fraction of planets that develop life, and the fraction of planets
with life that develop technological civilizations. Since most of the
factors in the Drake Equation are unknown, the equation is something
of Rorschach test, with various people using it determine that either
such civilizations are commonplace or nonexistent.
Phillip Morrison said that the Drake Equation was perhaps the
second most influential equation of the 20th century, after Einstein's
E=mc^2. "Don't think of it as a probability," he advised, "think of it
as an agenda that leads you up a great ladder of thought."
Drake's career, though, was more than just SETI. In the 1960s
he returned to his alma mater, Cornell, because of the opportunity the
university provided to work with the Arecibo radio telescope in Puerto
Rico. Arecibo had been set up by DARPA, part of the U.S. military, in
part to track satellites, but the huge dish was also useful for radio
astronomy.
There were problems with Arecibo, though. The telescope
wasn't useful at high radio frequencies because of the coarseness of
the wire mesh surface of the dish as well as the quality of the feed
system. Moreover, its military usefulness waning, DARPA was ready to
pull the plug on the facility. Drake proposed to the National Science
Foundation a project to replace the wire mesh with a smoother surface
that worked better at higher frequencies, and add larger, better
feeds.
As a result, Arecibo became one of the premier radio astronomy
facilities on Earth, a distinction that it holds to this day. "Frank
Drake made Arecibo what it is today," said Nathan Cohen of Boston
University. "He did a tremendous engineering job."
Mike Davis, who recently left Arecibo to join the SETI
Institute, noted that Drake's work, as well as another upgrade to the
telescope performed in the 1990s, have kept Arecibo on the forefront
of science for decades. "It's unique that a scientific instrument has
lasted on the cutting edge for so long," he said.
Drake used Arecibo for SETI work, as one would imagine, but
also for other research, including early investigations into pulsars.
In 1968 he published a paper in Science about a pulsar in Vulpecula,
only the sixth pulsar yet discovered.
Still At Work
At the age of 70, one would think that Frank Drake would be
ready to begin a well-deserved retirement. Not so. Drake is still
hard at work, both discussing SETI to general and scientific audiences
and doing SETI research as well. At a technical symposium during the
Boston meeting Drake outlined what he called the "SETI efficiency", a
measure of how efficient an array of radio telescopes is at collecting
the radio signals that fall on the area it covers. While it would
appear ideal to space individual dishes closely together, the dishes
then begin to shadow one another as they track objects, reducing their
effectiveness. The solution, he said, may be to space dishes more in
the north-south direction than east-west, to maximize the
effectiveness of a radio telescope array.
His current work adds to a body of accomplishments that makes
him the leading pioneer of this still-young field. "SETI scientists
have largely elaborated on Frank Drake's work," said Seth Shostak of
the SETI Institute. Given the depth and breadth of Drake's legacy,
that's likely to be the case for many years to come.
========
This has been the September 18, 2000, issue of SpaceViews.
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