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(meteorobs) Excerpts from "CCNet 26/2001 - 15 February 2001"
The glut of "NEAR News" continues, but it is all good, so far! Now we can
imagine the fascinating new data - and surprises, and questions - that we
will certainly encounter when ESA's "Rosetta" mission makes its rendezvous
with Comet 46 P/Wirtanen in 2011!
For those unfamiliar with Rosetta, here are two fine "official" sites:
http://sci.esa.int/rosetta/
http://esapub.esrin.esadot it/sp/sp1211/interna1.htm
Clear skies,
Lew Gramer
------- Forwarded Message
From: Benny Peiser <B.J.Peiser@livjm.acdot uk>
To: cambridge-conference <cambridge-conference@livjm.acdot uk>
Subject: CCNet, 15 February 2001
Date: Thu, 15 Feb 2001 10:12:48 -0000
CCNet 26/2001 - 15 February 2001
--------------------------------
(1) NEAR SHOEMAKER READY TO GATHER DATA ON SURFACE OF EROS
NEAR Mission, 14 February 2001
(2) NEAR SHOEMAKER EXCEEDS SCIENCE & ENGINEERING EXPECTATIONS
Ron Baalke <baalke@jpl.nasadot gov>
(3) NEAR SHOEMAKER PRESS CONFERENCE SLIDES
NEAR JHUAPL, 14 February 2001
(4) ASTEROID MISSION EXTENDED: NEAR TO COLLECT MORE DATA
Space.com, 14 February 2001
(5) RUSSIAN SCIENTISTS APPRECIATIVE OF US PROBE LANDING ON EROS
Andrew Yee <ayee@nova.astro.utorontodot ca>
[...]
(8) NASA TO HOST 32nd LUNAR AND PLANETARY SCIENCE CONFERENCE
AT JOHNSON SPACE CENTER
Ron Baalke <baalke@jpl.nasadot gov>
(9) 32nd LUNAR & PLANETARY SCIENCE CONFERENCE
Michael Paine <mpaine@tpgi.com.au>
(10) NATIONAL ASTRONOMY MEETING 2001 AT THE UNIVERSITY OF CAMBRIDGE
Jacqueline Mitton <aco01@dial.pipex.com>
[...]
=============
(1) NEAR SHOEMAKER READY TO GATHER DATA ON SURFACE OF EROS
>From NEAR Mission, 14 February 2001
http://near.jhuapldot edu/news/flash/01feb14_2.html
The NEAR Shoemaker spacecraft has been commanded to begin collecting data
from the surface of 433 Eros.
NASA announced on Feb. 14 it was extending the NEAR mission for up to 10
days to gather data from the spacecraft's gamma-ray spectrometer, a
scientific instrument that could provide unprecedented information about the
surface and subsurface composition of Eros. Mission controllers at the Johns
Hopkins University Applied Physics Laboratory (APL) in Laurel, Md., have
configured the instrument to begin collecting and recording this
information.
NEAR Mission Operations Manager Robert Nelson said the team is also sending
commands to prevent the rest of the spacecraft from sending data to its
onboard recorder, since the only reliable telemetry link is through NEAR
Shoemaker's low-gain antenna. "Now that we have landed, collection and
recovery of critical gamma-ray data is our primary objective," he said.
NEAR Shoemaker's historic Feb. 12 touchdown on Eros turned out to be a
mission planner's dream - providing NEAR team members with more scientific
and engineering information than they ever expected from their carefully
designed series of descent maneuvers. The spacecraft gently landed at
3:01:52 p.m. EST, ending a journey of more than 2 billion miles (3.2 billion
kilometers) and a full year in orbit around the large space rock.
Mission operators say the touchdown speed of less than 4 miles per hour
(between 1.5 and 1.8 meters per second) may have been one of the slowest
planetary landings in history, and they now have a better picture of what
happened in the moments after the landing. What they originally thought was
a bounce may have been little more than short hop or "jiggle" on the
surface; the thrusters were still firing when the craft hit the surface, but
cut off on impact; and NEAR Shoemaker came down about 650 feet (200 meters)
from the projected landing site.
NEAR Shoemaker snapped 69 detailed pictures during the final three miles of
its descent, the highest resolution images ever obtained of an asteroid. The
camera delivered clear pictures from as close as 394 feet (120 meters),
showing features as small as 1 centimeter across. They also included several
things that piqued the curiosity of NEAR scientists, such as fractured
boulders; a football-field sized crater filled with dust; and a mysterious
area where the surface appears to have collapsed.
=========
(2) NEAR SHOEMAKER EXCEEDS SCIENCE & ENGINEERING EXPECTATIONS
>From Ron Baalke <baalke@jpl.nasadot gov>
http://near.jhuapldot edu/news/flash/01feb14_1.html
February 14, 2001
The NEAR Shoemaker spacecraft's historic soft landing on asteroid 433 Eros
Feb. 12 turned out to be a mission planner's dream - providing NEAR team
members with more scientific and engineering information than they ever
expected from the carefully designed series of descent maneuvers.
"We put the first priority on getting high-resolution images of the surface
and the second on putting the spacecraft down safely - and we got both,"
says NEAR Mission Director Dr. Robert Farquhar of the Johns Hopkins
University Applied Physics Laboratory in Laurel, Md., which manages the Near
Earth Asteroid Rendezvous (NEAR) mission for NASA. "This could not have
worked out better."
Two days after a set of five de-orbit and braking maneuvers brought it to
the surface of Eros, NEAR Shoemaker is still communicating with the NEAR
team at the Applied Physics Lab. The spacecraft gently touched down at
3:01:52 p.m. EST on Monday, ending a journey of more than 2 billion miles
(3.2 billion kilometers) and a full year in orbit around the large space
rock.
Yesterday the NEAR mission operations team disabled a redundant engine
firing that would have been activated had it been necessary to adjust the
spacecraft's orientation in order to receive telemetry from it. But because
NEAR Shoemaker landed with such a favorable orientation, and telemetry has
already been received, it was no longer necessary to move the spacecraft
from its resting place.
Mission operators say the touchdown speed of less than 4 miles per hour
(between 1.5 and 1.8 meters per second) may have been one of the slowest
planetary landings in history. They also have a better picture of what
happened in the moments after the landing: What they originally thought was
the spacecraft bouncing may have been little more than short hop or "jiggle"
on the surface; the thrusters were still firing when the craft hit the
surface, but cut off on impact; and NEAR Shoemaker came down only about 650
feet (200 meters) from the projected landing site.
"It essentially confirmed that all the mathematical models we proposed for a
controlled descent would work," says Dr. Bobby Williams, NEAR navigation
team leader at NASA's Jet Propulsion Laboratory. "You never know if they'll
work until you test them, and this was like our laboratory. The spacecraft
did what we expected it to do, and everyone's real happy about that."
NEAR Shoemaker snapped 69 detailed pictures during the final three miles
(five kilometers) of its descent, the highest resolution images ever
obtained of an asteroid. The camera delivered clear pictures from as close
as 394 feet (120 meters) showing features as small as one centimeter across.
The images also included several things that piqued the curiosity of NEAR
scientists, such as fractured boulders, a football-field sized crater filled
with dust, and a mysterious area where the surface appears to have
collapsed.
"These spectacular images have started to answer the many questions we had
about Eros," says Dr. Joseph Veverka, NEAR imaging team leader from Cornell
University in Ithaca, N.Y., "but they also revealed new mysteries that we
will explore for years to come."
NEAR Shoemaker launched on Feb. 17, 1996 - the first in NASA's Discovery
Program of low-cost, scientifically focused planetary missions - and became
the first spacecraft to orbit an asteroid on Feb. 14, 2000. The car-sized
spacecraft gathered 10 times more data during its orbit than originally
planned, and completed all the mission's science goals before Monday's
controlled descent.
"NEAR has raised the bar," says Dr. Stamatios M. Krimigis, head of the
Applied Physics Laboratory's Space Department. "The Laboratory is very proud
to manage such a successful mission and work with such a strong team of
partners from industry, government and other universities. This team had no
weak links - not only did we deliver a spacecraft in 26 months, we were
ready to launch a month early, and that efficiency continued through five
years of operations. This is what the Discovery Program is designed to do."
============
(3) NEAR SHOEMAKER PRESS CONFERENCE SLIDES
>From NEAR JHUAPL, 14 February 2001
http://near.jhuapldot edu/media/010214_pc/
===========
(4) ASTEROID MISSION EXTENDED: NEAR TO COLLECT MORE DATA
>From Space.com, 14 February 2001
http://www.space.com/missionlaunches/missions/near_writethru_010214.html
By Leonard David
Senior Space Writer
LAUREL, MARYLAND -- NASA gave a Valentine's Day gift to space scientists,
extending the mission of a spacecraft that touched down on an asteroid this
week and maintaining a radio link with the probe.
An extension of 10 days should allow scientists to glean science data
directly from the surface of Asteroid 433 Eros. Healthy telemetry from the
probe has been received ever since the safe, odds-against landing on Monday,
and the spacecraft is being checked out as to its overall health.
"This has been successful beyond our highest expectations," said Jay
Bergstralh, acting director for NASA Solar System Exploration at the
agency's headquarters in Washington, D.C. "NASA intends to take advantage of
this success by extending the mission up to 10 days."
NASA gave a green-light to Near Earth Asteroid Rendezvous (NEAR) Shoemaker
project officials to continue the mission, announcing the decision at a
press conference here at The Johns Hopkins University Applied Physics
Laboratory (APL).
APL built the spacecraft and manages the mission for NASA.
During the extended mission, APL will turn on the probe's X-ray/Gamma Ray
Spectrometer to learn more about the surface and subsurface composition of
the asteroid Eros.
The $223 million NEAR Shoemaker mission was slated to officially end on
February 14. Project funds are nearly depleted. No additional radio link
time between Earth and the craft was on tap -- that is, until the chancy
landing proved successful.
The cost of the extension is unclear, Bergstralh said. Tracking NEAR will
require the use of NASA's largest 230-foot (70-meter) radio antennas in its
Deep Space Network.
"I think this is doable on an every-other-day or every-third-day basis," he
said. "The project has some reserve. They haven't presented us with an
estimate yet."
NEAR Shoemaker continued to send signals to the NEAR team two days after the
touchdown.
A daring dive
"People are saying this was a controlled crash. No, it wasn't. This was a
controlled landing," Robert Farquhar, NEAR mission director at told
SPACE.com.
"This was a soft landing...maybe the softest of all time," Farquhar said,
contrasting NEAR Shoemaker's daring dive onto Eros with landers on the Moon,
Venus and Mars. "We landed at an impact speed between 1.5 and 1.8 meters (5
and 6 feet) per second, which is less than 4 miles (6.4 kilometers) per
hour," he said.
NEAR Shoemaker carried no landing gear and was not built for such a
maneuver.
Eros is about the size of New York's Manhattan Island -- looking like a
giant shoe -- slowly turning head over heel through space. On duty since
February 14 of last year, NEAR Shoemaker had been orbiting the huge object,
diving across its dusty terrain at various altitudes.
Before coming to a dead stop on Eros on Monday, the craft apparently made a
short hop or "jiggle" on the asteroid's surface at touchdown. Spacecraft
thrusters were still firing when the craft made contact with the surface,
but cut off on impact.
Plumes from the spacecraft's thrusters likely caused some buffeting of the
probe as it closed in on the surface.
Rest in-piece
NEAR Shoemaker is believed to have come down just 650 feet (200 meters) from
the projected landing site, a saddle-shaped featured named Himeros, at the
boundary of two major geologic provinces of Eros.
That touchdown took place after a journey of 2 billion miles (3.2 billion
kilometers) after launch on February 17, 1996.
During the 10-day extension, the probe's X-ray/Gamma Ray Spectrometer (XGRS)
will measure and map the abundance of elements present on the surface of
Eros.
"These measurements have the potential of improving the precision of our
knowledge about these abundances by a factor of 10," Bergstralh said.
Navigation feat
The probe is now resting on the asteroid in such a position that the camera
and spectrometer are pointed at the surface. But more images would not be of
any worth, Veverka told SPACE.com, as they would be out of focus. The camera
is designed to take pictures from far away, not right on the surface, he
said.
A plan to re-launch the probe from the asteroid was scrapped due to lack of
fuel.
"We have no fuel on the spacecraft, plus or minus 8 kilograms (18 pounds),"
said Robert Farquhar, NEAR mission director at the Applied Physics
Laboratory.
A more important science goal was the prospect of gathering data with the
spectrometer. Still in question is exactly what Eros is composed of, and
whether or not the asteroid matches a class of meteorite recovered here on
Earth.
Bobby Williams, leader of the NEAR Shoemaker navigation team at NASA's Jet
Propulsion Laboratory in Pasadena, California, said controlling the
spacecraft onto Eros "was a feat unparalleled in space history."
"We did something untried in the history of deep-space navigation," Williams
said, with the craft gently bumping to a full stop without flipping over.
"The good Lord smiled on us when we were landing."
Bag full of mysteries
NEAR Shoemaker snapped 69 detailed pictures during the final 3 miles (5
kilometers) of its descent, said Joseph Veverka, imaging team leader at
Cornell University in Ithaca, New York. Pictures returned show features as
small as 0.4 inch (1 centimeter) across.
Captured within those images, a number of questions pop up, Veverka said.
"NEAR Shoemaker has given us a bag full of mysteries that will keep us
scratching our heads for a long time to come," he said.
In particular, Veverka said that some process is at work on the surface that
is eroding boulders. Also, the craft imaged an area where the surface
appears to be collapsed. "What is going on is a tremendous puzzle,
especially since we're dealing with a body that has no atmosphere and
doesn't have any water," he said.
Thomas Coughlin, NEAR project manager at APL, said the mission shows that
faster, better, cheaper spacecraft can be built and flown, with better being
first. "We've shown it can work and does work and we're proof of that," he
said.
Farquhar said that the solar-powered NEAR Shoemaker is likely to remain
alive on Eros for several more months. "We think the ides of March might be
kind of bad for the spacecraft," as the Sun sets in April in relationship to
where the craft now sits, he told SPACE.com.
Copyright 2001, Space.com
===========
(5) RUSSIAN SCIENTISTS APPRECIATIVE OF US PROBE LANDING ON EROS
>From Andrew Yee <ayee@nova.astro.utorontodot ca>
[http://library.northernlight.com/FB20010214420000051.html?cb=0&dx=1006&sc=0
#doc]
Wednesday, February 14, 2001, 8:21 AM EST
MOSCOW (Itar-Tass) -- History's first soft landing of a spacecraft onto the
surface of an asteroid has become an outstanding achievement of U.S.
specialists who directed the flight of the NEAR (Near Earth Asteroid
Rendezvous) interplanetary probe, Professor Vassily Moroz, one of Russia's
major authorities on the exploration of the planets of the solar system and
head of the planetary physics department of the Space Research Institute of
the Russian Academy of Sciences, has told Itar-Tass.
Moroz evaluation is that "the American specialists succeeded in putting the
NEAR spacecraft into an orbit round such a small space body as the asteroid
Eros with a filigree accuracy and ensure a softlanding of the
inter-planetary probe on its surface". This operation, the Russian scientist
believes, has proved in practice the possibility of successful landings on
asteroids.
As for scientific data transmitted by the probe while in orbit around the
Eros and when alighting on it, "the obtained photos will be able to tell a
good deal about the structure and history of this space body", Moroz said.
The scientist pointed out that, possibly, "these data will make it possible
also to determine the structure of the surface layer of the asteroid". At
the same time the Russian expert recalled that it will take years to process
the vast amount of new data gleaned.
Copyright ) 2001 ITAR-TASS News Agency. All rights reserved.
==========
(8) NASA TO HOST 32nd LUNAR AND PLANETARY SCIENCE CONFERENCE AT JOHNSON
SPACE CENTER
>From Ron Baalke <baalke@jpl.nasadot gov>
February 13, 2001
Catherine E. Watson
Johnson Space Center, Houston, TX
(Phone: 281/483-5111)
Release: J01-14
NASA TO HOST 32nd LUNAR AND PLANETARY SCIENCE CONFERENCE AT JOHNSON SPACE
CENTER
Ancient life on Mars, oceans on Europa, a rendezvous with an asteroid -
these are just a few of the many fascinating topics that will be covered at
the 32nd Lunar and Planetary Science Conference, March 12-16, 2001, at the
NASA Johnson Space Center in Houston.
More than 450 scientists will present their research at JSC's Gilruth Center
beginning at 8:30 a.m. Monday, March 12. Oral presentations will continue
through Friday morning, March 16. Some scientists will also present their
results on posters from 7 to 9:30 p.m. Tuesday and Thursday, in the Bayou
Building at the University of Houston - Clear Lake. The media are invited to
attend both the oral and poster sessions.
One session on Monday morning will be devoted to the Tagish Lake meteorite,
which fell to Earth in northern British Columbia on Jan. 18, 2000. Early
analyses suggest that the Tagish Lake meteorite may contain the most
primitive solar system materials yet found. Researchers have also determined
that the meteroid weighed 200,000 kilograms (441,000 lbs) before it entered
the atmosphere, and was four to six meters (approximately 13 to 20 feet) in
diameter. Several hundred meteorite samples have been recovered from the
site, which is strewn along an area 16 kilometers (10 miles) long and five
kilometers (three miles) wide. The analyses of these unique samples will be
discussed in detail at the conference.
The conference, which is chaired by Carl B. Agee of JSC and David C. Black
of the Lunar and Planetary Institute, will also include presentations on
water, glaciers and volcanoes on Mars; earthquakes on Venus; and the effects
of past asteroid impacts on the Earth.
News media can register for the conference, at no charge, via the Web at:
https://www.lpi.usradot edu/htbin/meetings/lpsc2001.elec.regfrm.pl
Under "registration status" select "Working Press $0.00". News media with
additional questions, or those who wish to schedule interviews with
participants, should contact Pam Thompson at the Lunar and Planetary
Institute. Thompson can be reached by phone at 281/486-2175 or by e-mail at
thompson@lpi.usradot edu.
Additional information about conference events, including the texts of
abstracts, can be found at the Lunar and Planetary Science Conference
website:
http://www.lpi.usradot edu/meetings/lpsc2001/
===========
(9) 32nd LUNAR & PLANETARY SCIENCE CONFERENCE
>From Michael Paine <mpaine@tpgi.com.au>
Dear Benny,
Abstracts for the 32nd Lunar and Planetary Science Conference (March 12-16,
2001, Houston) are available at
http://www.lpi.usradot edu/meetings/lpsc2001/lpsc2001.download.html
regards
Michael Paine
===========
(10) NATIONAL ASTRONOMY MEETING 2001 AT THE UNIVERSITY OF CAMBRIDGE
>From Jacqueline Mitton <aco01@dial.pipex.com>
ROYAL ASTRONOMICAL SOCIETY PRESS NOTICE
Date: 14 February 2001 Ref. PN 01/06 (NAM1)
Issued by: RAS Press Officers
Dr Jacqueline Mitton
Phone: +44 ((0)1223) 564914
Fax: +44 ((0)1223) 572892
E-mail: jmitton@dial.pipex.com
Peter Bond
Phone: +44 (0)1483 268672
Fax: +44 (0)1483 274047
E-mail: 100604.1111@compuserve.com
NATIONAL ASTRONOMY MEETING 2001
TUESDAY 3 APRIL TO FRIDAY 6 APRIL 2001 AT THE UNIVERSITY OF CAMBRIDGE
A wide variety of up-to-the-minute astronomical topics will be aired at the
UK National Astronomy Meeting (NAM) for 2001, which this year is hosted by
the University of Cambridge. A highlight of the week will be a one-day
symposium on Thursday 5th April, entitled 'The Scientific Case for Human
Spaceflight'. It marks the 40th anniversary of the first human space flight
by Yuri Gagarin on 12 April 1961. NASA astronaut Jeff Hoffman is one of the
speakers.
The National Astronomy Meeting (normally held annually) is one of the most
important gathering of astronomers in the UK. It is sponsored by the Royal
Astronomical Society (RAS) and the Particle Physics and Astronomy Research
Council (PPARC). It is expected to attract about 300 professional
astronomers. The UK Solar Physics Meeting will take place in parallel with
the NAM.
Media representatives are cordially invited and press room facilities will
be available from 8.30 a.m. on Tuesday 3rd April through to the end of the
meeting at 12.30 p.m. on Friday 6th April. Scientific sessions are in the
Law Faculty Building. The press room will be the Lyttleton Room, in nearby
Selwyn College. If possible, please tell Jacqueline Mitton or Peter Bond if
you plan to attend in person, though advance registration is not essential.
Media registration is free.
The preliminary programme and more information about the NAM can be found at
http://www.astdot cam.acdot uk/~nam2001/
Further programme details will appear on this site as they become available.
The programme for the symposium on Thursday 5th April, 'The Scientific Case
for Human Spaceflight', can be found at
http://www.star.ucl.acdot uk/~iac/nam_space_meeting.html
More on the UK Solar Physics Meeting can be found at
http://www.shef.acdot uk/~uksp01
A further press notice about the NAM will be issued in mid-March.
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