Документ взят из кэша поисковой машины. Адрес
оригинального документа
: http://www.astrolib.ru/rsn/1998/11/06/
Дата изменения: Unknown
Дата индексирования: Sat Apr 9 23:32:24 2016
Кодировка: Windows-1251
Поисковые слова: impact
Электронная библиотека астронома-любителя. Книги по астрономии, телескопостроению, оптике.
Дата: 06 ноября 1998 (1998-11-06)
От: Alexander Bondugin
Тема: WDC-A R&S Launch Announcement 12974: PANSAT and Spartan 201
Привет всем!
Вот, свалилось из Internet...
> COSPAR/ISES
WORLD WARNING AGENCY FOR SATELLITES
WORLD DATA CENTER-A FOR R & S, NASA/GSFC
CODE 633, GREENBELT, MARYLAND, 20771. USA
SPACEWARN 12974
COSPAR/WWAS USSPACECOM NUMBER
SPACECRAFT INTERNATIONAL ID (CATALOG NUMBER) LAUNCH DATE,UT
PANSAT 1998-064B 25520 30 OCTOBER 1998
SPARTAN 201 1998-064C 25520 01 NOVEMBER 1998
[BOTH WERE RELEASED FROM STS 95 ON THOSE DATES.]
Dr. JIM THIEMAN
FOR
DR. JOSEPH H. KING, DIRECTOR, WDC-A-R&S.
[PH: (301) 286 7355.
E-MAIL: KING@NSSDCA.GSFC.NASA.GOV
04 NOVEMBER 1998 17:00 UT]
Further details will be in a forthcoming SPACEWARN Bulletin
Dr. Edwin V. Bell, II
_/ _/ _/_/_/ _/_/_/ _/_/_/ _/_/ Mail Code 633
_/_/ _/ _/ _/ _/ _/ _/ _/ NASA Goddard Space
_/ _/ _/ _/_/ _/_/ _/ _/ _/ Flight Center
_/ _/_/ _/ _/ _/ _/ _/ _/ Greenbelt, MD 20771
_/ _/ _/_/_/ _/_/_/ _/_/_/ _/_/ +1-301-286-1187
ed.bell@gsfc.nasa.gov
SPACEWARN home page: http://nssdc.gsfc.nasa.gov/spacewarn/
Hа сегодня все, пока!
=SANA=
Дата: 06 ноября 1998 (1998-11-06)
От: Alexander Bondugin
Тема: WDC-A R&S Launch Announcement 12975: PANAMSAT 8
Привет всем!
Вот, свалилось из Internet...
COSPAR/ISES
WORLD WARNING AGENCY FOR SATELLITES
WORLD DATA CENTER-A FOR R & S, NASA/GSFC
CODE 633, GREENBELT, MARYLAND, 20771. USA
SPACEWARN 12975
COSPAR/WWAS USSPACECOM NUMBER
SPACECRAFT INTERNATIONAL ID (CATALOG NUMBER) LAUNCH DATE,UT
PANAMSAT 8 1998-065A 25522 04 NOVEMBER 1998
Dr. JIM THIEMAN
FOR
DR. JOSEPH H. KING, DIRECTOR, WDC-A-R&S.
[PH: (301) 286 7355.
E-MAIL: KING@NSSDCA.GSFC.NASA.GOV
04 NOVEMBER 1998 21:00 UT]
Further details will be in a forthcoming SPACEWARN Bulletin
Dr. Edwin V. Bell, II
_/ _/ _/_/_/ _/_/_/ _/_/_/ _/_/ Mail Code 633
_/_/ _/ _/ _/ _/ _/ _/ _/ NASA Goddard Space
_/ _/ _/ _/_/ _/_/ _/ _/ _/ Flight Center
_/ _/_/ _/ _/ _/ _/ _/ _/ Greenbelt, MD 20771
_/ _/ _/_/_/ _/_/_/ _/_/_/ _/_/ +1-301-286-1187
ed.bell@gsfc.nasa.gov
SPACEWARN home page: http://nssdc.gsfc.nasa.gov/spacewarn/
Hа сегодня все, пока!
=SANA=
Дата: 06 ноября 1998 (1998-11-06)
От: Alexander Bondugin
Тема: John Glenn Will Conduct Tests With Aerogel On STS-95
Привет всем!
Вот, свалилось из Internet...
Marshall Space Flight Center Space Science News
http://science.nasa.gov/newhome/headlines/msad26oct98_1.htm
Right Stuff for the Super Stuff
John Glenn will conduct tests with a space age super-substance called
aerogel on STS-95
October 26, 1998: The coming return of John Glenn to space highlights the
differences between how the world looked to Americans in 1962 and how it
looks to us in 1998.
In 1962, as the first American to orbit the globe, Glenn reflected on the
delicate environmental balance that protects life on the pale blue planet
from the harsh and forbidding black matte of stars.
"Each time around, I noticed a strange phenomenon. The stars shone steady as
they neared the horizon. Then they dimmed for a bit. But the stars
brightened again before actually setting. They appeared to be passing
through a layer of haze about six to eight degrees above the earth and two
degrees thick."
The haze that Glenn described was the thin line of atmosphere: oxygen to
breathe, ozone to shield ultraviolet radiation, and carbon dioxide and
methane to trap reflected heat. The gaseous stuff of life. But from orbit,
even the Earth's atmosphere acts only as a semi-transparent window to the
starlit sky.
For Glenn's first orbital flight the mission goal was to return safely. Now
30 years later, he will use space not just as 'the high ground' but as a
working laboratory. Glenn and the other astronauts will be making the first
run at space-manufacture for a product called aerogel. In the words of early
Mercury astronauts 30 year ago, the mission will 'push the envelope' on how
aerogel can be improved. If successful, the experiment returns not just more
aerogel, but a fundamentally different kind of material, what might be
called the first "astrogel."
For windows and skylights, the "holy grail" - according to Chemical and
Engineering News - is a transparent aerogel. Current aerogels, as produced
on the ground, however, are not completely transparent, but instead have a
slight blue haze to them. However, space-manufactured aerogel has an
improved transparency that could make the substance usable in place of
window glass.
Aerogel is a remarkable substance. It's the lightest known solid, so much
akin to air that it's sometimes called "frozen smoke." Its insulating
properties are nothing short of remarkable, protecting virtually anything
from heat or cold. It was used by NASA to keep the Sojourner rover warm on
the surface of Mars where night time temperatures plunge to -100 degrees. A
single one-inch window pane of aerogel is equivalent to the insulation
provided by 32 windows panes of glass (R-20 to R-32 insulation factors).
Truly, aerogel would make a perfect window except for one thing: it's not
perfectly transparent. Aerogel made on Earth is permeated with tiny,
irregular pores that make aerogel hard to see through. There is evidence
that the irregularities are diminished when the substance in manufactured in
weightless conditions. Hence the experiment on STS-95. Astronauts will
actually manufacture some aerogel in orbit and see what happens. If aerogel
could be made transparent it could revolutionize household windows. By some
estimates, aerogel costs 3 times the price of glass, but glass manufacturing
costs are only about 10% of the purchase price for windows, so aerogel
window manufacturing might still carry a large profit margin.
Aerogel at a Glance
* Aerogel is only 3 times denser than air.
* Its index of refraction is 1 - 1.05.
* It was used to insulate Sojourner during the Mars Pathfinder mission.
* The first silica aerogels were manufactured in space in April 1996 on a
Conquest rocket.
* A 1 inch pane of Aerogel has the same insulating power as 32 panes of
ordinary glass.
Aerogel may also have a role to play in keeping the atmospheric line clear,
the thin air gap that Glenn described more than 35 years ago. By reducing
home heating costs aerogel could reduce global energy needs and minimize the
pollutants that inevitably come with energy production. Science Magazine
(1998) listed next-generation window technology as a critical point in the
US obligations to meet its international global warming commitments
prescribed by the late 1997 Kyoto Conference resolutions. The Kyoto
Conference set international standards for a 5-10% cut in carbon budgets.
This is considered impossible by some economists without triggering an
economic recession. Under the agreement, carbon percentage allotments are
proposed as tradable items and can be bought by industrialized countries
from less industrialized societies, in effect a stock market trading on
smog.
New technology could offer a way out. As an example, the December 1997 issue
of Today's Homeowner magazine listed NASA aerogel research ("Super Stuff")
in its cover story entitled "Best New Products for 1998." The article
concludes: "The potential market for a clear aerogel is enormous,
considering that window heat loss accounts for up to 30 percent of energy
lost from a home. A well-designed aerogel window could lower heating and
cooling costs by a comparable figure".
Reduced industrial waste is another long-term target of aerogel research.
Not only is aerogel of scientific interest to reduce the energy load, but
also to capture waste and polluting gases before they reach the atmosphere.
The industrial group, The Attia Applied Science, Incorporated (TAASI),
concluded in 1996: "The market for the aerogel absorbents is potentially
vast. In principle, wherever alcohol and fossil fuels are used, aerogel
absorbents
In 1998, the scientific quest to reduce the haze continues, both with deeper
environmental study and in some small part, a remarkable semi-transparent
window insulator called aerogel. Glenn's flight will be the first attempt by
space scientists to improve the transparency of aerogel and thus clear the
view. During the STS-95 mission astronauts will test whether aerogel made in
the weightlessness of space is more transparent than aerogel made here on
Earth. As progress continues, the use of clear insulation betters the
chances that over coming generations even the atmospheric haze will not
cloud our views of the stars.
Hа сегодня все, пока!
=SANA=
Дата: 06 ноября 1998 (1998-11-06)
От: Alexander Bondugin
Тема: Parkes telescope puts 1000 pulsar runs on the board (Forwarded)
Привет всем!
Вот, свалилось из Internet...
Commonwealth Scientific and
Industrial Research Organisation
Australia
Ms Rosie Schmedding (02) 6276-6520
Mobile (0418) 622-653
Fax (02) 6276-6821
Media Release: Ref 98/259 5 November 1998
PARKES TELESCOPE PUTS 1000 PULSAR RUNS ON THE BOARD
A team using CSIRO's Parkes radio telescope has just found the
thousandth pulsar known to science.
The telescope holds the international record for having discovered
the largest number of these small spinning stars since the first
was found in 1967. The new survey is clocking them up more than
ten times faster than any previous search, anywhere -- about one
for each hour the telescope is used -- and has already found more
than 200.
"This is thanks to the power of a new instrument on the telescope,
the multibeam system, which has slashed the time it takes to scan
the sky," said co-leader of the pulsar team, CSIRO's Dr Dick
Manchester.
Even surveys like this can find only a fraction of the 300,000
pulsars thought to live in our Galaxy. "Many have signals that are
too weak to pick up, or their beams are not pointing towards us,"
explained Dr Manchester.
The survey is an international collaboration between astronomers
from the University of Manchester, UK; the CSIRO Australia
Telescope National Facility; the Massachusetts Institute of
Technology, USA; and the Osservatorio Astronomico di Bologna,
Italy.
A pulsar is the collapsed core of a massive star, only 20
kilometres across, born when the original star explodes at the end
of its life.
Like an egg, a pulsar has a hard external crust covering a fluid
interior. This fluid 'neutron matter' is so dense that a piece the
size of a sugar cube has a mass of 100 million tonnes. Deep in the
pulsar's innards the density is so great that matter may exist
only as exotic subatomic particles.
A pulsar is ringed by a strong magnetic field. Electrons flung
around by the field put out a beam of radio waves. As a pulsar
spins, its beam sweeps repeatedly over the Earth and is seen as a
pulsating radio signal.
Just as biologists hunt for new species to build up a picture of
the Earth's biodiversity, astronomers hunt for new pulsars to
understand 'astrodiversity'.
"There are many different types of pulsar, and we have only a few
examples of some types," said Dr Manchester. "One of the main aims
of the survey is to find more examples of these rare types and
perhaps other types not even known or anticipated at present."
"In this survey's first hundred pulsars we found one orbiting
another neutron star -- this is only the sixth such object known."
"Most of all we'd like to find a pulsar orbiting a black hole, to
test ideas about black-hole physics. Theories predict that one
pulsar in a thousand should be in such a system," he said.
"We are particularly interested in young pulsars," said team
member Professor Vicky Kaspi of Massachusetts Institute of
Technology. "Their signals tend to glitch -- show sudden changes --
which is a sign of a 'starquake' taking place, and we can use this
to study their interiors."
"As well, some young pulsars could be counterparts of high-energy
X-ray and gamma-ray sources. We've detected many such sources but
can't identify them with any particular objects."
The more pulsars we find, the better we can understand how they
are born and evolve. "We think most of the pulsars in the Galaxy
are weak. Not many of these have been found, and so our current
estimates of how many pulsars exist and how often they are born
are rather uncertain," said Dr Manchester.
Studying a large population of pulsars also means we can better
understand what makes them 'tick'. "Like people, pulsars are all
individuals -- they have different signal characteristics," said
Dr Manchester. "We want to get beyond those idiosyncrasies to
understand how pulsars actually emit their signals."
And beyond this is the very question of what pulsars are. "The
centre of a pulsar is denser than an atomic nucleus," said Dr
Manchester. The equations that describe pulsar matter put a limit
on how fast a pulsar can spin without it breaking apart. The
fastest pulsar we know of spins around 600 times a second. If we
found one spinning faster -- say, at 1200 times a second -- that
would better pin down what pulsars are made of."
Signals from distant pulsars also reveal the conditions in the
depths of the Galaxy, said Dr Fernando Camilo of the University of
Manchester. "The space between the stars is threaded through with
magnetic fields and invisible giant clouds of electrons," he
explained. "These blur pulsar signals that travel through them.
From the nature of the blur we can reconstruct the conditions in
space. Already our survey has doubled the known number of really
distant pulsars -- those more than 20 000 light-years from the Sun
-- which are going to allow us to probe out to those distances."
A network of particularly 'fast-ticking' pulsars could even help
us to 'see' gravity waves, says Professor Matthew Bailes of
Swinburne University of Technology, who is doing another pulsar
search with the Parkes telescope.
The pulsars would be like ocean buoys that rise and fall as a wave
passes by. "A passing gravity wave would slightly alter the time
the pulsar's signal takes to reach us," said Professor Bailes.
The team members of the Parkes multibeam pulsar survey are:
Professor Andrew Lyne, Dr Fernando Camilo, Ms Nuria McKay and Mr
Dan Sheppard, Jodrell Bank Observatory, University of Manchester;
Professor Vicky Kaspi and Mr Froney Crawford, Massachusetts
Institute of Technology; Dr Nichi D'Amico, Osservatorio
Astronomico di Bologna; and Dr Dick Manchester and Dr Jon Bell,
CSIRO Australia Telescope National Facility.
The Parkes radio telescope is operated by the CSIRO Australia
Telescope National Facility.
For more information, contact:
Dr Dick Manchester
CSIRO Australia Telescope National Facility
Tel: (02) 9372-4313 (bh), (02) 9449-4534 (ah), Fax (02) 9372-4310
E-mail: rmanches@atnf.csiro.au
Professor Vicky Kaspi
Department of Physics and Center for Space Research, MIT
Tel: +1 617-253-5169, Fax: +1 617-253-0861
E-mail: vicky@space.mit.edu
Dr Fernando Camilo
University of Manchester, UK
Tel: +44-1477-571-321, Fax: +44-1477-571-618
E-mail: fc@jb.man.ac.uk
Andrew Yee
ayee@nova.astro.utoronto.ca
Hа сегодня все, пока!
=SANA=
Дата: 06 ноября 1998 (1998-11-06)
От: Alexander Bondugin
Тема: Make Your Own Balloon-Powered Asteroid Nanorover
Привет всем!
Вот, свалилось из Internet...
Make a Balloon-powered Nanorover!
Roving a mini-"planet" calls for a "mini-rover." The Japanese are
sending a spacecraft to Asteroid 4660 Nereus in 2002. With the
spacecraft will be a sample return vehicle and a little rover just
a couple of inches high. The "nanorover" ("nano" meaning very
tiny) is designed and built by the U.S. National Aeronautics and
Space Administration's Jet Propulsion Laboratory. The rover will
explore the surface of the asteroid and take pictures.
You can build a nanorover too. Try this one, made from three
styrofoam meat trays. This project is a little bit hard, so you
might want to ask a grown-up or big brother or sister to do it
with you.
Instructions for building your own nanorover is available here:
http://spaceplace.jpl.nasa.gov/muses1.htm
Hа сегодня все, пока!
=SANA=
Дата: 06 ноября 1998 (1998-11-06)
От: Alexander Bondugin
Тема: First Rotation Period of a Kuiper Belt Object Measured (Forwarded)
Привет всем!
Вот, свалилось из Internet...
ESO Education and Public Relations Dept.
Text with all links is available on the ESO Website at URLs:
http://www.eso.org/outreach/press-rel/pr-1998/phot-41-98.html
ESO Press Photo 41/98
For immediate release: 5 November 1998
First Rotation Period of a Kuiper Belt Object Measured
News from ESO Workshop on Minor Bodies in the Outer Solar System
An ESO Workshop on Minor Bodies in the Outer Solar System (ESO MBOSS-98) was
held at the ESO Headquarters in Garching, Germany, during November 2-5,
1998. Among these objects, the newly discovered Kuiper Belt Objects (KBO's)
outside the orbit of planet Neptune (also known as Trans-Neptunian Objects)
are of particular interest, but the meeting was also concerned with distant
comets and some of the small moons of the outer planets.
During these four days, about 50 specialists from all parts of the world,
observers as well as theoreticians, had a very fruitful discussion about
this rapidly expanding research field. In particular, they identified some
of the crucial questions for which answers are required in order to advance
our overall picture of the formation, evolution and interaction of these
distant bodies. Specific plans were made for collaborative studies of the
outer Solar System during the coming years.
The workshop served to review and discuss current knowledge of all minor
bodies beyond the asteroid belt, as well as their origins and
inter-relationships. Special emphasis was placed on the optimal use of
next-generation observational facilities, such as the ESO Very Large
Telescope (VLT) at the Paranal Observatory (Chile) and the Keck telescope
at Mauna Kea (Hawaii, USA). The participants enthusiastically identified
several front-line observational investigations that will take full
advantage of these powerful astronomical facilities.
Kuiper Belt Objects
The Kuiper Belt is a zone outside the orbits of Neptune and Pluto in which
icy solar system objects were expected to be present; the first was found in
1992. Since then, more than 70 KBO's have been found in orbits between
approximately 30 AU and 50 AU from the Sun (4.5 to 7.5 x 10^9 km). One of
them (designated 1996 TL66) even reaches a distance of 135 AU (20 x 10^9 km,
i.e. 4.5 times the heliocentric distance of Neptune) when it is farthest
away. It is estimated that there may be at least 100,000 KBO's larger than
100 km.
These objects probably represent the remnants of a much larger population of
such objects, formed in the early phase of the solar system, some 4.5
billion years ago. Gravitational effects from the outer planets Neptune and
Uranus and collisions soon reduced their numbers. The outermost planet Pluto
is most probably the largest member of this class of objects.
Because of their large distance, and despite their significant size, 100 -
500 km diameter, they are all very faint and can only be observed with large
telescopes. Except for their orbits, little is known about most of them,
although recent observations have shown that they have different colours,
ranging from rather blueish to red.
According to current ideas, the short period comets observed in the inner
solar system come from the Kuiper Belt and their kilometre-size "dirty
snowball" nuclei are simply small KBO's.
First rotational period of a KBO measured at La Silla
Among the highlights of this workshop was the presentation of a detailed
portrait of a Kuiper-Belt Object, designated as 1996 TO66. It was discovered
in October 1996 by a group of astronomers from the University of Hawaii,
during a survey aimed at discovering KBO's. It is one of the brightest
trans-neptunian objects known to date; its magnitude is 21.2, i.e. it is
about 1.5 million times fainter than the faintest stars visible by naked
eye.
A group of European astronomers [1] used the ESO 3.6-m New Technology
Telescope (NTT) at the La Silla observatory during 6 nights in August and
October 1997 to obtain very accurate observations of 1996 TO66, while is was
at a distance of about 45 AU.
ESO Press Photo 41/98
Image and brightness variation of Kuiper Belt Object "1996 TO66"
The top panel shows a composite image of the Kuiper Belt Object 1996 TO66
(round image at the center), totalling 4 hours of exposure with the EMMI
multi-mode instrument at the 3.6-m New Technology Telescope (NTT) at La
Silla. During the exposure, the object moved with respect to the background
stars; this motion was compensated for and the KBO therefore appears as a
point, while the images of background stars are trailed. The bright, nearly
horizontal line that crosses the entire field is the light trail left by a
geostationary satellite in orbit around the Earth, that crossed the field of
view during one of the exposures (this also serves to illustrate a specific
problem of modern astronomy -- that of increasing "light pollution" from
artificial satellites illuminated by the Sun). The lower panel is the
composite "light-curve" of 1996 TO66, showing its brightness ("red
magnitude") variations with time (in hours). The dots and the corresponding
"error bars" represent the actual measurements from several nights and their
uncertainties, while the solid line is a mathematic fit through these
points. It was used to determine the rotation period of 1996 TO66 as about 6
hours and 15 minutes.
During these nights, they took over 50 images of the object through
different optical filters; on each of these, they carefully measured its
brightness. The resulting "light-curve", cf. ESO PR Photo 41/98, i.e. the
change of brightness with time, shows a clear variation with a period of a
little over 6 hours. This is caused by rotation of the object. It is the
first time it has been possible to determine a rotation period of any KBO.
From the mean brightness of 1996 TO66, it was estimated that the diameter is
of the order of 600 km. This corresponds to just under one third of the size
of the outermost planet Pluto, making 1996 TO66 one of the largest known
KBO's. The light-curve also indicates that the object is somewhat elongated
(one axis is at least 10% larger than the others), and that the surface may
possibly have some darker and brighter regions.
Implications
This first measurement of the rotation period of a KBO is important: as 1996
TO66 is a comparatively large body, it is most likely that the rotation
period has not changed much since its formation, 4.5 billion years ago. This
is one more precious piece of information to our still very sparse knowledge
about the processes that took place when our solar system was formed.
Interestingly, (2060) Chiron, a minor planet in orbit between Saturn and
Uranus that is thought to have originally come from the Kuiper Belt, also
rotates with a period near 6 hours.
A comparison of 1996 TO66's brightness as measured through different optical
filters, indicates that it is of a grey-blue colour, similar to that of
Pluto's moon, Charon, and also the KBO 1996 TL66.
Very little is still known about the physical nature of the KBO's. They are
so remote and faint that their study, even with large telescopes, is near
the observational limits of what is possible. Nevertheless, new results like
these now pave the way towards a better understanding of the current
population of minor bodies in the outer reaches of our solar system.
When more observations of KBO's with large telescopes like the VLT become
available during the next years, it is expected that trends in their
measured physical properties (e.g. rotational state, surface properties)
will emerge. This will in turn permit more specific conclusions about the
structure of the proto-planetary disk and the processes by which the planets
and the KBO's were formed.
Note:
[1] The group consists of Olivier Hainaut, Catherine Delahodde and Hermann
Boehnhardt (ESO La Silla) and Elisabetta Dotto and Maria Antonietta Barucci
(Observatoire de Paris).
This is the caption to ESO PR Photo 41/98. It may be reproduced, if credit
is given to the European Southern Observatory.
Copyright ESO Education & Public Relations Department
Karl-Schwarzschild-Strasse 2, D-85748 Garching, Germany
Andrew Yee
ayee@nova.astro.utoronto.ca
Hа сегодня все, пока!
=SANA=
сайт служит астрономическому сообществу с 2005 года