Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_4/V16NO447.TXT

Internet Message Format | 1993-07-13 | 32KB

Date: Sat, 10 Apr 93 05:16:13
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #447
To: Space Digest Readers
Precedence: bulk


Space Digest                Sat, 10 Apr 93       Volume 16 : Issue 447

Today's Topics:
                  Alaska Pipeline and Space Station!
                           B0940e70000e341
                      Biosphere 2, In Praise of
            Budget Astronaut (was: Idle Question) (2 msgs)
                           EJASA, Apr 1993
              HELP: orbital elements for sun/moon/earth
                     MACH 25 landing site bases?
     Mars Observer Mapping Mission to Begin Earlier Than Planned
                   Michael Jordan in Space Problem
        Mir 2's planned orbit [was Re: Degrees vs. experience]
                             NASA "Wraps"
             Question- Why is SSTO  Single Stage (3 msgs)
                             Shuttle fax
                     SN 1993J and Gravity Waves?
              Three Spacecraft Search for Gravity Waves
             Two-Line Orbital Element Set:  Space Shuttle

    Welcome to the Space Digest!!  Please send your messages to
    "[e-mail]", and (un)subscription requests of the form
    "Subscribe Space <your name>" to one of these addresses: listserv@uga
    (BITNET), rice::boyle (SPAN/NSInet), utadnx::utspan::rice::boyle
    (THENET), or [e-mail] (Internet).
----------------------------------------------------------------------

Date: 07 Apr 93 17:38:40 GMT
From: Ralph Buttigieg <[e-mail]>
Subject: Alaska Pipeline and Space Station!
Newsgroups: sci.space

Original to: [e-mail]
G'day [e-mail]

04 Apr 93 18:24, [e-mail] wrote to All:

 ao> [e-mail] (Allen W. Sherzer), via Kralizec 3:713/602

 >> to pay for it, so interest charges are less.

 ao> And this, ladies and gentlemen, is why the US has a multi-trillion $$
 ao> debt.

 ao> No Gary, the governemnt does indeed pay interest.

 >> The sticking point is that the government has to sign a firm rental
 >> agreement in advance of construction that guarantees a certain amount
 >> of rent for a specified period once construction is complete. And that
 >> contract has to have penalty clauses sufficient to keep the landlord
 >> solvent if the government reneges on the contract. This has been the
 >> sticking point. Most government contracts have a termination clause

 ao> Not any more. Last years NASA Authorization bill allows NASA to
negotiate
 ao> termination liability.

It seems to me that the main problem in developing Space is not so much the
technology but the institutions charged with the job. There is nothing wrong
with the principle of handing the Station to commercial concerns, and in
fact should be able to deliver a better, cheaper alternative. What is
stopping it happening is the reluclance of the various institutions.

This is similar to the trouble the DC-X had. The basic concept has been
around for years. However it took constant prodding over many years and a
new institution - SDIO to achieve.

Perhaps this is were Space supporters should turn their efforts to now. The
slow, arduous task of changing these institutions.

Example - Instead of NASA ESA & NASDA International Space Station we have an
organisation modelled on the successful Intelsat, lets call it Space
Stations International. They raise funds from national shareholders and
commericial sources. They pay off their investors by charging rent to the
users.

Some advantages are:

1) Far more likely to get a Station the researchers actually want. Properbly
2 or 3 small, specialized Stations rather then the "one size fits all"
Freedom model.

2) It would be a proper commercial enterprise, the research itself, not the
actual Space Station would be its main purpose. Would use tried and true
technolgy in its construction, rather then be a technological experiment in
itself.

3) Free from government restrictions IntelStation could purchase the best
technology fo the job. American hardware on Russian rockets, serviced by
Chinese launchers or whatever.

4) Far more likely to lead to profit making Space enterprises. Ventures
undertaken by IntelStation would be at realistic low cost. Not gold plated
Freedom costs.

5) Be a true International Space Station. Many more countries, even my own
would likely be willing to invest.

The main disadvantage would be the need to get the pollies (Australian slang
for politicians) to agree to steadly pay the rent. Also it would bypass much
of the national pork barrelling.

However considering that the current effort has resulted in billions being
spent to produce zilch. Perhaps taxpayers would indeed support such a
project.

ta

Ralph

--- GoldED 2.41
 * Origin: VULCAN'S WORLD - Sydney Australia [phone]  3:713/6
(3:713/635)

------------------------------

Date: Fri, 09 Apr 1993 06:25:00
From: John Witter <[e-mail]>
Subject: B0940e70000e341
Newsgroups: sci.space

IMFjU[
      w5+h[# l'U+70000e341
*B07000000273351
ll
bQk/W21J~%V~HE3o7:`4wj

John
?





l







                 i








m
m
f
#j{7~mmg2}


 * Origin: *AmeriComm*, 214/373-7314. Dallas'Info Source. (1:124/6507)

------------------------------

Date: 10 Apr 1993 01:40:35 GMT
From: "David M. Palmer" <[e-mail]>
Subject: Biosphere 2, In Praise of
Newsgroups: sci.space

Just to put things into perspective:

The head of Biosphere threw millions of dollars of his own money down
the toilet to get a theme park and less science than the critics wanted.

NASA threw millions of dollars of YOUR money down the toilet and got...
            a toilet.

Now, which one is it more reasonable to bitch about?


(By the way, the people who complain about the cultish aspects of
Biosphere probably are not familiar with Disney.)

--
        David M. Palmer        [e-mail]
                    [e-mail]

------------------------------

Date: 10 Apr 1993 05:27:02 GMT
From: George William Herbert <[e-mail]>
Subject: Budget Astronaut (was: Idle Question)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] writes:
>>A) How big is the absolute minimum atmospheric re-entry and life
>>support module for the aspiring low-cost astronaut? ...
>George Herbert estimated a minimum one-man capsule as just feasible
>for the new stretched Pegasus, which puts Scout out of the running unless
>you can beat George's weight numbers substantially.  (Probably possible,
>but maybe only by fairly radical methods.)

Ah, Henry didn't read the vehicle mission specs on my capsule all that
closely did he 8-)

My manned capsule's "minimal"ness is not quite as minimal as you can
go and still safely land a human.  I included about three days worth
of life support and enough delta-V to maneuver to and dock with
a space station in my design; it wasn't supposed to be a tourist
pod, it's a working vehicle.  (I wouldn't want to live in it for three
days, but... 8-)

I'd estimate from other work of mine that a 275-300 kilo vehicle could
be made that would _safely_ sustain life for a few hours and return
the crewman to the surface.  Perhaps a bit less if you don't have to
ride in the capsule all the way to the surface; the parachute size
goes down a bit, but mission safety is reduced.  Still a bit too
big for a Scout.  A person with a heatshield, a re-entry solid rocket,
and a space suit might fit on a scout, but it would be way unsafe
and there would be no systems redundancy.  I wouldn't recommend it.

-george william herbert
Retro Aerospace

------------------------------

Date: 10 Apr 1993 05:34:16 GMT
From: George William Herbert <[e-mail]>
Subject: Budget Astronaut (was: Idle Question)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Frank Crary) writes:
>Definitely possible: George is 6'2" and insists that any project
>he works on be large enough to, in theory, fit himself. You could
>probably cut the mass of his manned Pegasus capsule by 5% to 10%,
>just by insisting on a 5'0" astronaut...

Frank, you know better.  I'm 6'4.5", not 6'2".

[And when I worked the numbers on the capsule-for-vertically-impaired-people,
it came out about 2.5% lighter, not a "whole" lot 8-) ]

The insistence that I fit is true.

(You all will have to excuse Frank; the low pressure up in Boulder has
addled his brain a bit, it appears.  He was totally normal when
he was here at Berkeley, really... ;-)

-george

------------------------------

Date: 10 Apr 1993 04:17 UT
From: Ron Baalke <[e-mail]>
Subject: EJASA, Apr 1993
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Jonathan McDowell) writes...
>Posted on behalf of Larry Klaes.
>
>        There were some disagreements between U.S. and Soviet scientists
>    on the origins of certain surface features.  For example, the probes'
>    owners declared that the 96-kilometer (57.6-mile) wide crater at the
>    summit of 10,800-meter (35,640-foot) high Maxwell Montes, the tallest
>    mountain on the planet, was the result of a meteorite impact.  American
>    scientists, on the other hand, felt the crater was proof that Maxwell
>    was a huge volcano sitting on the northern "continent" of Ishtar Terra.
>

This believe this was named Cleopatra and it is very interesting feature.
The Magellan images revealed that it was *both* a meteor crater and a volcano.
Apparently, a large meteor impacted the surface and this then resulted in
subsequent volcanic activity.
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Being cynical never helps
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | to correct the situation
|_____|/  |_|/       |_____|/                     | and causes more aggravation
                                                  | instead.

------------------------------

Date: Fri, 9 Apr 1993 13:37:39 GMT
From: "Randy Stackhouse, N4RTL" <[e-mail]>
Subject: HELP: orbital elements for sun/moon/earth
Newsgroups: sci.space

Hi.  Would someone e-mail me the orbital elements of the Earth around the
Sun and moon around the earth?   If possible, I would prefer an element set
that described the rotation of the sun around the earth (no jokes or flames
please...)   Thanks in advance

------///-------------------------------------------------------------------
     /// Randy Stackhouse, N4RTL | Author of SatTrack the satellite tracking
    ///  GENIE: RSTACKHOUSE      | program for the Amiga.  Version 3.0
\\ ///   INTERNET: [e-mail]
 \X//    YELLNET:  HEY!RANDY     | [phone]

------------------------------

Date: 8 Apr 93 16:53:37 GMT
From: Paul Campbell <taniwha!paul>
Subject: MACH 25 landing site bases?
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] writes:
> The supersonic booms hear a few months ago over I belive San Fran, heading east
> of what I heard, some new super speed Mach 25 aircraft?? What military based
> int he direction of flight are there that could handle a Mach 25aircraft on its
> landing decent?? Odd question??

East of SF at Mach 25 - just about any base in the continental US .....
at ~15k mph you can cross the country in < 1/2 an hour .....

    Paul
--
Paul Campbell    UUCP: ..!mtxinu!taniwha!paul     AppleLink: CAMPBELL.P
"Finally after much thought he tied a dollar bill to the top of the tree, it
seemed to fit - after all it was the premier capitalist holiday, besides after
the 'fall' of communism a star didn't seem appropriate anymore ..."

------------------------------

Date: 9 Apr 1993 20:19 UT
From: Ron Baalke <[e-mail]>
Subject: Mars Observer Mapping Mission to Begin Earlier Than Planned
Newsgroups: sci.space,sci.astro,alt.sci.planetary

From the "JPL Universe"
April 9, 1993

Mars Observer mapping mission to begin earlier than planned
By Diane Ainsworth

     The Mars Observer spacecraft will begin its mapping mission
about three weeks sooner than planned to ensure that data
collection is well under way before Martian dust storms begin to
sweep over the planet in February 1994.
     Plans to begin the science experiments on Nov. 22, 1993,
rather than Dec. 12, had been written into the baseline strategy
for the mission, but could not be considered until fuel surplus
after launch and the first trajectory correction maneuver had
been determined, project officials said. The Mars Observer
planetary science group ratified the decision in mid-February to
begin science observations 21 days ahead of schedule.
     "We had ideal launch conditions," said Suzanne Dodd, Mars
Observer mission planning team chief, "and the Titan III launch
vehicle and Transfer Orbit Stage (TOS) booster performed so
efficiently that we conserved enough fuel to begin the mission
early."
     The spacecraft will use the "power in" approach to drop more
rapidly into its final, two-hour mapping orbit, Dodd said.
Spacecraft descent from the time of capture in Mars orbit until
it reaches the mapping orbit will take 75 days rather than 96
days, and will require seven braking maneuvers to bring the
spacecraft into its 2 p.m. solar orientation.
     The spacecraft's booms will not be fully deployed until the
final polar orbit has been achieved, Dodd said, but some science
experiments will be operating as the highly elliptical orbit
begins to tighten around the planet.
     The Magnetometer and Gamma Ray Spectrometer -- mounted on
separate booms -- will be able to make unique measurements of the
interactions of magnetic field lines with the solar wind that
will not be observable from the lower altitude mapping orbit,
said Dr. Arden Albee, Mars Observer project scientist.
     "For the first 10 1/2 days, the spacecraft will be crossing
in and out of the planet's magnetic field in a three-day
elliptical orbit," Albee said. "This will be a critical period
for Magnetometer and Gamma Ray Spectrometer calibrations. Noise
from the spacecraft will have to be subtracted out from the
magnetic signatures of Mars and that can only be done as the
spacecraft moves closer and then farther away from this planetary
boundary."
     Twenty-one days after orbit insertion, the spacecraft will
be in a one-day orbit around the planet. The Deep Space Network
will begin to track the spacecraft continuously and, using the
Doppler shift, measure the Martian gravity field.
     The Thermal Emission Spectrometer and Mars Observer Camera
may also be operated simultaneously during spacecraft descent,
Dodd said. Those instruments had not yet been approved for
operation when Universe went to press, but a decision was

expected within a few weeks. The camera, which will have taken
its first picture of the planet 28 days before orbit insertion,
would be turned on to begin acquiring narrow-angle images of star
fields and the limb of the Martian surface.
     Mission operations team members said a solar conjunction
that will occur on Dec. 20, 1993, and last through Jan. 3, 1994,
also prompted the decision to begin science operations early.
During the conjunction, the sun will be between Earth and the
spacecraft, blocking spacecraft communications.
     "From an operational standpoint, we wanted to make sure that
all orbit maneuvers and boom deployments were completed before we
lost communication with the spacecraft," Dodd said. "On the
science side, one complete mapping cycle takes 26 days, so we
wanted to have one nice, clear map of Mars before solar
conjunction."
     "There is a very distinct advantage to getting this first
mapping cycle right up front," Albee added. "The Martian dust
storms run roughly between February and August, so the atmosphere
should be very clear in November. It will also provide us with an
excellent opportunity to obtain data before and after a dust
storm."
     Mars Observer will reach its near-circular mapping orbit 378
kilometers (234 miles) above the planet's surface on Nov. 8 of
this year. At that time, the last two solar panels will be
deployed and the science booms will be fully extended. In its
mapping configuration, the spacecraft will map the red planet for
an entire Martian year, the equivalent of about two Earth years
or 687 Earth days.
                                ###
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Being cynical never helps
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | to correct the situation
|_____|/  |_|/       |_____|/                     | and causes more aggravation
                                                  | instead.

------------------------------

Date: Sat, 10 Apr 1993 05:32:16 GMT
From: Arthur Chandler <[e-mail]>
Subject: Michael Jordan in Space Problem
Newsgroups: sci.space

   I know this is trivial; but haven't you ever wondered something
ridiculous and then couldn't get it out of your mind?  Anyway , if this
is *infra dignitatem* for this group, please ignore.
   So:

   What is the largest body in the solar system on which, if Michael
Jordan jumped straight up, he would achieve escape velocity?

  All speculations gratefully considered. Thanks.

------------------------------

Date: Sat, 10 Apr 1993 03:32:41 GMT
From: Henry Spencer <[e-mail]>
Subject: Mir 2's planned orbit [was Re: Degrees vs. experience]
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Chris Jones) writes:
>It's not clear exactly why the orbital inclination for Mir 2 has been changed
>from the current Mir's 51.62 degrees to 65 degrees.  One guess ...
> is that the Russian's are being cautious about depending on a launch
>site outside of their country (Baikonour is in Kazakhstan)...

Aviation Leak says that this is exactly the reason:  they'll be launching
from Plesetsk.  This means setting up Proton launch facilities at Plesetsk,
but they seem to think it's worth it.
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
                    - Kipling           |  [e-mail]  utzoo!henry

------------------------------

Date: 9 Apr 1993 18:39 CDT
From: [e-mail]
Subject: NASA "Wraps"
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Allen W. Sherzer) writes...
>In article <[e-mail]> [e-mail] (David B. Mckissock) writes:
>>Allen Sherzer & Tim Kyger write:
>>  "Another problem is what are called 'wraps' (or sometimes
>>   the 'center tax'). When work for a large program like
>>   Freedom or Shuttle is performed at a NASA center, the
>>   center skims off a portion which goes into what amounts
>>   to a slush fund...
>
>
>BTW, universities do the same thing. They however, have a wrap of
>10% to 15% (again, this is over and above any overhead charge).
>
>   Allen
>


Wrong Allen. The max overhead charge is ALL of the charge. There is no
seperately budgeted overhead in any shape size form or fashion. How do
I know? I write proposals and have won contracts and I know to the dime
what the charges are. At UAH for example the overhead is 36.6%. At Utah
State it is somewhat higher. At Stanford it was really overboard. All of
the schools that I have experience with use the overhead percentage number
and that is ALL the system can charge on a contract.

This puts into question your assertation about NASA. I admit I do not
know how every dime is spent at MSFC but there is no big ticket item like
you state. If you look at where NASA money is spent MSFC is the largest
reciepient of NASA money, much more than JSC due to the fact that most
shuttle program money gets paid out from here (ET's SRB's SSME's payload
operations).

I know that MSFC gets somewhere in the billions per year. If your asertation
were correct that would mean that the skim is near a billion per year. This
is prima facia absurd. Where the heck is the money going? To lawfully
contracted programs. There are small amounts of money that the center director
has. These are called the Center Director Discretionary Fund or CDDF. This money
is given out each year to low level efforts that may lead to future major
funded efforts. ATLAS mission currently in orbit began this way. The MSFC
75KVA DC power system began this way. Our SEDSAT is partially funded by this
money.

BUT

There is no big money in this fund. No proposals that I have heard of have
been funded over $150,000 per year for no more than three years. There
are very few of these even. Most are in the $20,000-$50,000 range and go
for no more than a couple of years.

If you have some numbers Allen then show them else quit barking. I have no
doubt that some SSF money is being used for non-SSF purposes. There is a
new building at MSFC that was paid for from SSF money. This building is for
the people that will be working on SSF (as it was). You could loosely state
that this money was not spent directly on SSF, but it was in support of it.
This is the only stretch in this direction  that could even make
any plausable sense.

Dennis, University of Alabama in Huntsville

BTW

By your own numbers Allen, at a cost of 500 million per flight the
service cost of flying shuttle to SSF is 2 billion for four flights, so how
did you get your one billion number?

------------------------------

Date: 9 Apr 93 20:26:17 GMT
From: Paul Dietz <[e-mail]>
Subject: Question- Why is SSTO  Single Stage
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Henry Spencer) writes:

> People built two-stage airliners once.  Nobody bothers any more.  It's
> just not worth the extra performance.

This is true, but there are significant differences between
airliners and launchers.  Transoceanic jets have mass ratios of
around 50%.  Staging doesn't gain much payload.  SSTO launchers,
the other hand, have mass ratios from 10% to as little as 3%
(if they use dense fuels).  The effect on payload could be much
larger.  Even low-performance dumb strap ons could significantly
affect payload.

    Paul F. Dietz
    [e-mail]

------------------------------

Date: 9 Apr 1993 20:09:37 -0400
From: Pat <[e-mail]>
Subject: Question- Why is SSTO  Single Stage
Newsgroups: sci.space

 How about Solid Strap ons  to give a little extra kick.

C-130's  used to have JATO packs for short field take off.

I bet the castor is cheap enough now to give a decent  boost
at startup,  and it's small.

Granted it increases complexity and all that sort of thing,
but would it work?

pat

------------------------------

Date: Sat, 10 Apr 1993 04:10:45 GMT
From: Josh Hopkins <[e-mail]>
Subject: Question- Why is SSTO Single Stage
Newsgroups: sci.space

[e-mail] (Pat) writes:

> How about Solid Strap ons  to give a little extra kick.

>C-130's  used to have JATO packs for short field take off.

In fact, lots of planes have used them.

>I bet the castor is cheap enough now to give a decent  boost
>at startup,  and it's small.

There are several sizes of solid booster motors, some of which are sizeable
enough to be first stages of smaller vehicles.

>Granted it increases complexity and all that sort of thing,
>but would it work?

It could be made to work (with certain modifications to the boosters and/or
the main engine operations).  In fact, it has been talked about, though I don't
know just how high up or how seriously. However, the whole point of an SSTO is
that it doesn't use such things.  If you add boosters it isn't an SSTO, and
many of the features (low cost, launch from simple sites) dissapear.
--
Josh Hopkins                                          [e-mail]
          "Tout ce qu'un homme est capable d'imaginer, d'autres hommes
                     seront capable de le realiser"
             -Jules Verne

------------------------------

Date: Fri, 9 Apr 93 21:22:33 EDT
From: John Roberts <[e-mail]>
Subject: Shuttle fax

Ha! The fax machine on the Shuttle is jammed yet again, and they're using
the backup printer.

(This time they're calling it "the thermal printer that the astronauts
use to receive printed instructions", but we know what they're talking
about. :-)

John Roberts
[e-mail]

------------------------------

Date: 10 Apr 1993 04:24 UT
From: Ron Baalke <[e-mail]>
Subject: SN 1993J and Gravity Waves?
Newsgroups: sci.astro,sci.space

In article <BELS1722B1C2A2@MPA15C>, MPA15C![e-mail] writes...
>I notice that SN 1993J was detected after the current Gravity Wave
>experiment with Galileo/Mars Observer/Ulysses.
>

I noticed this too.  I think SN 1993J would be an excellent candidate for
generating gravity waves.  It is rather fortunate that the supernova occurred
during the gravity wave experiment.  Keep in mind, however, that the
analysis of the data from gravity wave experiment and correlating the
data between the three spacecraft will take months.
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Being cynical never helps
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | to correct the situation
|_____|/  |_|/       |_____|/                     | and causes more aggravation
                                                  | instead.

------------------------------

Date: 9 Apr 1993 20:27 UT
From: Ron Baalke <[e-mail]>
Subject: Three Spacecraft Search for Gravity Waves
Newsgroups: sci.space,sci.astro,sci.physics,alt.sci.planetary

From the "JPL Universe"
April 9, 1993

3 spacecraft help in search for Einstein-predicted gravity waves
By Franklin O'Donnell

     During an otherwise quiet part of their interplanetary
cruises, three JPL spacecraft are being used in a novel
experiment to find something that Albert Einstein predicted but
no one has yet detected directly -- gravity waves.
     The experiment, which began March 21 and ends Sunday, April
11, makes use of the Mars Observer, Galileo and Ulysses
spacecraft, all currently cruising en route to their respective
destinations.
     During the three-week effort, antennas of JPL's Deep Space
Network have been sending signals to each of the spacecraft,
which in turn sends a signal at the same frequency back to Earth.
     Any slight change in the frequency could be caused by a
passing gravitational wave emitted by a collapsing black hole or
other distant celestial event.
     "Albert Einstein predicted the existence of gravitational
waves in his theory of general relativity, and radio astronomy
observations of pulsars have suggested they indeed exist -- but
no one has ever detected a gravitational wave directly," said Dr.
John Armstrong of JPL's Radio Frequency and Microwave Subsystems
Section 333, who is working with the Mars Observer and Galileo
spacecraft.
     According to Einstein, waves of gravity are emitted by
astrophysical bodies undergoing extreme acceleration. The waves
themselves are ripples in the fabric of space-time moving at the
speed of light.
     Some cosmic events major enough to produce gravitational
waves that could be detected near Earth include collapses of
masses of stars in the hearts of galaxies and the spiraling
together and collision of two black holes.
     Detection of gravitational waves will give scientists new
information on the interiors of these catastrophic events.
Sensitive interferometer antennas are being built in the United
States and Europe to search for gravitational waves with
wavelengths of thousands of kilometers.
     "In addition to searching for the shorter waves that can
affect antennas here on Earth, we can use radio signals sent to
spacecraft hundreds of millions of kilometers away to search for
waves of much longer wavelength," said Dr. Frank Estabrook of the
Space Physics and Astrophysics Section 328, who is working with
the Galileo spacecraft.
     If strong enough, a passing gravitational wave will warp the
fabric of space between the spacecraft and Earth so that the
frequency of the spacecraft's radio signal changes.
     The hydrogen maser clocks that control the DSN transmitters
and receivers are so accurate that scientists are be able to
detect a change in radio frequency of as little as a few parts in
a quadrillion (1 followed by 15 zeroes).
     "This should allow us to detect gravitational waves from
objects such as massive pairs of black holes hidden in the hearts
of other galaxies," said Hugo Wahlquist of JPL (also from Section
328), who is working on the Ulysses spacecraft with JPL's Sami
Asmar (Section 339), Prof. Bruno Bertotti of the University of
Pavia, Italy, and Prof. Luciano Iess of the University of Rome La
Sapienza.
     The experiment is the first time observations have been made
simultaneously with multiple spacecraft, which greatly increases
the reliability of any detection.
     The team acknowledges, however, that snaring a gravitational
wave during the experiment will depend on a good bit of luck
--whether or not a suitable astronomical event happens to occur
during the three-week opportunity when data can be taken.
     The three spacecraft are all in the night sky currently, so
interference with their radio signals due to charged particles in
the solar wind is at a minimum.
     Mars Observer, launched in September 1992, will reach the
red planet Aug. 24 of this year.  Launched in 1989, NASA's
Galileo spacecraft will arrive at Jupiter in 1995. The joint
NASA-European Space Agency Ulysses spacecraft was launched in
1990 to fly over the sun's poles in 1994 and 1995.
                                  ###
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Being cynical never helps
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | to correct the situation
|_____|/  |_|/       |_____|/                     | and causes more aggravation
                                                  | instead.

------------------------------

Date: Fri, 9 Apr 1993 21:01:30 GMT
From: TS Kelso <[e-mail]>
Subject: Two-Line Orbital Element Set:  Space Shuttle
Newsgroups: sci.space

The most current orbital elements from the NORAD two-line element sets are
carried on the Celestial BBS, [phone], and are updated daily (when
possible).  Documentation and tracking software are also available on this
system.  As a service to the satellite user community, the most current
elements for the current shuttle mission are provided below.  The Celestial
BBS may be accessed 24 hours/day at 300, 1200, 2400, 4800, or 9600 bps using
8 data bits, 1 stop bit, no parity.

Element sets (also updated daily), shuttle elements, and some documentation
and software are also available via anonymous ftp from archive.afit.af.mil
(129.92.1.66) in the directory pub/space.

STS 56
1 22621U 93 23  A 93 98.58333332  .00059346  00000-0  17143-3 0    53
2 22621  57.0034 177.2911 0006562 270.2987 339.7131 15.92539873    50
--
Dr TS Kelso                           Assistant Professor of Space Operations
[e-mail]                    Air Force Institute of Technology

------------------------------

End of Space Digest Volume 16 : Issue 447
------------------------------