Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V11_1/V11_145.TXT

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Subject: SPACE Digest V11 #145

SPACE Digest                                     Volume 11 : Issue 145

Today's Topics:
         NASA Headline News for 03/12/90 (Forwarded)
        One Final Opportunity To Become An Astronaut?
         Re: SR-71 Record Flight Information
             SR-71 at Smithsonian
         Re: SR-71 Record Flight Information
            Re: Artificial gravity
            Re: Artificial Gravity
----------------------------------------------------------------------

Date: 12 Mar 90 22:53:51 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: NASA Headline News for 03/12/90 (Forwarded)

-----------------------------------------------------------------
Monday, March 12, 1990                       Audio:  202/755-1788
-----------------------------------------------------------------

This is NASA Headline News for Monday, March 12

The orbiter Atlantis atop the the 747 shuttle carrier aircraft
touched down on Sunday at Biggs Air Force Base in El Paso, Texas.
The 747 has refueled and, after another overnight delay due to
weather, it will continue on to the Kennedy Space Center tomorrow
morning.


Meanwhile, at the Kennedy Space Center, the Space Shuttle
Discovery is at the Vehicle Assembly Building.  There, it is
scheduled to resume power-up interface tests to verify
connections between the orbiter, external tank, solid rocket
boosters and mobile launcher platform.


A letter to NASA Administrator Truly from the late Soviet
scientist Andrei Sakharov made a request to join with the Soviet
Union in a scientific space mission.  The White House agreed that
NASA would participate in Radioastron, to study qusars believed
to be at the cores of infant galaxies.  A Soviet 10-meter radio
radio telescope is scheduled for launch into Earth orbit in 1993
and then link up with U.S. ground-based telescopes to produce
images from deep space.


Aviation Weekly reports the Energy Department has enough
plutonium 238 to supply electrical power for two future NASA
spacecraft.  Department officials confirm a supply is available
despite comments by DOE Secretary Watkins that the U.S. plutonium
stockpile could be depleted in order to restart a reactor in
Hanford, Washington.  The Comet Rendezvous/Asteroid Flyby and
Cassini probes would need plutonium-powered electric generators
called RTGs.


Administrator Truly says the United States risks losing its
international partners in the manned space station project if
congress cuts back on the $2.6 billion requested for the project
in 1991.  He told a senate subcommittee last week that a
reduction in the President's request would create a delay.  Truly
said the Japanese, European and Canadian partners would look very
seriously at our commitment to the project.

                                   ####







-----------------------------------------------------------------
Here's the broadcast schedule for public affairs events on NASA
Select TV.  All times are Eastern.


Thursday, March 15...        Goddard Space Flight Center

          9:00 A.M.          Hubble Space Telescope science
                             briefing.

         12:00 P.M.          Preparation, deploy, and
                             verification servicing briefing.

          5:00 P.M.          How to cover the mission.
                             (for media).


Monday, March 19.....        Johnson Space Center

          9:30 A.M.          STS-31 flight directors
                             mission overview.

         10:30 A.M.          Secondary middeck student
                             experiments.

         11:30 A.M.          Flight crew news conference.


Wednesday, March 21..

          1-2:30 P.M.        Total Quality Management in Action
                             Colloquium.


Please note:  NASA Update will not be transmitted this week due
to the conference activities.  Update will resume next week.


All events and times are subject to change without notice.
-----------------------------------------------------------------
These reports are filed daily, Monday through Friday, at 12 noon,
Eastern time.
-----------------------------------------------------------------
A service of the Internal Communications Branch (LPC),
NASA Headquarters, Washington, D.C.

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

Date: 13 Mar 90 01:48:00 GMT
From: cs.utexas.edu!samsung!xylogics!transfer!lectroid!jjmhome!cpoint!frog![e-mail]  (John Woods)
Subject: One Final Opportunity To Become An Astronaut?


   I just observed in the 12 March 1990 Aviation Leak that the latest shuttle
mission had a head count one higher than the body count.  NASA and the
Air Force evidently have a human skull outfitted with radiation detectors,
used "to study the effects of radiation on the body for use in planning space
station missions and lengthy stays on the Moon or Mars."  They apparently
don't know who donated the skull, and the donor did not know that they would
be flying on the shuttle (economy class?).
   So, those of you who can't meet the usual astronaut requirements, take
heart (or some other part):
    "It is anticipated that a full torso will be flown in future
    shuttle missions to verify [a radiation] organ-dose equivalent
    model," according to a Johnson document on the project.

The facts in this article are real.  Only the interpretation need be taken
with a grain of salt.    ;-)
--
John Woods, Charles River Data Systems, Framingham MA, [phone]
...!decvax!frog!john, [e-mail], ...!mit-eddie!jfw, [e-mail]

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

Date: 12 Mar 90 13:34:58 GMT
From: amara![e-mail]  (S. Khai Mong)
Subject: Re: SR-71 Record Flight Information

In article <[e-mail]> [e-mail] (Mary Shafer (OFV)) writes:
>   the California coast near Oxnard.  They had a 6 kt tailwind.  They
>   crossed the Atlantic coast east of Salisbury, Md, decelerated, and
>   turned.  They landed at Dulles, in Chantilly, VA.  They did a low

How long and what distance does an SR-71 need to decelerate from Mach
3 to subsonic speeds?


--
Sao Khai Mong:   Applied Dynamics, 3800 Stone School Road, Ann Arbor, Mi48108
[phone] (uunet|sharkey)!amara!khai  [e-mail]

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

Date: Mon, 12 Mar 90 18:48:33 EST
From: John Roberts <[e-mail]>
Disclaimer: Opinions expressed are those of the sender
    and do not reflect NIST policy or agreement.
Subject: SR-71 at Smithsonian


>From: skipper![e-mail]  (Mary Shafer (OFV))
>Subject: SR-71 Record Flight Information

>OK, troops, here's the straight skinny, from the Lockheed full-page
>ad in the LA times, 7 March 90.

>THE ONLY PLACE TO CATCH IT
>IS AT THE SMITHSONIAN.

>    On March 6, 1990, SR-71 # 972 made its final flight, from Los Angeles
>to Washington, D.C,, setting four speed records along the way.  Rightfully,
>this Blackbird will ultimately be placed on permanent display by the
>Smithsonian Institution's National Air and Space Museaum.  It's a fitting
>tribute to a masterpiece of modern aviation.

>Mary Shafer  [e-mail] or ames!skipper.dfrf.nasa.gov!shafer
>         NASA Ames Dryden Flight Research Facility, Edwards, CA
>                   Of course I don't speak for NASA

Saying it's going to the Smithsonian doesn't quite pin it down. I expect it
will remain at Dulles, to become a part of the Smithsonian annex there, which
will also feature the prototype shuttle Enterprise (already there) and the
Enola Gay (currently at Silver Hill, in several pieces).

Question: Is it possible for the general public to see Enterprise/SR-71
now, or will we have to wait until the official opening of the annex?
                   John Roberts
                   [e-mail]

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

Date: 13 Mar 90 05:59:24 GMT
From: zaphod.mps.ohio-state.edu!uwm.edu!carroll1![e-mail]  (David C. Troup)
Subject: Re: SR-71 Record Flight Information

In article <[e-mail]> [e-mail] (Bruce Lowerre) writes:
>Better than that.  The replacement is the space shuttle.
    Somehow, I find that this is absurd. Replacing an aircraft that can be
    just about ANYWHERE, ANYTIME with a craft that flies about twice a
    year (individual orbiters) and cant do anything until it's into orbit.

>  The U-2 became obsolete when the Russians
>developed a cannon ball that could be blasted high enough to shoot it down.
    Well, a Surface to Air Missle, but a rock is a rock, huh?

>The SR-71 became obsolete when satellites were developed with telescopic
>cameras good enough to photograph the license plate of a car.
    Ahem! Wrong. When we (US) did the strike with the F-111's, where did
    the recon picts come from? A '71, thats where. The problem with the
    Key-Hole satellites is that you cant just "send one to look at Lybia"
    bacause of fuel restraints. The Blackbird is STILL a respectable recon
    platform, even though we have satellites. We still have HUMINT (Human
    Intelligence) too, and wasnt that replaced with the Camera? :-)

    One of the problems with the "Falklands War" was that there was no
    satellite coverage (that I know of) in that area.
    If anyone knows otherwise, please let me know. Thanks...

>As for mach 4 at 100,000 feet, the dream of hypersonic flight with scramjet
>engines is being researched.

    I think they're looking BEYOND mach 4. Not much left after the X-15
    tests... Thats *HYPERSONIC*. And MUCH higher than 100,000ft.

    Hey, it's realy too bad that we didnt continue with the  Boeing X-20
    Dyna-Soar...The Soviets have one..Or maybee we do too. :-)

    A vehicle like the X-20 would be VERY usefull today. A fleet of about
    20 or so would be desirable.

    later folks...

--
David C. Troup ! SkunkWorks ! 2600 hz           |"Im going to work at an office
       [e-mail]                   | that has no phone, and
    414-524-6809(dorm)7343(work)                | returning home with sandy
The Surf Rat - DC 12 on Neil Pryde and Seatrend | feet."

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

Date: Mon, 12 Mar 90 17:08:28 EST
From: John Roberts <[e-mail]>
Disclaimer: Opinions expressed are those of the sender
    and do not reflect NIST policy or agreement.
Subject: Re: Artificial gravity


>From: cs.utexas.edu!jarvis.csri.toronto.edu!helios.physics.utoronto.ca!physics.utoronto.ca![e-mail]  (Christopher Neufeld)
>Subject: Re: Artificial Gravity

>   But it does keep accelerating. Remember, acceleration is the time rate
>of change of the velocity vector (speed or direction or both). A point on
>the rim of a hoop of radius 'r' rotating at a constant angular velocity 'w'
>experiences an acceleration of r*w*w. This is a measure of the force needed
>to keep pushing the object in a circular path, when it would really rather
>move in a straight line.

An equivalent is acceleration = v*v/r, where v is the instantaneous value of
the velocity in the direction of travel.

..............................

>From: sdcc6!sdcc3![e-mail]  (Sir Six)
>Subject: Re: Artificial Gravity rephrased

>     There's an interesting scene in _2001_ when Commander Poole (or
>was it Bowman?  hmm.  whatever) jogs around the spinning carousel.
>I was just thinking, would he get a better workout by jogging in the
>same direction as the spinning of the carousel than be jogging in
>the opposite direction?  (My thinking is that one would effectively
>increase the angular velocity while the other would effectively
>decrease it, and therefore that one would increase the centrifugal
>force while the other would decrease it.)  eh?

He would weigh more running in the direction of spin. If he ran against the
direction of spin fast enough to cancel out the spin velocity, he would
become "weightless", and drift around until something slammed into him.

In fact, once he gets moving, there is no need for the cylinder to spin -
his own motion holds him against the surface. The Skylab astronauts did
this in imitation of the movie "2001" (there was a film loop in the Air
and Space Museum showing the stunt).

In contrast to the clever special effects of "2001", in "2010" the crew
walk around on the floor normally (justified by the spinning section of
the craft), *except* when Dr. Floyd places several objects in midair, and
they float! It's not even plausible that this is along the axis of rotation.
I suppose it must have been pushed through by some scriptwriter who claimed
"It's a great special effect, and nobody will notice the inconsistency."
..............................
   John Roberts                  "I didn't overact! I DIDN'T OVERACT!!!"
   [e-mail]               - Roy Scheider

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

Date: 13 Mar 90 02:45:19 GMT
From: cs.utexas.edu!jarvis.csri.toronto.edu!helios.physics.utoronto.ca!physics.utoronto.ca![e-mail]  (Christopher Neufeld)
Subject: Re: Artificial Gravity

In article <[e-mail]> [e-mail] (Tom Neff) writes:
>In article <[e-mail]> [e-mail] (Eric Pepke) writes:
>>Another thing is that, while the cylinder is spinning, you wouldn't be
>>able to change the direction of the ship, so you would have to stop it for
>>direction changes.
>
>This turns out not to be true.
>
>Gyroscopic effects only occur when the delta-vee is out of the plane
>of rotation!  So long as course corrections are in-plane, you can handle
>it with coordinated thrusters.
>
   This is a bit unclear. Just to make sure we're talking about the
same thing, imagine the ship is a hoop rotating in space, with a
central shaft and drive lying along the axis of rotation. If that's
not clear, take the space station from 2001, and put an engine where
the docking port is, so that it thrusts along the axis of the ring.
   There are three possible rotations of this structure (assuming it
is a rigid body). Roll, which doesn't change the direction in which
the needle is pointing, and pitch and yaw which are interchangeable in
absence of a well-defined up and down. Roll has little use if you're
trying to change course. Pitch and yaw result from pushing on the
front of the needle in one direction, and the back of the needle in
the other direction. Both of these look like a gyroscope being brought
from vertical to some angle from the vertical.
   This action tries to change the angular momentum vector through the
angle subtended by the nose of the ship. In order for this to happen,
the rotating ring has to experience a torque. This torque would stress
the bearings and wall supports, probably enough to require a more
rugged design if you wanted to change the ship's orientation quickly
while the carousel was spinning.

>So how do you change the plane of rotation?  Flywheels.
>
   This would still stress the mountings of the big carousel. To avoid
this stress, the carousel would have to experience a torque sufficient
to move it together with the needle. I can't see a way to do this by
putting flywheels on the carousel.
   The scheme I could imagine would be the following: build the ship
with the carousel stationary, and a stationary flywheel which spins
along the same axis. Spin up the carousel against the flywheel so that
the total angular momentum of the ship is zero. This way you can spin
the carousel down again without spinning the whole ship around its
axis and without firing reaction jets to discard the angular momentum.
Now, with everything standing still, turn the ship to your new
heading, and spin up the carousel and countering flywheel to restore
gravity to the carousel.
   Of course, this scheme requires two rotational couplings. A more
likely proposal in terms of reliability would probably be to make the
whole thing rigid (so that the needle also spins with the same angular
velocity as the carousel) and strong enough to take the turning
torques, and then do it brute force without spinning things down. If
you have weeks to prepare for your turns this shouldn't be too
difficult.

   Now, if you propose that the carousel lies on the back of the
needle, or is mounted longitudinally within the body of the needle,
then you need not make such elaborate preparations for a course
change.

>--
>Annex Canada now!  We need the room,    \)      Tom Neff
>    and who's going to stop us.         (\      [e-mail]


--
 Christopher Neufeld....Just a graduate student  | "I always think there's
 [e-mail]              | a band."
 [e-mail]          Ad astra! |   Prof. Harold Hill
 "Don't edit reality for the sake of simplicity" |   (The Music Man)

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

End of SPACE Digest V11 #145
*******************