Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT_ZIP/spacedig/V15_1/V15NO153.ZIP/V15NO153

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Date: Tue,  1 Sep 92 04:59:58
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #153
To: Space Digest Readers
Precedence: bulk


Space Digest                Tue,  1 Sep 92       Volume 15 : Issue 153

Today's Topics:
                                DCX??
            Fireball over The Netherlands Wasn't (4 msgs)
                        HST Update - 08/31/92
                        Shuttle seen from air
                        UARS Update - 08/31/92
                 Upload Astronomy Lab for MS Win 3.x
                            Venus orbiters
                       What happened to Viking?
          What is the speed of light measured from? (4 msgs)

    Welcome to the Space Digest!!  Please send your messages to
    "[e-mail]", and (un)subscription requests of the form
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    (THENET), or [e-mail] (Internet).
----------------------------------------------------------------------

Date: 31 Aug 92 09:59:23 GMT
From: Patrick Chester <[e-mail]>
Subject: DCX??
Newsgroups: sci.space

>    | Allen W. Sherzer | "If they can put a man on the Moon, why can't they     |
>|  [e-mail]     |  put a man on the Moon?"                               |
>+----------------------238 DAYS TO FIRST FLIGHT OF DCX----------------------+
                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^???
Pardon me for seeming clueless, but what is the dcx?


Thank you.

Patrick Chester

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

Date: Mon, 31 Aug 1992 07:42:08 GMT
From: Harm Munk <[e-mail]>
Subject: Fireball over The Netherlands Wasn't
Newsgroups: sci.space,sci.astro

On wednesday, August 19, seismic stations located in the northwestern part
of the Netherlands registered an atmospheric shock wave, which, apparantly,
was not related to any seismic activity. In the following days, the Royal
Dutch Meteorological Institute (KNMI) in the Netherlands investigated the
matter and came to the conclusion that it had probably been a meteor with a
cross section of 30 cm which had exploded over the town of Joure in Friesland
(a Dutch province).

[See previous postings on Fireball over NW Europe]

Later investigations by the KNMI and a group of astronomers showed that the
only possible explanation left is not a meteorite or space junk, but some kind
of supersonic, military airplane breaking the sound barrier some ten miles west
of the island of Texel. According to the KNMI, this is the only explanation left
allthough it is an unsatisfactory one.

Because it supposedly was a military airplane, the KNMI contacted the military
airbase Aurora in Scotland, but the spokesperson at Aurora did not know
of any observation of a supersonic, military aircraft that evening.

So, what was it? Rumours in the newspapers suggested that it was that highly
secretive airplane that Lockeed is developing for the DoD: the two stage get
to orbit plane (like DynaSoar and Saenger ?). Now, this plane has been sighted
in the US a few times.

The supposed sighting in the Netherlands was accompanied not only by sonic
booms (energetic enough to crack the front of a house somewhere in the province of
Friesland) but some people reported seeing a flash of light as well. Was this
also the case with the sightings in the US?

And why would the DoD start testing a secret plane outside US territory?

And why was someone from Lockeed Space and Missiles Systems asking questions
on the net about this event (;-)?

+----------------------------------------+------------------------------------+
| Harm Munk                              | Building WAY 11                    |
| Philips Research Laboratories          | P.O. Box 80 000                    |
| Knowledge Based Systems                | 5600 JA  Eindhoven                 |
|                                        | The Netherlands                    |
| #include <standard.disclaimer>         | tel. [phone]               |
|                                        | email: [e-mail]         |
+----------------------------------------+------------------------------------+

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

Date: Mon, 31 Aug 1992 13:36:51 GMT
From: Gerald Cecil <[e-mail]>
Subject: Fireball over The Netherlands Wasn't
Newsgroups: sci.space,sci.astro

In article 715246928@prles6b, [e-mail] (Harm Munk) writes:
>On wednesday, August 19, seismic stations located in the northwestern part
>of the Netherlands registered an atmospheric shock wave, which, apparantly,
>was not related to any seismic activity .. but some kind
>of supersonic, military airplane breaking the sound barrier some ten miles west
>of the island of Texel. According to the KNMI, this is the only explanation left
>allthough it is an unsatisfactory one. ...
>The supposed sighting in the Netherlands was accompanied not only by sonic
>booms (energetic enough to crack the front of a house somewhere in the province of
>Friesland) but some people reported seeing a flash of light as well. Was this
>also the case with the sightings in the US?
They probably saw a low-flying military aircraft with its afterburners on.  Maybe
it punched through a low-lying cloud deck on its way out.

>Rumours in the newspapers suggested that it was that highly
>secretive airplane that Lockeed is developing for the DoD: the two stage get
>to orbit plane (like DynaSoar and Saenger ?). Now, this plane has been sighted
>in the US a few times. ...
According to Aviation Week & Space Technology (aka AvLeak) in issues prior to
Aug. 24, this aircraft is an
SR 71 replacement developed by Lockheed Skunkworks.  Speeds estimated at 3500+ mph.
*Not* a 2 stage to orbit plane. It has only been seen near the ground
dimly at night, and was described as `bat-like'' similar to the B2 airfoil. People
report a low frequency, growling noise of tremendous power at takeoff.  Daytime
photos of peculiar corkscrew contrails that have been attributed to this aircraft
suggest an ``explosive'' or pulsed propulsion system, but the observers did not have
binoculars to see the plane itself (flying at high altitudes). AvLeak reports an
increasing number of daytime sightings like this, suggesting that the program is
emerging from the so-called Black (i.e. non-itemized) DoD budget into full
Congressional scrutiny, presumably because the DoD has now sunk so much money into
it and distributed its contractors into so many Congressional districts that the
program is unkillable. Yet another multi-billion dollar aerospace program to
protect US airspace from the Bosnian airforce.

>And why was someone from Lockeed Space and Missiles Systems asking questions
>on the net about this event (;-)?
S/he was probably searching for a new job.
---
Gerald Cecil [e-mail]  919-962-7169
Physics & Astronomy, U of North Carolina, Chapel Hill, NC 27599-3255 USA

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

Date: 31 Aug 92 15:59:44 +0100
From: Alan Greig <[e-mail]>
Subject: Fireball over The Netherlands Wasn't
Newsgroups: sci.space,sci.astro

In article <munk.715246928@prles6b>, [e-mail] (Harm Munk) writes:
>
> Because it supposedly was a military airplane, the KNMI contacted the military
> airbase Aurora in Scotland, but the spokesperson at Aurora did not know
> of any observation of a supersonic, military aircraft that evening.

Can't say I've ever heard of a military airbase called Aurora in Scotland.
Sounds a very unlikely name for an RAF base in any case.
--

Alan Greig                            Janet: [e-mail]-TECH
Dundee Institute of Technology          Tel: [phone]
Scotland, UK

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

Date: Mon, 31 Aug 1992 18:10:33 GMT
From: [e-mail]
Subject: Fireball over The Netherlands Wasn't
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Alan Greig)
writes:
>In article <munk.715246928@prles6b>, [e-mail] (Harm Munk) writes:
>>
>> Because it supposedly was a military airplane, the KNMI contacted the
military
>> airbase Aurora in Scotland, but the spokesperson at Aurora did not know
>> of any observation of a supersonic, military aircraft that evening.
>
>Can't say I've ever heard of a military airbase called Aurora in Scotland.
>Sounds a very unlikely name for an RAF base in any case.
>--
>
>Alan Greig                            Janet: [e-mail]-TECH
>Dundee Institute of Technology        Tel: [phone]
>Scotland, UK
>

Aurora isn't an RAF base, it's the code name for a SR71 replacement.
It would appear (according to sc.military) that the new plane operates
out of a test facility out west (a'la U2/SR71), and uses Machrihanish
base in the U.K. as it's European base. More information on this can
be found on the sc.military newsgroup - although the information is
(understandbly) sparse and subject to interperatation.

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

Date: Tue, 1 Sep 1992 06:01:01 GMT
From: Ron Baalke <[e-mail]>
Subject: HST Update - 08/31/92
Newsgroups: sci.space,sci.astro

Forwarded from the SpaceLink BBS

                       HUBBLE STATUS REPORT
                         August 31, 1992

HUBBLE SPACE TELESCOPE (HST):  HST operations have returned to
normal following the recent safehold entry and recovery. Starting
on July 30, a chain of events caused HST first to enter an
inertial hold safemode followed by a hardware sunpoint safemode.
The first was caused by an incorrect ephemeris table that was
loaded into the spacecraft computer, and the latter by a problem
with an onboard computer software macro. Science observations
that were scheduled for execution during the safemode events are
being rescheduled. HST launched April 24, 1990 aboard the Space
Shuttle Discovery.
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Anything is impossible if
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | you don't attempt it.
|_____|/  |_|/       |_____|/                     |

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

Date: 1 Sep 92 04:32:36 GMT
From: John Roberts <[e-mail]>
Subject: Shuttle seen from air
Newsgroups: sci.space

-From: [e-mail] (Henry Spencer)
-Subject: Re: Need GIF (JPG, whatever) of Shuttle Landing
-Date: 26 Aug 92 18:44:05 GMT

-In article <[e-mail]> [e-mail] (WENDY WARTNICK) writes:
->wouldn't it be cool if NASA or the Air Force or someone would send up some
->sort of high altitude/space chase plane for cool space shots...

-I've seen a photo of a shuttle launch seen from the air, from the Shuttle
-training aircraft I think.

NASA Select occasionally replays Shuttle launches as seen from the air
(helicopters?), and sometimes video shot out the side of the Shuttle
(ground dropping away).

Of course, video doesn't generally make great still pictures.

John Roberts
[e-mail]

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

Date: Tue, 1 Sep 1992 06:03:06 GMT
From: Ron Baalke <[e-mail]>
Subject: UARS Update - 08/31/92
Newsgroups: sci.space,sci.astro

Forwarded from the SpaceLink BBS

                       UARS STATUS REPORT
                        August 31, 1992

UPPER ATMOSPHERE RESEARCH SATELLITE (UARS): Attempts to restart
the Improved Stratospheric and Mesospheric Sounder (ISAMS)
chopper wheel motor have not been successful.  The motor stopped
working on July 29. The chopper wheel breaks up or "chops" the
incoming light beam for analysis. Automated attempts to restart
the chopper motor continue. ISAMS measures ozone, nitrogen
compounds and other gasses important in ozone depletion. Most of
these compounds are measured by other UARS instruments, so the
loss of ISAMS has minimal impact on the UARS science mission at
this time.  UARS launched September 12, 1991 from the Space
Shuttle Discovery.
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Anything is impossible if
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | you don't attempt it.
|_____|/  |_|/       |_____|/                     |

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

Date: 31 Aug 92 14:36:40 GMT
From: Eric Bergman-Terrell <[e-mail]>
Subject: Upload Astronomy Lab for MS Win 3.x
Newsgroups: comp.windows.ms.programmer,comp.windows.ms.misc,comp.ibm.pc.misc,comp.os.ms-windows.apps,sci.space,sci.astro,sci.edu

If you are willing to upload Astronomy Lab version 1.13 to an ftp site
or bbs, I'd like to e-mail you a uuencoded .zip file of the program.

You must be able to handle a ~500k e-mail message containing the uuencoded
program.  After uploading the program, please send me instructions on how
users can upload the program.

...

Astronomy Lab is an astronomy program for MS Windows 3.X.
Astronomy Lab produces 7 movies that simulate a host of
astronomical phenomena, 15 graphs that illustrate many
fundamental concepts of astronomy, and 14 reports that
predict the most important astronomical events.  All
movies, graphs, and reports are customized for the user's
time zone and location.  The entire User's Guide is
available as on-line help.  This is version 1.13.

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

Date: 1 Sep 92 04:37:54 GMT
From: John Roberts <[e-mail]>
Subject: Venus orbiters
Newsgroups: sci.space

-From: [e-mail] (Ron Baalke)
-Subject: Re: Venus orbiters
-Date: 26 Aug 92 07:07:16 GMT
-Organization: Jet Propulsion Laboratory

-In article <[e-mail]>, [e-mail] (Jeff Bytof) writes...
->Is the Pioneer Venus orbiter still functioning?

-Yup, but it is running out of propellent and is due to burn up in the
-atmosphere of Venus this December.

Will the trajectory of Pioneer Venus as it burns up provide useful
information for the planning of the Magellan aerobraking experiment?
(Density and drag at various altitudes, etc.)

John Roberts
[e-mail]

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

Date: 1 Sep 92 04:58:54 GMT
From: John Roberts <[e-mail]>
Subject: What happened to Viking?
Newsgroups: sci.space

-From: [e-mail] (Eugene N. Miya)
-Subject: Re: What happened to Viking?
-Date: 21 Aug 92 22:27:39 GMT
-Organization: NAS, NASA Ames Research Center, Moffett Field, CA

-In article <[e-mail]>
[e-mail] (John Burris) writes:
->I heard through the grapevine that someone sent a bogus signal to it which
->turned the antenna away from Earth, resulting in LOS.

-That was Voyager II (briefly).

The way I heard it was that the last lander still running was given a
command that effectively translated as "point antenna at ground and wait
for next command from Earth".

Since then, NASA's gotten considerably better at the use of safe modes
and watchdog timers. (For instance, Magellan might have only 1% coverage
rather than 97% without such protection.)

John Roberts
[e-mail]

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

Date: Mon, 31 Aug 1992 13:36:21 GMT
From: "Robert B. Whitehurst" <[e-mail]>
Subject: What is the speed of light measured from?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Steve) writes:
>
>OK. Someone can perhaps clear this little nagging thought in my head.
>
>I haven't done any relativity, or any complicated physics, so please
>keep it simple.
>
...[asks about invariance of speed of light]
>Where is the speed of light measured relative to?
>
>Steve
>
Steve,
    As other posts in answer discuss, the speed of light (in a
given media) is invariant.  However, its direction of travel and
source speed relative to the observer DOES affect its frequency.  I'm
sure you have heard sirens rise and fall in pitch as they approach and
leave you.  That is the Doppler effect, and light does the same.  The
light is blue- or red-shifted if the source and you are approaching or
leaving each other.  Astronauts traveling very near light speed would
see a very strange star field, with the stars in front shining blue
(or even UV, or X-ray if you are fast enough) and the ones behind
showing red.  Weird stuff indeed!

--

Brad Whitehurst    |   Aerospace Research Lab
[e-mail] |   We like it hot...and fast.

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

Date: Mon, 31 Aug 1992 17:34:11 GMT
From: "robert.f.casey" <[e-mail]>
Subject: What is the speed of light measured from?
Newsgroups: sci.space

Makes you wonder how the "particle" of light "knows" how fast or slow to
speed up by to be travelling at the -speed o' light- at or near the
local frame of reference.  Does it "feel" the local gravity, or something?

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

Date: 31 Aug 92 18:38:49 GMT
From: "Frederick A. Ringwald" <[e-mail]>
Subject: What is the speed of light measured from?
Newsgroups: sci.space

In article <[e-mail]>
[e-mail] (robert.f.casey) writes:

> Makes you wonder how the "particle" of light "knows" how fast or slow to
> speed up by to be travelling at the -speed o' light- at or near the
> local frame of reference.

A particle of light (a photon) always travels the SAME speed, in a
vacuum, relative to all observers. It doesn't have to know anything.
It's the structure of space and time that changes: it's described at
length in any special relativity text, such as Spacetime Physics by
Taylor & Wheeler.

> Does it "feel" the local gravity, or something?

YES - the gravitational deflection of starlight was one of the major
tests of general relativity, the one that made Einstein a household
name. A good introductory text on general relativity is Gravitation &
Spacetime, by Hans O'Hanian, although GR is not a field for the faint
of heart or mathematically disinclined. Pity, too, since if you happen
to already be a differential geometer, the physical theory is
stunningly simple and beautiful: a typical course will spend about half
the term developing math, two or three days discussing the theory, and
the rest of the term talking about applications (neutron stars, black
holes, post-Keplerian celestial mechanics as in the orbit of Mercury,
etc.).

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

Date: 31 Aug 92 19:22:31 GMT
From: "Frederick A. Ringwald" <[e-mail]>
Subject: What is the speed of light measured from?
Newsgroups: sci.space

In article <[e-mail]>
[e-mail] (robert.f.casey) writes:

> Makes you wonder how the "particle" of light "knows" how fast or slow to
> speed up by to be travelling at the -speed o' light- at or near the
> local frame of reference.

A particle of light (a photon) always travels the SAME speed, in a
vacuum, relative to all observers. It doesn't have to know anything.
It's the structure of space and time that changes: it's described at
length in any special relativity text, such as Spacetime Physics by
Taylor & Wheeler.

> Does it "feel" the local gravity, or something?

YES - the gravitational deflection of starlight was one of the major
tests of general relativity, the one that made Einstein a household
name. A good introductory text on general relativity is Gravitation &
Spacetime, by Hans O'Hanian, although GR is not a field for the faint
of heart or mathematically disinclined. Pity, too, since if you happen
to already be a differential geometer, the physical theory is
stunningly simple and beautiful: a typical course will spend about half
the term developing math, two or three days discussing the theory, and
the rest of the term talking about applications (neutron stars, black
holes, post-Newtonian celestial mechanics as in the orbit of Mercury,
etc.).

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

End of Space Digest Volume 15 : Issue 153
------------------------------