Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V09_6/V9_605.TXT

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Date: Thu, 17 Aug 89 00:27:06 -0400 (EDT)
Subject: SPACE Digest V9 #605

SPACE Digest                                      Volume 9 : Issue 605

Today's Topics:
          Re: Space telescope - why only 1200 hours?
               Re: Hipparchos satellite
         Re: Request for more info on ozone depletion
              Re: Future probe to Pluto
              Earth's perihelion
           Re: Don't Mess with NASA (afterburners)
           Re: Don't Mess with NASA (afterburners)
      Re: Cheerleading (was Re: Henry's (not Weinhards))
         re: Neptune Encounter Satellite Feed
           Re: Quick and Dirty Won the Race
                Re: Satellites
              Buying the hottest jet...
----------------------------------------------------------------------

Date: 31 Jul 89 13:32:57 GMT
From: bfmny0![e-mail]  (Tom Neff)
Subject: Re: Space telescope - why only 1200 hours?

Of course, an unmanned scope on the back side of the moon would share some
of HST's disadvantages.

    1. The Moon would block 50% of the sky at all times - worse than HST
    2. It still couldn't point at the sun (better to say "musn't" :-) )
    3. Dust and debris on the primary would be an even worse problem since
       it would be located on a giant dustball instead of in orbit
    4. Calibration would be just as necessary, esp. with an unmanned scope.

And of course

    5. All command and data flow would have to be indirect.

All in all I think it would be best to build observatories with human
labor, on the Moon's visible side near the limb.  That way Earth is just
a cookie on the horizon without significant observing impact, but you
get direct data feeds.  With humans building it, you can get clever and
work out solutions to the dust and debris problems, and anchor it firmly
so calibration can be held at a minimum.
--
"My God, Thiokol, when do you     \\    Tom Neff
want me to launch -- next April?"  \\    uunet!bfmny0!tneff

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

Date: 2 Aug 89 07:52:02 GMT
From: mcvax!hp4nl!esatst![e-mail]  (Neil Dixon)
Subject: Re: Hipparchos satellite

From article <[e-mail]>, by [e-mail] (Greg Goebel):
> to a satellite named "Hipparchos" -- which was to be launched in 1985
> to determine the positions of stars with high accuracy.  (I believe it
> was an ESA project.)

The latest launch date is now 8th-9th August, from Kourou.


--
Neil Dixon <[e-mail]> UUCP:...!mcvax!esatst!neil, BITNET: NDIXON@ESTEC
Thermal Control & Life Support Division (YC)
European Space Research and Technology Centre (ESTEC),
Noordwijk, The Netherlands.

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

Date: 2 Aug 89 12:33:08 GMT
From: mailrus!uflorida!haven!ncifcrf!nlm-mcs!adm!smoke![e-mail]  (Irving Chidsey )
Subject: Re: Request for more info on ozone depletion

In article <[e-mail]> [e-mail] (Helen Grayson) writes:
<In article <[e-mail]> [e-mail] (Irving Chidsey (INF) <chidsey>) writes:
<>...the earth is farther from the sun during the Northern winter...
<
<According to my Trivial Pursuits set (so it *must* be right :-)
<the Earth is closest to the Sun in January.
<
<(I'm sure this doesn't help at all.)
<
<Helen.
OOPS! You're right, soft memory error!  Just flipped a bit.

It doesn't affect my point, which was that there is a difference between the
poles that might explain why we had only one hole.  It certainly doesn't
affect Ilana Stern's lucid explanation.  Helps it in fact as it makes the
South pole colder.

                    Irv


--
I do not have signature authority.  I am not authorized to sign anything.
I am not authorized to commit the BRL, the DOA, the DOD, or the US Government
to anything, not even by implication.
            Irving L. Chidsey  <[e-mail]>

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

Date: 2 Aug 89 17:10:05 GMT
From: att!shuxd![e-mail]  (Michael L. Starr)
Subject: Re: Future probe to Pluto

In article <[e-mail]> [e-mail] (Raymond Lister) writes:
|
|    Pluto-Jupiter-Earth line up favourably for a gravity assist about every 12
|    years ... [the next launch window will occur] in the 1980's to early
|    1990's.  [Four bright guys at] JPL have examined this period ... After a
|    1989 launch, Pluto would be encountered by the 800kg spacecraft after 10
|    years of flight, having been boosted by a combination of chemical thrusting
|    and gravity assists by earth (re-encountered 2.2 years after launch after
|    looping out in space in a so-called delta Vega trajectory) and
|    Jupiter. ..."
|
|The current launch window has been missed, but if they launch in 2001, I'll
|see pictures of Pluto just before I retire.

Unfortunately, with NASA's instance on using the Space Shuttle to launch
everything, it'll never happen.  NASA needs to return back to the good
old reliable (and it turns out cheaper) expendable rockets!  Look how
long Galileo has been sitting around waiting for a launch (9 years now?).
A repeat of the success of Voyager could never happen today.
----
 __/\__  ********************  __/\__   |       [e-mail]
 \    /  * Michael L. Starr *  \    /   |       att!shuxd!starr
  |/\|   ********************   |/\|    |       attmail!starr

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

Date: 2 Aug 89 08:30:33 GMT
From: mailrus!jarvis.csri.toronto.edu!csri.toronto.edu![e-mail]  (Wayne Hayes)
Subject: Earth's perihelion

In article <[e-mail]> [e-mail] (Helen Grayson) writes:
>In article <[e-mail]> [e-mail] (Irving Chidsey (INF) <chidsey>) writes:
>>...the earth is farther from the sun during the Northern winter...
>
>According to my Trivial Pursuits set (so it *must* be right :-)
>the Earth is closest to the Sun in January.

Chock one up for Trivial Pursuit: Earth's Perihelion is on January 2, distance
91,397,000 miles (147 090 000 km).
--
------------------------------------------------------------------------------
"Open the pod bay doors, HAL."   "I'm sorry Dave, I'm afraid I can't do that."
Wayne Hayes    INTERNET: [e-mail]    CompuServe: 72401,3525

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

Date: 2 Aug 89 05:37:37 GMT
From: portal!cup.portal.com![e-mail]  (Mark Robert Thorson)
Subject: Re: Don't Mess with NASA (afterburners)

[e-mail] (Allen W. Sherzer) says:

> There are more than one. I know of people who own F-86's. A company in
> Addison Tx. has imported some Alpha jets which it sells (for about 2M
> each). A company in CA inports MIG-19's from China and is attempting to
> get permission to import MIG-21's. The Alpha and Mig-21 will do better
> than mach 1.

I was under the impression that a plane has to be FAA certified for use in
American airspace.  Are the MiG's certified?

I believe this was the objection raised when a private group submitted a
bid for the USAF Adversary Aircraft program.  This was to be a procurement
of planes for use in training American pilots in combat against planes
with performance similar to that of Soviet-built planes.  USAF created this
procurement specifically to justify purchase of the F-20.  Originally, F-20
was the only bidder, but then along came this group with arrangements to
obtain authentic MiG's and spare parts from China and Israel.  Their bid
was rejected because it didn't meet "the requirements of the Adversary
Aircraft program".  Their protests that these planes ARE the adversary
aircraft came to no avail, last I heard (a few years ago, in Electronics News).

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

Date: 2 Aug 89 15:50:50 GMT
From: dinl![e-mail]  (kevin w. holroyd)
Subject: Re: Don't Mess with NASA (afterburners)

In article <[e-mail]> [e-mail] (Mark Robert Thorson) writes:
|
|I was under the impression that a plane has to be FAA certified for use in
|American airspace.  Are the MiG's certified?
|
|I believe this was the objection raised when a private group submitted a
|bid for the USAF Adversary Aircraft program.  This was to be a procurement
|of planes for use in training American pilots in combat against planes
|with performance similar to that of Soviet-built planes.  USAF created this
|procurement specifically to justify purchase of the F-20.  Originally, F-20
|was the only bidder, but then along came this group with arrangements to
|obtain authentic MiG's and spare parts from China and Israel.  Their bid
|was rejected because it didn't meet "the requirements of the Adversary
|Aircraft program".  Their protests that these planes ARE the adversary
|aircraft came to no avail, last I heard (a few years ago, in Electronics News).


Only CIVILIAN airplanes have to be certificated by the FAA.  Those flown by
military or government agencies do not.  Also the pilots of non-civilian
airplanes do not require pilot's licenses.  (e.g. a state trooper flying
a state police airplane does not have to have a pilot's license, but most
of them do anyway.)

--
*******************************************************************************
Kevin W. Holroyd            *
CFI Aspen Flying Club            * Got tired of last .signature file
Denver CO.                *
*******************************************************************************

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

Date: 1 Aug 89 17:50:43 GMT
From: hpfcdc!hpfcdj![e-mail]  (Bob Myers)
Subject: Re: Cheerleading (was Re: Henry's (not Weinhards))

>>John W Campbell used to say that there has never in the history of the world
>>been a democracy that lasted 100 years, and that the US would not be the
>>first. Depending on you viewpoint, the US became a democracy either in 1906
>>or 1964. I tend to believe 1964 myself.

>This is quite bogus (though I have no doubt John Campbell actually said that).

>Someone is likely to point out that the US is still not a democracy because
>there is discrimination against <insert group here>.  Thus, according to
>the definition of democracy given above, no country has ever been a democracy.
>This makes the statement true, but only trivially.

Why would anyone think that, in a democracy, there will be no discrimination
against "<insert group here>"?  A pure democracy is actually the most LIKELY
form of government to permit discrimination, as the absolute rule of the
majority is not subject to any form of checks and balances, and so it is likely
that the rights of a given minority will be abrogated.  Technically, the
U.S. is still basically a republic, as our laws are generated (primarily)
by a body of elected represenatives - although there has been a disturbing
trend in the latter half of this century for legislative power to be delegated
away to bureaucratic organizations (EPA, FCC, FAA, DoT, etc.).  (This trend
seems to me to be a step further away from democracy, as the commissioners.
secretaries, etc., are not directly elected.)

(I am curious about the dates given above, although my somewhat rusty
memory leads me to believe that these are the years in which changes were
made to the presidential election process.  If so, I fail to see how relatively
minor changes in the process to elect the chief *executive* of the government
relate to whether or not that government is a democracy.)

Followups should probably be directed to talk.politics.misc, although I find
myself reading that group more and more seldom.  Poor S/N ratio.


Bob Myers            | "Man will occasionally stumble over the truth, but
myers%hpfcla@hplabs. |  most of the time he will pick himself up and continue."
hp.com               |                        - Winston Churchill

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

Date: Wed, 2 Aug 89 12:36:06 EDT
From: [e-mail]
Subject: re: Neptune Encounter Satellite Feed

I was excited and frustrated by the following posting:

> NASA has purchased time on the AURORA-1 satellite for broadcasting
> live pictures of the Voyager Neptune encounter. The broadcasts
> will be August 21 through 29 from 12 Noon until 6:00 pm. The
> broadcast will be for all 24 hours on August 24. AURORA-1 is at
> 139 degrees west for those with satellite dishes.

I'm racking my brains for someone nearby with the equipment and the
inclination to let me sit in their control room all night on the
24th while I use their dish for my amusement. Our cable company
isn't interested, though I'm going to try again.

I wonder if C-SPAN could be persuaded to transmit some of this
material in the middle of the night for us addicts? I'll have to
call them and see what they say.

Of course what I'd *really* like would be someone to make the
digital images available over the Internet, but I've been in this
business too and you don't ship your raw data out to the peons till
you've wrung them dry of discoveries!

This is our last chance till Galileo to see this kind of pictorial
history in the making ... I don't expect daily feeds from HST!

                              ... Gavin Eadie, Ann Arbor, Michigan
                                  [e-mail]

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

Date: 2 Aug 89 17:17:16 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Kieran A. Carroll)
Subject: Re: Quick and Dirty Won the Race

[e-mail] (John Obendorfer) writes:

(discussion of spacecpanes versus shuttles versus standard rockets)
> The question becomes, is 1 Orbiter at 1,500,000,000-plus divided by
> 50 missions cheaper than one booster at a cost of X???  It's certain,
> just from empirical evidence, that Soviet expendable boosters are
> more reliable and dependable than the shuttle.
>

Empirical statistics for western launch systems suggest that a
"mature" launcher (ie. after the first ten or so development launches,
and after the more subtle bugs have been eliminated) tend towards
95% reliability, as best as I remember. This is about the reliability
exhibitied by the space shuttle, too (one failure in 24 launches; of
course, we don't yet know the standard deviation on that statistic :-(

Have you any reason to believe that the Soviet launch systems have
any better reliability? I wouldn't be surprised if they were a bit
better, with several thousand launches under their belts. Still,
they've had a number of their cosmonauts die, and had one launch-pad
abort of a manned mission, that resulted in loss of the booster.

The trouble with the shuttle is that when it fails in a big way, an
entire crew dies (when it fails in little ways, redundant subsystems
kick in so that we don't notice). I wouldn't say that the shuttle is
any less reliable than most unmanned launchers, though, nor less
dependable. Now, the >>organization managing<< shuttle launches may
not be as dependable as others...

--

     Kieran A. Carroll @ U of Toronto Aerospace Institute
     uunet!attcan!utzoo!kcarroll [e-mail]

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

Date: 1 Aug 89 19:45:00 GMT
From: m.cs.uiuc.edu!p.cs.uiuc.edu![e-mail]
Subject: Re: Satellites



>Why do you not think he is seeing satellites?  They would be especially bright
>just after dawn and just before sunrise.  Pulsations could come from tumbling
>objects, the periods of which should be very regular (though the best angles
>might only occur temporarily -- so it might appeare erratic.)

The satellites just aren't bright enough.  You can spot Mir easily enough, if
you know where to look (it's no brighter than 4th magnitude), and the old
Echo's were pretty easy, but for something like a spysat, spent booster etc,
you need magnification.

ami silberman, janitor of lunacy

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

Date:       Wed, 02 Aug 89 08:52:14 EST
From: [e-mail]
Subject:    Buying the hottest jet...

I don't know if this will reach you but if it does prune as
necessary and post.
As a Commercial Pilot in Canada I feel more than a little amused
sometimes by the net when people post things that do not match the
rules.  The rules are not the problem but sometimes people not
knowing the rules think there is a problem, so let me give it a kick
at the can.
Rule zero, there are rules.
The countries of the world have decided to give up the power to
make there own policy in exchange for a having the same rules
in force everywhere.  The countries of the world can not decide
to do something without talking to the others.
They then ruled everything that moves off the ground an aircraft.
The next rule was to divide the Aircraft ( A/C ) into two groups called
( in Canada ) "State" and "everybody else".  Each group of A/C has
has rules so lets do both types.
State aircraft are owned by the country, flown by the country,
and have NO DOCUMENTS.  Examples are T-33 jets.
"Everybody else" would be Commercial aircraft, Private Aircraft etc.
If you read the rules closely you will find one of these is a
small metal plate by the door ( plus the rest of the engines,
airframe and other bits) plus documents.
Lets talk Documents ( the real reason you can't fly a T-33 )
A/C have a Certificate of Registration.  Which says "at this time
in the past an approved company following all the rules built this
and it was given this name".  Part of this is a paper from an
approved person saying the thing has been kept up to a standard.
A/C have a Certificate of Airworthess.  Which says "it flyes
like an airplane of it's type".  Plus a paper from an approved
person saying it has been kept up to a standard.
The above makes my point so I will not go on.
An A/C can not be flown till it has an approved person at the
sharp end.  You are given permission based on years of age,
your health, your demonstrated ability TO A COMPETENT OBSERVER.
So lets finish.  You want to fly jet's ( a T-33 ).
1) you are trying to fly a State aircraft! no documents.
This is something the U.S. has agreed with every other country
on the planet they will not do.
2) Document the A/C you say!  How about re-build the thing from
the ground up, it would be less costly.
3) document yourself!  How?  No Approved people exist, no competent
observers exist ( in the not-State aircraft world ).
Let's finish -> -> FORGET-IT <- <-.  Unless you have enough $$$
to re-do the last 40 years of history.   That is what makes rockets
so expensive.

BRIAN

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

End of SPACE Digest V9 #605
*******************