Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v15_0/v15no075.txt

Text File | 1993-07-13 | 29KB | 702 lines

Date: Thu,  6 Aug 92 05:01:49
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #075
To: Space Digest Readers
Precedence: bulk


Space Digest                Thu,  6 Aug 92       Volume 15 : Issue 075

Today's Topics:
                A 12 mile tether that generates 5000v?
          Energiya's role in Space Station assembly (2 msgs)
                      Galileo Update - 08/05/92
                    Hipparcos Emergency - 08/05/92
                          Home made rockets
            Loose nukes  (was Re: Clinton Space Position)
                     More second-hand info on TSS
                        Origin of Life article
             Random Notes (Was Re: NASP, NLS, SSTO, etc.)
                        Soyuz as ACRV (6 msgs)
                             SSF (2 msgs)
                            What is FRED?
                       What is FRED?? (2 msgs)

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Date: 4 Aug 92 18:03:17 GMT
From: Bruce Watson <[e-mail]>
Subject: A 12 mile tether that generates 5000v?
Newsgroups: sci.space

In article <[e-mail]| [e-mail] writes:
|or even megawatts of power could be generated (at the expense of orbital
|angular momentum, of course).

Which is enormous, BTW.

|--
|Mike Matthews, Tether Dude    +------------->   [e-mail]
|"Got the Shuttle on a String"  \_ Now accepting NeXTMail via KlugeNet(TM)!
|Lockheed-ESC                  |
|Houston, TX                   |          *** WILL HACK FOR FOOD ***


--
 __________________________________________________________________________
|[e-mail]|    "Another Case of too many scientists and     |
|Bruce Watson            |     not enough hunchbacks." -- Gary Larson      |

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

Date: 5 Aug 92 12:36:54 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Energiya's role in Space Station assembly
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
>
>Someone else brought up the question of shipping Energias to KSC. The Anotonov
>225 transporter, the largest cargo place yet, was specifically designed to
>shift chunks of Energia around, so you could just fly them in to KSC. Rather
>easier than barging them in as we are told happened with the SV.

Barging is easy, cheap, and off the shelf. It's a much superior method
for bringing a Saturn sized rocket to the Cape than a specially built
aircraft. Of course if pork barrel politics wasn't such an issue, the
rocket factory would have been *at* the Cape in the first place. NASA
is scattered all over the country for only one reason, political back
scratching.

Gary

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

Date: Wed, 5 Aug 1992 16:28:05 GMT
From: Henry Spencer <[e-mail]>
Subject: Energiya's role in Space Station assembly
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Gerald Cecil) writes:
>... Finally, how does the shielding on the
>Space Station compare to that on Skylab (which flew at 55+ degs)?  True,
>Skylab was occupied during a solar Min (the next Max is what nailed it), but
>was radn shielding a real concern?

To some extent.  No special efforts were made to shield the crew, that I'm
aware of, but note that the longest planned mission was only 90 days.  The
single biggest and heaviest component aboard Skylab -- source of some
concern when Skylab came down -- was a massive safe used to shield Skylab's
supply of photographic film.
--
There is nothing wrong with making      | Henry Spencer @ U of Toronto Zoology
mistakes, but... make *new* ones. -D.Sim|  [e-mail]  utzoo!henry

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

Date: Thu, 6 Aug 1992 00:10:42 GMT
From: Ron Baalke <[e-mail]>
Subject: Galileo Update - 08/05/92
Newsgroups: sci.space,sci.astro

Forwarded from:
PUBLIC INFORMATION OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109.  TELEPHONE [phone]

                     GALILEO MISSION STATUS
                         August 5, 1992

     The Galileo spacecraft is 174 million kilometers (108
million miles) from Earth, and about 259 million kilometers from
the Sun.  Its speed in orbit is 21,630 meters per second, more
than 48,000 mph.  It is operating normally and transmitting coded
telemetry at 40 bits per second.

     This week the spacecraft is using the onboard propulsion
subsystem to change its trajectory for the fourteenth time since
launch.  It is pulsing its tiny thrusters more than 5400 times
over a four-day period.  On Monday, August 3, a routine
propulsion-system maintenance activity "flushed" the thrusters.
The same day, the thrusters were fired to orient the spacecraft
for the maneuver.  Tuesday at about 7:00 a.m. PDT Galileo began
the first portion of the maneuver, to change its velocity by
about 6.2 meters per second.  Similar maneuver portions are
occurring today and Thursday, August 6.  On Friday at about 11:30
a.m. PDT the fourth portion will conclude; Galileo's velocity
will have changed by about 21 meters per second (47 mph).

     The flight team designed this maneuver as the first in a
planned series to set up and refine the second Earth gravity
assist on December 8, 1992, taking into account the Asteroid Ida
encounter, now approved and scheduled for August 1993.

                              #####
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | You can't hide broccoli in
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | a glass of milk -
|_____|/  |_|/       |_____|/                     | anonymous 7-year old.

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

Date: 6 Aug 92 00:07:32 GMT
From: Ron Baalke <[e-mail]>
Subject: Hipparcos Emergency - 08/05/92
Newsgroups: sci.space,sci.astro

                       HIPPARCOS SPACECRAFT EMERGENCY
                            August 5, 1992

     ESOC (European Space Operations Center) declared a spacecraft emergency
on the Hipparcos spacecraft on August 4 at 1424Z.  The project reported that
the prime AOCS (Attitude Orbit Control System) had failed.  DSS-16 (the
26 meter antenna in Goldstone, California) was configured for support and
was on point at 1445Z.  After further analysis of the spacecraft condition,
the project reported the backup AOCS was working.  Hipparcos is in a sun
acquisition mode and will remain in this mode until further analysis of the
problem on the prime AOCS.  The project lifted the spacecraft emergency at
1830Z on August 4.  DSS-16 continued tracking until the end of the
scheduled support at 0006Z on August 5.
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | You can't hide broccoli in
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | a glass of milk -
|_____|/  |_|/       |_____|/                     | anonymous 7-year old.

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

Date: 5 Aug 92 19:36:06 GMT
From: [e-mail]
Subject: Home made rockets
Newsgroups: sci.space

I have recently got into the field of making home-made rockets and have been
experimenting with various types of cheap, readily availible fuels and
cannisters. We have found that the best rockets to date are made of salt peter
and castor sugar, mixed in a half, half ratio. This is then heated to melting
point and spooned into container.

The best launch went to about 250m for 100gms of ingredients. Launch sites have
proved to be a bit of a problem as with the current state of political affairs
here, we are a touch scared of being arrested.

If anyone has any new/different ideas for fuels, chemical components, homemade
flares, please let me know.

Thanks

Mike

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

Date: Wed, 5 Aug 92 16:32:22 BST
From: [e-mail]
Subject: Loose nukes  (was Re: Clinton Space Position)

Enjoyed the conference quite a bit. Also gave me a chance to make a
trip to Pittsburgh to see family & friends & my old coworkers at CMU.

The details are BTW that a pair of 3-5KT nuclear artillery shells,
sans activation codes, were tracked from a depot in Kazakhistan to
Iran. A third shell of similar type is still missing.

They are sophisticated moderen weapons but can probably not be used
as is because they cannot be armed. But they can be reverse
engineered and the fissionable material can be reused.

Th article indicated that the CIA and KGB had cooperated in tracking
them down.

There were indications that the leadership of Kazakhistan may have
sold them in return for Iranian oil, but did the whole thing in a
plausibly deniable way. The weapons are small enough that they could
have been driven across the border in the back seat of a volkswagon.

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

Date: 5 Aug 92 15:54:20 GMT
From: Mark Bixby <[e-mail]>
Subject: More second-hand info on TSS
Newsgroups: sci.space

I was monitoring shuttle air-to-ground on my scanner this morning at 0700 PDT
8/5/92 and at that time the TSS had been deployed to a length of 800 (feet?
meters?).  Attempts at increasing the length kept failing, due to the vernier
motor at the end of the boom failing to maintain tension on the tether.  An
intermittent clutch failure is suspected.
--
Mark Bixby                         Internet: [e-mail]
Coast Community College District   1370 Adams Avenue
District Information Services      Costa Mesa, CA, USA  92626
Technical Support                  [phone]
"You can tune a file system, but you can't tune a fish." - tunefs(1M)

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

Date: Wed, 5 Aug 92 11:44:50 EDT
From: Steve Troxel <[e-mail]>
Subject: Origin of Life article

Why is it so difficult for people who call themselves
scientists to explore the possibility that God created the
earth and all the creatures on it?  There is every bit as much
scientific "proof" for the "theory" of creation as there is for
the "theory" of evolution.  Why is everyone so set against
acknowledging a valid alternative hypothesis?  Is there some
prejudice against is?

Steve Troxel
[e-mail]

**Save the baby humans.**

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

Date: 5 Aug 92 14:27:26 GMT
From: [e-mail]
Subject: Random Notes (Was Re: NASP, NLS, SSTO, etc.)
Newsgroups: sci.space,sci.aeronautics

In article <[e-mail]>, [e-mail] writes:
> In article <[e-mail]>, [e-mail] (John A. Weeks III) writes:
>> While driving into the parking lot at the USAF Museum in Dayton on Monday,
>> I saw an X-30 mock-up departing Wright-Patterson AFB on the back of a
>> semi-truck.  It was painted white and blue with red trim.  Since the plane
>> was about 40 feet long, I suspect that it was a 1/3 scale mock-up.
>                                                   ^^^^^^^^^^^^^^^^^
>
> You are correct.  This model was made by senior engineering students
> at Mississippi State University for NASA and the NASP JPO.  It should
> be at the AF Museum until the end of August (I can get the exact date
  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Whoops!  I slipped a month.  The 1/3 scale model of the NASP left at
the end of July to go to the Oshkosh Air Show.  It is either en route
or at the Ohio State Fair now.  It will be at the World Space Congress
later on.

> if you are interested).
>
> P.S.  I am one of the people they roped in to 'man' the NASP booth
> at the U.S. Air and Trade Show, so if you have any questions feel
> free to ask.
>
> --
>
>    Jim Batka  | Always remember ...                        | Buckaroo
>    Modemman   |    No matter where you go, there you are!  |   Bonzai
> --------------+--------------------------------------------+--------------
>               | Work Email:  [e-mail] | Elvis is
>               | Home Email:  [e-mail]      |   DEAD!
> --------------+--------------------------------------------+--------------
>               | 64 years is 33,638,400 minutes ...         | Beatles:
>               |    and a minute is a long time.            |   Yellow Submarine
--
ditto

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

Date: Wed, 5 Aug 1992 15:14:54 +0000
From: Anthony Frost <[e-mail]>
Subject: Soyuz as ACRV
Newsgroups: sci.space


  >> So we add another one. Multiple Soyuz is actually an
  >> advantage. First of all, it prevents single point failure.
  >> Suppose the module which connects to the ACRV is on fire and
  >> needs to be quickly closed down or is suffers major
  >> structural failure. The way it is now, the crew would have
  >> no way out. With two Soyuz, they could all pile into one,
  >> maneuver to the other and do an EVA to transfer the extra
  >> crew.

  > So you're going to fit 6-8 people, plus at LEAST one suit
  > plus beachballs into the Soyuz, in a capsule which fits
  > three men uncomfortably?

So that makes a case for leaving the orbital module on the Soyuz. Lockers
for descent pressure suits, EVA suit and beachballs and space for extra crew
members during transfer operations. In fact with sexless docking adaptors as
long as the second Soyuz could be undocked from Fred no EVA would be needed?

          Anthony

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

Date: Wed, 5 Aug 1992 15:14:54 +0000
From: Anthony Frost <[e-mail]>
Subject: Soyuz as ACRV
Newsgroups: sci.space

  > I'd like to see a Soyuz:

  > (a)  Stay up for two weeks for large-scale biomedical
  > studies.

I'm not sure of durations, but I beleive several pre-Salyut Soyuz's did just
that?

        Anthony


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

Date: 5 Aug 92 10:27:58 EDT
From: "John F. Woods" <[e-mail]>
Subject: Soyuz as ACRV
Newsgroups: sci.space

[e-mail] (Henry Spencer) writes:
>>Furthermore, both "rescues" were simple; i.e.; hit one docking adaptor, go
>>inside, do whatever. With a shuttle, you could use the CanadaArm ...
>> to grab onto the truss or use to remove/replace/restore a flapping
>>solar panel.
>Much like the way the first Skylab crew deployed a sunshade and then freed
>and deployed the surviving main solar array.  Nice though the arm is,
>I'll take men in spacesuits over it any day when the job gets tricky.

And oddly enough, the professionals seem to agree, as anyone who watched
the Intelsat rescue should know...

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

Date: Wed, 05 Aug 92 16:23:01 GMT
From: Doug Mohney <[e-mail]>
Subject: Soyuz as ACRV
Newsgroups: sci.space

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

>>If you had your choice of [shuttle] verses a 3 man shot with limited
>>supplies, tools, no CanadaArm, which would you choose?
>
>The one with a better chance of success, which is probably the shuttle.
>But how many 3-man shots can you launch for the cost of running the
>shuttle for one year?  If I had my choice between three attempts using
>3-man capsules, and one using the shuttle, I know which I'd pick.

>I note, also, that we have changed the subject:  the claim that it just
>can't be done using capsules has quietly been dropped.

Since you can't define the failure/disaster mode of what might happen to
Freedom, I choose to define the failure mode of Freedom as something which
would require extensive resources to repair and beyond the capability of a tin
can. :-) (By golly, it's nice to be an Imperialist!)

Being able to fill up the Shuttle bay with an CanadaArm <MapleLeaf and all>,
consumables, MMU, and having significant maneuver capability in orbit strikes
me as being able to handle more situtations. That there Soyuz isn't known for
it's dancing capability, is it, hmm?

>Much like the way the first Skylab crew deployed a sunshade and then
>freed and deployed the surviving main solar array.  Nice though the
>arm is, I'll take men in spacesuits over it any day when the job gets
>tricky.

EVA is a last resort. Come come, even you know that.

>>Of course, if we went tin-can, we could leave the CanadaArm home and cut back
>>Canadian participation in the United States space program.
>
>Tsk tsk, you're showing your ignorance.  We participated in the earlier
>programs too (although in still smaller ways).

Tsk tsk, I guess you need a better press agent or a bigger contribution before
you toot yer horn so loudly.



                 Support U.N. military force against Serbia

  -- >                  [e-mail]                        < --

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

Date: 5 Aug 92 16:47:31 GMT
From: "Robert A. Lentz" <[e-mail]>
Subject: Soyuz as ACRV
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:

    [Lots of discussion about Fred doing the same on-orbit
        tasks as shuttle deleted.]

Have the concerns for polluting the environment surrounding the station
been removed? If not then would not a lot of this on-orbit processing, and
the frequent Soyuz flights do much to polluting the environment?

And the frequent soyuz flights would still put a cap on the duration of
some of the microgravity experiments. (Though I am not certain what the
maximum time between reboosts can be either...and always thought anything
other than a free-flyer for the micro-gravity work was kind of stupid.)

And last I knew, the proposal still called for refurbishment by swapping
modules as the shuttle carried them up. I have heard how they would be
carried up on the HLV Delta, but how would they be returned?

(Perhaps I missed a lot in the latest redesign...)

Thanks,
-Robert
--
[e-mail]      "We're a rock-and-roll band and we'll bring down the house
                   the way Bill is going to bring down the country."
                       -Roger Clinton, on his band's plans to play at the
                        Inauguration if his half brother, Bill, wins.

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

Date: 5 Aug 92 16:47:18 GMT
From: Henry Spencer <[e-mail]>
Subject: Soyuz as ACRV
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
>By the way someone here stated that COMET could return 750 kg. That is not
>true, COMET Weighs 750 kg. The return capsule payload is only 60 kg.

As I said, I haven't seen specs for COMET itself, only for some of the
proposals that went into COMET planning...

But even ignoring that, note that I didn't say that *COMET* had a 750kg
return capability.  I said that its *capsule* had such a capability.
Unless COMET has changed radically since the early proposals, only a
fraction of the mass that comes down in its capsule actually counts as
payload.  But most of the extra is things that aren't needed for a
dedicated payload-return capsule.

The way you make things cheap and efficient is to design them to do one
mission and do it well.  For example, transporting astronauts to/from
orbit and supporting them for long stays while there are two different
missions that should be done by different equipment; orbiter plus Spacelab
is an insanely inefficient way to do this, if only because of all the mass
that gets hauled up at great cost only to be brought down again a week
or two later.  More to the current point, the vast majority of payload-
return requirements -- real ones, not imaginary ones -- can be met with
a simple, small, cheap expendable return capsule.
--
There is nothing wrong with making      | Henry Spencer @ U of Toronto Zoology
mistakes, but... make *new* ones. -D.Sim|  [e-mail]  utzoo!henry

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

Date: 5 Aug 92 10:36:37 GMT
From: Nick Szabo <[e-mail]>
Subject: SSF
Newsgroups: sci.space

This thread has hit on a very important issue, but it beats around the bush.
The fundamental problem is that a large "stepping stone" or "centerpiece"
of "the space program" will by its very nature be in the wrong orbit.   If
we choose 28.5 degrees, we lock out participation by the Soviet launch sites
and the largest users of space, our military in polar orbit.  If we put it
at 50 degrees the penalty for using it as a "way station" to Clarke orbit,
the Moon, Mars, or asteroids is prohibitive.  In turn, 28.5 degrees still
puts a significant penalty over going straight to Clarke orbit, the Moon or
Mars. If we put it in polar orbit, it is useful for the military and
climate monitoring, but useless as a way station, and we can't get to it
from Canaveral.

This, among other reasons, is why military and commercial users have
thrown out the concept of a hyper-centralized "space station" in favor
decentralized networks of standardized satellites: constellations.  These
small platforms are launched into orbits specific to the application
at hand, instead of pretending they can open up the solar system from
one orbit.   Communiations platforms ive in Clarke and Molniya, GPS/Navstar
lives in 12-hour orbits, spysats and Mission to Planet Earth live in polar
orbits, etc.   It's time for the space activist community to catch up with
the space users; it's time to redesign our visions to fit the physical
reality of working in space.


--
[e-mail]  Public Access User --- Not affiliated with TECHbooks
Public Access UNIX and Internet at [phone] (1200/2400, N81)

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

Date: 5 Aug 92 15:27:36 GMT
From: "Allen W. Sherzer" <[e-mail]>
Subject: SSF
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Nick Szabo) writes:


>thrown out the concept of a hyper-centralized "space station" in favor
                             ^^^^^^^^^^^^^^^^^^

Not only that, but the problem is getting worse. Space stations used
to be centralized. Now they are "hyper-centralized". What's next?
:-):-):-):-):-):-):-):-):-):-):-):-):-):-):-):-):-):-):-):-):-):-):-)

  Allen
--
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "If they can put a man on the Moon, why can't they     |
|  [e-mail]     |  put a man on the Moon?"                               |
+----------------------261 DAYS TO FIRST FLIGHT OF DCX----------------------+

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

Date: 5 Aug 92 16:53:20 GMT
From: "Robert A. Lentz" <[e-mail]>
Subject: What is FRED?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (John Roberts) writes:
>
>-From: [e-mail] (Henry Spencer)
>-Subject: Re: What is FRED??
>-Date: 4 Aug 92 22:34:02 GMT
>
>-In article <[e-mail]> [e-mail] (Michael Corvin) writes:
>->What program does "fred" refer to?  I've seen it mentioned quite
>->a bit but have never come across what it actually is...
>
>-It's a cynical nickname for Space Station Freedom, coined when the thing
>-shrunk yet again a couple of years ago.
>
>Actually, somebody on sci.space suggested "Fred" even before Reagan announced
>the name "Freedom".

As I recall it was proposed back during a discussion about naming the new
shuttle. It was pointed out that we have Atlantis, Colubia, and Discovery,
so the new shuttle name should begin with a "B". Someone then suggested the
pair of Fred and Barney for the station and shuttle. Someone else suggested
Darwin' ship "Beagle", commenting that it sort of even looks like one :-)

-Robert
--
[e-mail]      "We're a rock-and-roll band and we'll bring down the house
                   the way Bill is going to bring down the country."
                       -Roger Clinton, on his band's plans to play at the
                        Inauguration if his half brother, Bill, wins.

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

Date: 5 Aug 92 10:33:09 EDT
From: "John F. Woods" <[e-mail]>
Subject: What is FRED??
Newsgroups: sci.space,sci.space.shuttle

[e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (Michael Corvin) writes:
>>What program does "fred" refer to?  I've seen it mentioned quite
>>a bit but have never come across what it actually is...
>It's a cynical nickname for Space Station Freedom, coined when the thing
>shrunk yet again a couple of years ago.

Here I fear I must disagree with my esteemed colleague; when the "Name the
Space Station" contest was still on, someone on USENET here suggested "Fred",
amidst immediate acclaim and a discussion of how many computer programs seem
to use "fred" as the name of temporary variables.  When the name Freedom was
chosen, someone observed that this was merely the Government padding the real
name (Fred), much as it has done with Fred's budget.  Then, when Freedom shrank
to the point that there was only name to paint the word "Fred" on it :-), the
name resurfaced and stuck (here, anyway).

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

Date: 5 Aug 92 16:48:01 GMT
From: Saltheart Foamfollowe <[e-mail]>
Subject: What is FRED??
Newsgroups: sci.space,sci.space.shuttle

[e-mail] (Henry Spencer) writes:

> In article <[e-mail]> [e-mail] (
> >What program does "fred" refer to?  I've seen it mentioned quite
> >a bit but have never come across what it actually is...
>
> It's a cynical nickname for Space Station Freedom, coined when the thing
> shrunk yet again a couple of years ago.

To further explain, as the original name is Freedom, Fred is the same
name, but resized to fit the new bulkhead dimensions...

+-----------------------------------------------------------------------+
| Real Life:  Adrian Zannin            |  Riker: "Looks like he died in |
|  Internet:  [e-mail] |          his sleep."           |
|       CIS:  75360,630                |                                |
|--------------------------------------|   Worf: "What a horrible way   |
|    >  This space for rent <          |          to die."              |
+-----------------------------------------------------------------------+

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

Date: 
P
From: 
P

From: Bruce Watson <[e-mail]>
Newsgroups: sci.space
Subject: Re: Energiya's role in Space Station assem
Message-Id: <[e-mail]>
Date: 5 Aug 92 05:02:42 GMT
References: <[e-mail]| <[e-mail]+ <[e-mail]-
Organization: Alpha Science Computer Network, Denver, Co.
Lines: 42
Sender: [e-mail]
Source-Info:  Sender is really [e-mail]

In article <[e-mail]| [e-mail] (Hugh D.R. Evans) writes:
|
|
|In article <[e-mail]+, [e-mail]
|(Gerald Cecil) says:
|+
|+So, my question: why is the Space Station being assembled in a 28.5 deg.
|+orbit?  This locks out ANY participation by the CIS launch complexes for only
|+a few % gain in payload.  (This also excludes the obvious benefit to earth
|+observations of an orbit at 40+ degs, perhaps an important selling point to
|+soon-to-be VP Gore.)  Concerns re abort sites are irrelevant, in that NASA
|+has happily launched Shuttles to higher inclination orbits in the past.
|
|One reason I can think of that FRED isn't going into a 40+ degree
|inclination is the trapped proton fluxes that it would encounter going through
|the South Atlantic Anomaly ( maximum fluxes at ~ -40 deg west,
|-35 deg south).  At a 28 degree inclination, the space station only slightly
|dips into the Anomaly.  The total radiation dose received by a man
|inside a 4mm sphere of Aluminium ( SSF's skin will be about that thick)
|is 17 rads over a 30 day period, compared to 25 rads at a 40 degree
|inclination; requiring an extra 6 mm of Al over the entire surface of the
|space station in order to reduce the dosage to that of the 28 degree
|inclination orbit.  This represents quite a considerable mass increase.

What is Mir's skin thickness? Cosmonauts who have spent up to and including
a year on board at an inclination of 51.6 degrees don't seem to have
been bothered by radiation.

|
|Regards,
|Hugh Evans.
|
|ESTEC, ESA              * Inet:   [e-mail]
|P.O. Box 299            *     or  [e-mail]
|2200 AG Noordwijk       * SPAN:   ESTCS1::HEVANS
|The Netherlands         * BITNET: HEVANS@ESTEC


--
 __________________________________________________________________________
|[e-mail]|    "Another Case of too many scientists and     |
|Bruce Watson            |     not enough hunchbacks." -- Gary Larson      |

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

End of Space Digest Volume 15 : Issue 075
------------------------------