Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_1/V16NO190.TXT

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Date: Wed, 17 Feb 93 05:00:06
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #190
To: Space Digest Readers
Precedence: bulk


Space Digest                Wed, 17 Feb 93       Volume 16 : Issue 190

Today's Topics:
                      Degeneration of sci.space
                   flashlights aboard the shuttle?
             Getting people into Space Program! (2 msgs)
                               ICE Ship
                            Life on Saturn
                    Privatization of space science
                           Question Help !
                         SETI TARGETED SEARCH
                      Shorter Posts => Editing!
                        Space Digest V16 #186
                 SSTO re-entry - cooling and fuel use
                    Wood Pulp/Ice/Landing Strips..

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

Date: Mon, 15 Feb 93 06:26:49 PST
From: Jason Cooper <[e-mail]>
Subject: Degeneration of sci.space
Newsgroups: sci.space

I'm sorry, is this terminal wrong, or is this sci.space?  I seem to
remember, a few months ago, 50+ messages of space-related topic on here
daily, but THIS newsgroup that I've stumbled over has a few per day and
10+ about how the guy who posted the Challenger transcript was an idiot,
or how the guy saying so is an idiot.  Guess I'll talk to my SysOp about
that, because he MUST be screwing up; I know the people in sci.space were
too good to do something STUPID like that.

                                                        Jason Cooper

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

Date: 15 Feb 93 19:47:54 GMT
From: Bruce Watson <[e-mail]>
Subject: flashlights aboard the shuttle?
Newsgroups: sci.space

In article <[e-mail]| [e-mail] (Frank Reid) writes:
|What kind of flashlights are used aboard the shuttle?  Are there
|special NA$A $pace-qualified fla$hlight$, or do they use
|something more mundane?
|
There is a picture of a penlight on page 2.20 of _The Space Shuttle
Operators Manual_, Joels, Kennedy, Larkin, Ballantine Books, NY, 1982,
IBSN 0-345-03021-0. It looks very much like those mundane mini-lights that
are made by a number of manufacturers except that there is a band
of velcro hooks (if you need a flashlight you need to know where it is.)
and the paint has been stripped off (The paint on one of mine has
chipped off in places. I hope those chips didn't make it into my
floppy drive.)

NASA tries to use off-the-shelf components when possible
and adapt them to Shuttle conditions, but if nothing commercial exists
they've go to spend the money to build it.

--
Bruce Watson ([e-mail]) Bulletin 629-49 Item 6700 Extract 75,131

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

Date: 16 Feb 93 01:03:03 GMT
From: Brian Stuart Thorn <[e-mail]>
Subject: Getting people into Space Program!
Newsgroups: sci.space

>If you view the shuttle as a transportation system, it's pretty lousy.
>cargo weight is low.  cost is high.  mission sortie rate is very low.

     Cargo weight is low? The only active system with greater lift
     capacity is Energiya, and Russia isn't planning to launch one
     anytime soon. Sure Saturn 5 was more powerful, but it was hardly
     cheap to fly, either.

>If you view it as a workshop, it's also pretty poor.  8 weeks availability/
>year.  small, cramped.  low power rating.  restricted chemicals.
>Would you want to work at a lab with only one outlet?
>
>the shuttle is a combined workshop/transporter, and hence does
>neither job particularly well.   I think something
>like skylab would be much more useful  with some larger
>resupply vehicles and the capacity to grow the structure.

     It's called "Space Station Freedom".

>If STS was sucha great workshop, why build freedom?

     Once Freedom is operational, Shuttle will no longer be a workshop.

>I don't think wings affect the size of the re-entry vehicle,
>they improve the cross wind landing range.  Wings allow
>the vehicleto go over 2,000 miles left or right of the ground
>track.  this was an AF requirement, not a NASA spec.
>the NASA design for the shuttle was alifting body.

     Actually, most NASA specs were for straight-wing designs. Very
     few lifting bodies in the early Shuttle proposals.

-------------------------------------------------------------------------
Brian S. Thorn                                    "If ignorance is bliss,
[e-mail]                               this must be heaven."
                                                -Diane Chambers, "Cheers"
-------------------------------------------------------------------------

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

Date: 15 Feb 93 18:15:57 GMT
From: Pat <[e-mail]>
Subject: Getting people into Space Program!
Newsgroups: sci.space

In article <[e-mail]| [e-mail] (Gary Coffman) writes:
|In article <[e-mail]> [e-mail] (Pat) writes:
|>I think a better comparison is the SR-71.
|>It gets to australia and back at some fairly cheap price, without
|>major mental problems.  Or the X-15.  it had a fairly substantial
|>cruise range and was defined as a space craft.  Does anyone have
|>any figures on the costs of either the SR-71/hour or the X-15?
|
|I don't have any hard cost numbers, but Mary may. I do know that
|when the SR71 was in military service it didn't take off until
|it's tankers were in the air. I suspect it would need 3 or 4
|refuelings to make it to Australia. The X-15 certainly wasn't
|a long range aircraft, and was not designed for in flight refueling.
|

MARY is the net expert on both of these birds, probably having more
time around the programs then all the rest of us combined.
The SR-71 tanked after takeoff, but that was because the tanks
leaked until warm.   I am not sure if the SR-71 range is still
classified, speed I think still is.  But I'd be surprised if
a 71 couldn't make australia on one tank from LA  the thing used
to fly from turkey to finland  and pakistan deep into china
and back.

|>All comments aside,  I would expect the DC-1 to not cost more then a
|>small multiple of either the SR-71 or X-15.  and to start have
|>a operational record very similiar to either.
|
|I wouldn't be at all surprised either. I expect DC-1 would have about
|the same cost per pound-mile as X-15, updated for inflation.
|

But the X-15 program was put together on a very modest budget.
It was quick off the boards and built and explored space and hardware.
Unlike NASP which has been a drawing board angel since 1983.
I really think project management is almost more important
then technical goals.
|>The X-15 had 3? aircraft built to acquire data and flight characterestics,
|>and aside from some program difficulties. Wrecking one bird, killing
|>an astronaut??? and bending some metal, plus burning some incredible
|>holes in places you'd never expect.
|>
|>I would imagine the X-15 test program should provide a
|>guide to the difficulties of the DC test program.
|
|Yep.
|

BUt the X-15 was a massive success, for a very difficult problem
and it delivered a functionally operational spacecraft.
If the 15 could fly,  why do you seem so sceptical of the
Delta Clipper.  The STS and Fred and NASP seem to be managed
as a welfare project not a product project.

pat
|Gary
>
>--
>Gary Coffman KE4ZV          |    You make it,     | gatech!wa4mei!ke4zv!gary
>Destructive Testing Systems |    we break it.     | uunet!rsiatl!ke4zv!gary
>534 Shannon Way             |    Guaranteed!      | emory!kd4nc!ke4zv!gary
>Lawrenceville, GA 30244     |                     |

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

Date: Mon, 15 Feb 1993 23:22:28 +0000
From: Andrew Haveland-Robinson <[e-mail]>
Subject: ICE Ship
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Gary Coffman) writes:

>>* Zero tankage factor.  Even if we use up 90% of the ice as
>>  propellant, the remaining 10% is usable payload, not tank.
>>  Thus, ice rockets can return massive quantities of ice,
>>  organics, etc. from known Jupiter-family comets to high
>>  Earth orbit, despite the high delta-v.
>
>I don't think this could be called an ice spaceship. That has conotations
>of a vessel carrying a cargo, not of the vessel *being* the cargo. I
>think this falls more under the heading of (minor) planetary engineering.
>What you're doing is changing the orbit of an existing ice planetoid
>using native reaction materials. If the materials are sufficiently pure,
>it would be reasonable to use a steam rocket. If they aren't, a mass
>driver would be better since it doesn't care *what* it throws away,
>just how much it masses. You could then process only what was left that
>was useful at the end of the journey. That would probably result in a
>severalfold reduction in processing requirements.
>
>If orbital transfer time is long, as would be expected in the general
>case, you might be able to do processing in flight and wind up delivering
>*only* processed material at destination. This would likely be the most
>efficient case.

Can't resist this: an interplanetary lollipop! :-)  Surfing the Earth on
reentry could be "environmentally sound", but the ice reaction mass would
have to be jettisoned to reduce energy build-up and producing a meteoric
kettle!

+-----------------------------------------------------------------------+
| Haveland-Robinson Associates   | Email: [e-mail]         |
| 54 Greenfield Road, London     |        [e-mail] |
| N15 5EP England. 081-800 1708  | Also:  0621-88756 081-802 4502       |
+-----------------------------------------------------------------------+
<<>> Those that can, use applications. Those that can't, write them! <<>>
> Some dream of doing great things, while others stay awake and do them <

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

Date: 16 Feb 1993 04:25:16 GMT
From: "Peter T." <[e-mail]>
Subject: Life on Saturn
Newsgroups: sci.space

Recently a friend of mine asked me if I know anything about
life on Saturn {no not interdimensional garb}. Apparently a
friend of a friend of .......   , said something about life being
found on Saturn and heard it on the local news.

Correct me if I'm wrong but if I remember correctly, Voyager 2
detected organic molecules in Saturn's upper atmosphere or
in one of it's rings, and I concluded that thats what this is all
about.

Does anyone know otherwise?

Cheers
Peter T.

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

Date: Tue, 16 Feb 1993 10:16:04 GMT
From: Nick Szabo <[e-mail]>
Subject: Privatization of space science
Newsgroups: sci.space

[e-mail] (Craig Meyer) writes:

>What would happen if a prospective space-services company were to approach the
>governments of the world an offer to bring back a bucket of Mars dirt, along
>with other samples and measurements, to the highest bidder?

There has been some small efforts along these lines with ocean satellite
data, and currently the "Back to the Moon Bill" is promoting this type
of thing.  I support this approach, but we'll need to do quite a bit
of experimenting before it yeilds major improvements.  The problem is,
what kind of data is needed?  Where should that bucketfull of soil come
from?  The scientists want the highest quality bucketfull of soil, not
the cheapest one.  For example, carefully selected bits from dozens of
different sites would be far more valuable than the bucketful that
happens to be underneath the lander.  Using a telescope, or exploring
someplace different like asteroids or comets or the lunar poles might
have been a better use of the money.  Whether that is worth the extra
money has long been a bone of contention, and this scheme does not
solve the fundamental science quality vs. funding tradeoff.

Alas, once government starts setting detailed specs, the advantages
of going private are gone; the contracting becomes "commercial" in
name only.  An industrial example are the proposals to buy "commercial"
HLV flights to resupply SSF.  But all this presupposes that HLVs
and space stations are the way to go, a direction which private
industry itself has not taken.

The biggest advantage private industry brings to the ball game is the
choice of what to do in the first place.  Industry has the motivation
to choose the most productive course; government the most politically
lucrative approach.  Schemes where government pays private industry $X
for service Y undercut the markets's strengths by forcing political
choice Y on industry, where market choice Z might have been a far
more productive use of $X.

If someone could figure out a way for government to follow the lead
of industry in funding the market's choices, we could come up with
a winning way for government to boost the space program.
Unfortuneately, government politicians and agencies, and even morer
unfortuneately many space fans, seem to thrive on criticizing "market
failures" rather than taking the time to learn what industry is actually
doing, and how the government might help along that process.


--
Nick Szabo                     [e-mail]

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

Date: 15 Feb 93 20:04:45 GMT
From: Bruce Watson <[e-mail]>
Subject: Question Help !
Newsgroups: sci.space

In article <[e-mail]| [e-mail] (Rich Kolker) writes:
|I can't believe there has been so much trouble on this.
|
|The first American wonman to walk in space was Kathy Sullivan.  The
|first woman to walk in space was Svetlana Savitskaya.
|
Saviskaya in July of 1984 and Sullivan in October of 1984.
--
Bruce Watson ([e-mail]) Bulletin 629-49 Item 6700 Extract 75,131

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

Date: Mon, 15 Feb 1993 23:08:42 +0000
From: Andrew Haveland-Robinson <[e-mail]>
Subject: SETI TARGETED SEARCH
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Francisco da Fonseca Rodrigues) writes:

>    Could someone send me, by email, the list of stars in SETI Targeted
>Search? I know this subject is related to sci.astro, but I don't know the
>eletronic address of this list.
>

Talking of which, is Sirius A, B and C targeted?

Andy.


+-----------------------------------------------------------------------+
| Haveland-Robinson Associates   | Email: [e-mail]         |
| 54 Greenfield Road, London     |        [e-mail] |
| N15 5EP England. 081-800 1708  | Also:  0621-88756 081-802 4502       |
+-----------------------------------------------------------------------+
<<>> Those that can, use applications. Those that can't, write them! <<>>
> Some dream of doing great things, while others stay awake and do them <

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

Date: 16 Feb 93 10:01:34 GMT
From: Del Cotter <[e-mail]>
Subject: Shorter Posts => Editing!
Newsgroups: sci.space

[e-mail] writes:
>Can people please change the subject of a post if the post/answer/reply has
>definitely changed the meaning since the original post..

Also, please learn to edit down the post you are replying to.

>I read quite a few posts at my normal 1200 baud and it takes forever to weed
>thru some 100 post (50 if I call every day), I also check a few other
>newsgroups and I can read some 50 to 200 messages a night..

Then shame on you, Michael, for burdening other people.  You quoted
'Spaceships made of Ice' *in full*, only to add a mere four lines of
comment.

Not a flame, honest.  I agree with what you are saying.
--
 ',' ' ',','  |                                                  |  ',' ' ',','
   ', ,','    |       Del Cotter       [e-mail]      |    ', ,','
     ','      |                                                  |      ','

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

Date: Tue, 16 Feb 93 08:52:15 EST
From: Bill Collins <[e-mail]>
Subject: Space Digest V16 #186

>Posted on 15 Feb 1993 at 18:04:59 by Space Digest maintainer
>
>        There's another Meteor Crater in West Texas near Odessa, just off
>Interstate 20. That one's not much of a tourist attraction.... just a 100-yard
>across disturbed area. Rather severely asthetically damaged by the trenches
>dug in it by curious geologists who didn't bother to clean up after themselves,
>unfortunately. Still worth a visit if you're in the area, if only to see
>oil pumpers going right next to a meteor crater!

Trenches not withstanding, the construction backfill poured into the crater
and then smoothed over probably accounts for some of the disturbed area and
accounts for a lot of the aesthetic damage.

                                       Bill

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

Date: Tue, 16 Feb 1993 07:13:30 GMT
From: Henry Spencer <[e-mail]>
Subject: SSTO re-entry - cooling and fuel use
Newsgroups: sci.space

In article <1993Feb15.145207.15108@bsu-ucs> [e-mail] (Craig Meyer) writes:
>I suppose an SSTO would have heat shielding on the bottom.  Whould it me
>made of the same ceramic material as the space shuttle tiles?

Depends on how the SSTO is built.  The Delta Clipper design reenters nose-
first and uses (mostly) high-temperature alloys for its thermal protection.
General Dynamics' unsuccessful rival design reentered base-first and used
liquid hydrogen cooling of the base area.

>Does heat shielding
>contribute significantly to wieght?  To cost?  To complexity?

Yes, yes, and yes.

>Would this be a better way to cool a landing SSTO?
>Through the bottom surface and engine nozzles, circulate a fluid (like H, He,
>or H2O).  Once the fluid is done cooling the craft, it will be very hot and
>under great pressure.  Therefore, shoot it out the back and develop thrust...

This sort of once-through liquid cooling has been a staple of wingless
SSTO design concepts for 20-30 years, in fact.  You can't get any useful
amount of thrust out of it -- the stuff doesn't get *that* hot -- but
it's a reasonable cooling approach for the short-and-sharp heat loads
found in wingless reentries.  Liquid hydrogen is preferred, although
water might also be usable (it doesn't start out as cold but its
heat capacity is very high).

>...  Also, if a hydrocarbon fuel were
>used, would using a different fluid to cool the craft/engines prevent coking
>(collection of solid carbon in the tubing)?

People have investigated using liquid hydrogen for cooling in an engine
that basically burns hydrocarbons, for exactly this reason.  It would
work.  However, it is not clear that it's worth the trouble.
--
C++ is the best example of second-system| Henry Spencer @ U of Toronto Zoology
effect since OS/360.                    |  [e-mail]  utzoo!henry

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

Date: 15 Feb 93 15:18:49 GMT
From: Gerald Edgar <[e-mail]>
Subject: Wood Pulp/Ice/Landing Strips..
Newsgroups: sci.space

There was a effort to create mid-ocean refueling stations in WWII. The
idea was to create an iceberg made of wood chips and ice as a cheap aircraft
carrier (no propultion of course). It was tried off Greenland, it worked,
but it turned out not to be needed later- when the planes could be flown
non-stop trans-atlantic. By the way, they also tested this for munitions
effects, torpedos had little effect, making only small dents.
I do not remember the source for this information.

Gerald Edgar
"My opinions are my own, not my employers"

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

End of Space Digest Volume 16 : Issue 190
------------------------------