Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT_ZIP/spacedig/V16_3/V16NO334.ZIP/V16NO334

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Date: Thu, 18 Mar 93 05:43:19
From: Space Digest maintainer <[e-mail]>
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Subject: Space Digest V16 #334
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Space Digest                Thu, 18 Mar 93       Volume 16 : Issue 334

Today's Topics:
             Flight time comparison: Voyager vs. Gallileo
                      How to cool Venus (2 msgs)
                            Launch Windows
                            NASA Paperwork
                      plans, and absence thereof
                   What do we do now with Freedom.
                 Winding Trails from Rocket Launches
                            Without a Plan

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Date: Thu, 18 Mar 1993 05:37:45 GMT
From: Eric H Seale <[e-mail]>
Subject: Flight time comparison: Voyager vs. Gallileo
Newsgroups: sci.space

[e-mail] (Ron Baalke) writes:

>Also, comparing Ulysses to Galileo is like comparing apples to oranges.

A true master of understatement! :-)

>Ulysses is a flyby mission, Galileo is an orbiting mission.  Ulysses
>required a very fast trajectory to Jupiter so that is can use
>Jupiter's gravity to be deflected out of the ecliptic plane. Galileo,
>on the other hand, has to approach Jupiter at a more leisurely velocity
>to go into orbit around the planet.

Also, Galileo is carrying much more science (scan platforms aren't
exactly light) than Ulysses (just particles & fields sensors, as I
recall).  And (if memory serves) Ulysses is a spinner; Galileo is
dual-spin (one of the ugly trade-offs resulting from all its
instruments) -- spinners are much simpler, and generally quite a bit
lighter.

To put things in perspective for those who've tuned in, Ulysses started
out life as "Solar Polar" -- twin spacecraft, one European and one
American.  These were originally planned to be launched together in a
"stack" on Shuttle / IUS.  When NASA pulled out (budgetary woes, you
know...), the US bird was replaced by, well, ballast -- to keep the
trajectory right.

So, starting with the same launch approach (Shuttle / IUS), a messy
3-pass grav assist (eventually) gets Galileo to Jupiter with low approach
velocity.  Meanwhile, a direct approach (less efficient, in propulsion
terms) would have taken TWO "Ulysses'" to Jupiter with HIGH approach
velocity.

The crux of this -- Ulysses is much simpler than Galileo, and MUCH
smaller / lighter.

My $0.02

Eric Seale
#include <disclaimer.std.>

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

Date: 18 Mar 93 06:05:00 GMT
From: Callec Dradja <[e-mail]>
Subject: How to cool Venus
Newsgroups: sci.space

When the question of terraforming Venus comes up, it
seems that there are two main problems: one, how to cool
the planet down and two, how to provide water. Most people
begin with the problem of the ultradense greenhouse atmosphere
and immediately think of using some sort of photosynthetic
process to turn the carbon dioxide into oxygen.

The problem with this proposal is that the mechanism by which
plants turn carbon-dioxide into oxygen is to incorporate the
carbon into their structure. For instance, long ago on Earth
there were some organism that through photosynthesis removed
carbon from the atmosphere and incorporated it into their bodies.
When these organisms died, they either fell to the floor of the sea
or they were buried in a peat bog. Through time, the organisms
were converted into either oil or coal. As things now stand, the
Earth has a rather pleasant oxygen rich atmosphere, but if we were
able to dig up all of the coal and oil and burn ALL of it, the
Earth would be uninhabitable by oxygen breathers. You see, the
carbon is removed from the atmosphere only when the organisms are
removed from the atmosphere and neither rot nor are burned.

With Venus we have a problem. If we were to release some sort of
tiny photosynthsizing organisms into the Venusian atmosphere, they
might be able to remain aloft long enough to convert carbon-dioxide
into oxygen but ultimately they would fall to the surface of the
planet. Upon reaching the surface, the dead creatures would be
exposed to temperatures hot enough to melt lead and also hot enough
to turn the creatures bodies bach into carbon-dioxide thus producing
no net effect.

It can thus be seen that the solution to the greenhouse problem
on Venus cannot be solved by photosynthsis. What I propose is to
cool the planet first by means of 'nuclear winter'. Well, not
actually nuclear winter but something similar. What if we were to
release some sort of dust in orbit around the planet? We would use
some sort of dust that would remain fairly reflective and not darken
upon exposure to radiation. The idea is that through careful release
of dust, we would be able to block  a sufficient ammount of sunlight
to cool the planet.

Now that we hopefully have a cooler Venus we need water. Actually
in the hyper dense venusian atmosphere we have plenty of oxygen, what
we actually need is hydrogen. I am not sure if it would make more
sense to import water or hydrogen, but one of the two would be needed
before further terraforming could continue.

If we then had a sufficiently wet and cool atmosphere, then the
importation of either algea or moss could begin. What do the other
readers of this group think? Do you see any holes in my ideas?

Gregson Vaux

********************************************************************
* If all we do is live and die,           *  Gregson Vaux          *
* then tell me about the birds that fly.  *  Penn State University *
* If all we did was die and live,         *  Semitics & English    *
* would springtime be there to forgive?   *  [e-mail]  *
********************************************************************

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

Date: 18 Mar 93 08:29:41 GMT
From: [e-mail]
Subject: How to cool Venus
Newsgroups: sci.space

In article <[e-mail]> Callec Dradja
<[e-mail]> writes:
>
>The problem with this proposal is that the mechanism by which
>plants turn carbon-dioxide into oxygen is to incorporate the
>carbon into their structure. For instance, long ago on Earth
>there were some organism that through photosynthesis removed
>carbon from the atmosphere and incorporated it into their bodies.
>When these organisms died, they either fell to the floor of the sea
>or they were buried in a peat bog. Through time, the organisms
>were converted into either oil or coal. As things now stand, the
>Earth has a rather pleasant oxygen rich atmosphere, but if we were
>able to dig up all of the coal and oil and burn ALL of it, the
>Earth would be uninhabitable by oxygen breathers. You see, the
>carbon is removed from the atmosphere only when the organisms are
>removed from the atmosphere and neither rot nor are burned.

This removing of carbon from primordial atmosphere as a byproduct of the
chemical processes driven by living organisms is a minor cause to present-
day lack of carbon dioxide in our atmosphere. The main deposit of carbon
dioxide in our planet lies in the carbonate rocks which contain some
100,000 times more CO2 than the atmosphere. CO2 is recycled through
plate tectonics and volcanism.

>Now that we hopefully have a cooler Venus we need water. Actually
>in the hyper dense venusian atmosphere we have plenty of oxygen, what
>we actually need is hydrogen. I am not sure if it would make more
>sense to import water or hydrogen, but one of the two would be needed
>before further terraforming could continue.

When considering that almost all of the mass of water lies in the
oxygen atoms and thus we get nine times more water by transporting
hydrogen only, it shouldn't be hard to decide.

You might want to read the book "The New Solar System" by J.K.Beatty &
A.Chaikin (Ed.) 3rd edition. It has a lot of interesting stuff among
beautiful pictures.

Teemu Makinen / Finnish Meteorological Institute
[e-mail]

Private activities in the net.

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

Date: Thu, 18 Mar 93 07:41:50 GMT
From: Dean Adams <[e-mail]>
Subject: Launch Windows
Newsgroups: sci.space

Does anyone have the current launch window data
for the two upcoming DoD ELV flights?

Last I heard, the Delta II/GPS launch was
scheduled for Thursday at 8pm (PT)...

The Atlas/UFO mission was just rescheduled for March 25th (what time?)
in order to avoid a range conflict with the Shuttle.

What is the exact window times for these missions?

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

From: Pat <[e-mail]>
Subject: NASA Paperwork
Newsgroups: sci.space

Date: 18 Mar 1993 00:32:27 -0500
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In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] ("F.Baube[tm]") writes:
>
>While *some* record-keeping is necessary, well-run projects need much
>less of it.  The SR-71's paperwork lets Lockheed trace every part to
>the piece of titanium it was made from... and there is *still* far
>less paperwork for the Blackbirds than for a typical USAF fighter.



I think people make a mistake of confusing Process control and materials
tracking information from Design Documentation and testing acceptance
and operations manuals and management control tools.  These are a few
different areas.

Process tracking is vital for working back production errors.
Silicon factories, track everything  back to the wafer transporter trays
so to facilitate problem tracking.   This is usually a highly
automated process.

Acceptance testing criteria, is the bench mark for final release.  depending
on the point in process, the test criteria can be fantasy or valid rigorous
review of product.

Operations manuals are necessary for anything more complex then my hedge trimmers.

Management tools are for the brass to figure out  schedule and
budget.

The problem is that the bureaucrats will often fixate on the
design documentation rather then the design.

pat

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

Date: 18 Mar 93 00:50:54 GMT
From: Nick Szabo <[e-mail]>
Subject: plans, and absence thereof
Newsgroups: sci.space,talk.politics.space

[e-mail] (Doug Mohney) writes:
>I wasn't aware that your one penny of every dollar of tax money was
> bigger than the one penny of every tax dollar Mr. Wingo pays.

This is a truly stupid comment.  Wingo gets 100% of his paycheck
from the IRS and pays back 20-30%.  BFD.



--
Nick Szabo                     [e-mail]

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

Date: 18 Mar 1993 05:57:40 GMT
From: "Michael F. Santangelo" <[e-mail]>
Subject: What do we do now with Freedom.
Newsgroups: sci.space

[e-mail] (Pat) writes:


>Okay.  Now that i have thoroughly abused the SSF people let's
>get productive.  What changes in politics/management should be done
>if we want to deliver a working station at some reasonable cost
>and reliability.   Here's my punchlist,  now you NASA folks
>get to take pot shots at me :-)

>1)  Compress the management structure.  keep reston, but fire all but
>30 people.   Everyone at reston should be a top technical specialist
>just keeping tabs on cost, budgets and capabilities.  Fewer managers, less
>paper,  less confusion.

I would hazard to guess Pat that the entire support infrastructure (we
had it explained somewhat acronyms galore a few days ago by one
poster) is based on the current staffing requirement with very little
leeway.  The idea is fine in principle but without throwing the entire
process away and re-inventing it VERY differently from scratch I
doubt seriously this is attainable.

>2) COmpress the centers.  Either Johnson or MSFC should take lead
>on Building and Fabbing the whole thing.  Have 1 contractor as prime.
>Have 1 NASA guy,  who gets shot if the thing don't fly.   And put
>1 NASA guy in charge of each major system.  He gets a budget and a
>performance spec.  If he can't meet it,  he gets cement overshoes.
>If he meets it,  he gets the Medal of Honor.

See note#1 above.

>3) Use Russian Heavy launch gear.  The energiya could sling large
>prefab structures up, and also relax the tightness of mass budgets.

Idea worth exploring, but I think a tough sell politically still, even despite
Clinton's new willingness to help out Boris in his time of (latest) need.
I think engineering changes to support this would be non-trivial and
would actually making it work would probably require a complete overhaul
of the current SSF support infrastructure as I said above.  The current
SSF "organism" would have to be purged from NASA and a completely new
one aspiring to most of the design goals of DCX would need to happen
before you see this.  #3 would have to be a goal (or a major option
to be explored by open minded people) of said new SSF approach.

>4)  GO to 51 degree incline orbits.  Take the hit on shuttle payloads,
>but now get more service capacity from Russian centers.

See above.

>5)  Look at ET wet facilities for additional space.  Dennis doesn't
>like it,  but the ET's provide lots of volume cheap.  some mods and
>they could be easily clipped onto the truss.

>6)  Building ground spares,  both for methodology developement and
>in case you need to cannibalize.

Ha!  Unless SSF funding is but a small fraction of what it has been will
you see Congressional micromanagement allow this.

>7)  More standardization.  Sure  the SSF lab Modules are Spacehab
>compatible and all sorts of great stuff, but what's so bad about
>23" equipment racks?

Not as much big money going to contractors for one.  This is
unfortunately a factor.

>8)  engineering developement flights, to improve knowledge base.
>Take some of the key risk areas,  build some sort of testbed, and
>sling it up on a T4 or Proton and let all that gear run for a few years
>in vacuum.  Instrument it like crazy and see if some of those large
>brush contactors, work in vacuum.

>pat

Seems cynical, but I do beleive that pretty much the entire SSF "organism"
as I call it would need to be purged from NASA before you will get any
of these ideas serious consideration.  It seems these days that in order
to get anything done without costing 10s of billions of dollars you need
the "DCX approach"... keeping it small so it doesn't attract unwanted
attention.  I am not sure however that using completely-off-the-shell
components in something as ambitious as a Space Station is a wise
idea however, otherwise we'll end up with a tin-can-in-orbit.  Somehow
this seems very unglorious and not worth the money and its been done.

Personally I favor a modular approach that starts small but can be
added on to in a way that allows significant future growth.

Problem is, how do you justify throwing away all that money spent
over the last 10 or so years?  So much has been done already on
a very specific design for our Space Station.  Doing something else
in light of this is very hard to swallow.

--
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Michael F. Santangelo                 + Internet: [e-mail]      [work]
Dept. Head-Computer & Network Systems +           [e-mail] [home]
UMCEES / CBL (Solomons Island)        + BITNET:   MIKE@UMUC  [fwd to mike@cbl]

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

Date: 17 Mar 93  21:20:18
From: [e-mail]
Subject: Winding Trails from Rocket Launches
Newsgroups: sci.space

boyd johnson writes:
> I'm sure many of you in Southern California saw the rocket
>contrail from Vandenberg Air Force Base last night (Tuesday) at
>sunset.  I have never seen one as it is created, but have seen it
>many times some time after it happens.

   I saw it too.

>It always seems to resemble something like what you'd get if you
>took the northern lights (aurora borealis) stretched them out, then
>let it snap into a tangled mess.  The trail is nearly vertical near
>the earth, but as it ascends it appears to go out of control.

>Is it the wind currents that twists the contrail or does the rocket
>follow a looping, circling route?  Also, it is always the same time
>of day.  Is this the only time the contrails are visible from a
>distance, or is it when the best atmospheric conditions exist for
>launch? I am about 250 miles from VAFB, so I assume it is visible
>from beyond the Mexican border to San Francisco or so.

    It's wind currents in the upper atmosphere.
    The reason it's the same time each day you see this is from
several reasons -- first, lighting conditions for seeing the rocket
'contrail' is optimal at/near sunset.  Essentially, the plume cloud
is still in sunlight, while the ground is darkened -- making the
plume stand out against a darkening sky.  If the rocket was launched
at night, or during the day, or in at/near sunrise from VAFB, you
could not see the plume standing out and probably would not notice
it.
   As for why does VAFB launch at/near sundown, that is due to
lighting conditions, both at the launch site and destination.
Someone else posted that launching into a specific sunsynchronous
orbit would put the launch window near dawn if it was desired to put
into a 'terminator' (border day/night) orbit.  Yes, that's true, but
very few satellites want that orbit.  Offhand, the only ones I know
of that want that have been a few astronomical satellite (IRAS) and
the set of DMSP (Defense Meteorological Satellite Program)
satellites which gather dawn weather data.  (About 1 launch every 3-5
years, if recollection serves).  There are other weather sunsynch
satellites (including other DMSP satellites ) and other sunsynch
satellites which desire later orbits.  For example, the other DMSP
orbital plane is for a later (2:30 PM?) sunsynch time, and most
earth resources/observations satellites want about 9:30 AM -- not
dawn.
   However, most launches from VAFB are not orbital launches, but
operational test launches for ICBM tests or ICBM R&D.  The timing of
these launches is dictated by lighting conditions at VAFB and at the
target site at Kwajilen Atoll in the Marianas Islands in the South
Pacific.  This sets the lighting conditions normally to just after
dawn at VAFB (I've been to several ICBM launches just after dawn
there), or just at sunset to get the right lighting conditions at
Kwaj, depending on the test desired.  Tests just after dawn normally
don't get noticed, as the plume is not as visible.
  BTW, the plume has been reported from as far east as Las Vegas,
and as far north as Monterey, and as far south as the end of Baja
(for an sunsynch launch).

>Do those of you near Cape Canaveral or other places see similar
>sights?

    They see the plumes, but not the impressive back-lighted post-
sunset sky show.  For example, the post-Challenger plume was visible
for quite a while after launch, and other launches in clear weather
have had plumes visible for up to several hours (although by then
the plume was very tangled and dispersed by upper atmosphere winds
and looked a lot like thin cirrus clouds).  You could get the same
conditions at KSC by launching about a hour or two before sunrise,
but those type of launches don't happen that often there (Shuttle
launches for example, want to launch in full daylight in case they
need to return to the KSC runway in a RTLS emergency).  And there
are a lot more people awake and looking around outside just after
sunset than at just before dawn.
 ----------------------------------------------------------------
 Wales Larrison                         Space Technology Investor


--- Maximus 2.01wb

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

Date: 18 Mar 93 00:47:57 GMT
From: Nick Szabo <[e-mail]>
Subject: Without a Plan
Newsgroups: sci.space,talk.politics.space

[e-mail] (Doug Mohney) writes:

>[Comparing me to Dennis Wingo]
>You've just got your hand out for money for a lot of politically unrealistic
>projects.


This is truly backwards.  Dennis Wingo is a bureaucrat working for
NASA, and constantly posting with his hand out, begging money for
obsolete projects costing $100's of billions.  I volunteer part
of my time designing space projects that _pay for themselves_ by
meeting people's needs in the market, while full time working in the
private sector, producing things people want and need rather than what
politicians think they want and need.  All I ask is that NASA
use its budget more wisely, and devote more of it to projects that
are important to self-sufficient space development, and be far more
open-minded about the wide range of future possibilities for such
development, instead of isolating itself in its own little world of
pork & glory (aka "vision", aka "The Space Program") and demanding
that everybody else to goose-step to their drum.


--
Nick Szabo                     [e-mail]

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End of Space Digest Volume 16 : Issue 334
------------------------------