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Date: Thu, 1 Oct 92 05:27:33
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V15 #270
To: Space Digest Readers
Precedence: bulk
Space Digest Thu, 1 Oct 92 Volume 15 : Issue 270
Today's Topics:
Diffs to sci.space/sci.astro Frequently Asked Questions
Mariner Mark II vs smaller missions
Space FAQ 01/15 - Introduction
Space FAQ 06/15 - Constants and Equations
Space FAQ 07/15 - Astronomical Mnemonics
Space FAQ 08/15 - Addresses
Space FAQ 15/15 - Orbital and Planetary Launch Services
Welcome to the Space Digest!! Please send your messages to
"space@isu.isunet.edu", and (un)subscription requests of the form
"Subscribe Space <your name>" to one of these addresses: listserv@uga
(BITNET), rice::boyle (SPAN/NSInet), utadnx::utspan::rice::boyle
(THENET), or space-REQUEST@isu.isunet.edu (Internet).
----------------------------------------------------------------------
Date: 30 Sep 92 23:04:09 GMT
From: Jon Leech <leech@mahler.cs.unc.edu>
Subject: Diffs to sci.space/sci.astro Frequently Asked Questions
Newsgroups: sci.space,sci.astro,news.answers
Archive-name: space/diff
DIFFS SINCE LAST FAQ POSTING (IN POSTING ORDER)
(These are hand-edited context diffs; do not attempt to use them to patch
old copies of the FAQ).
===================================================================
diff -t -c -r1.12 FAQ.constants
*** /tmp/,RCSt1a23513 Wed Sep 30 19:02:51 1992
--- FAQ.constants Wed Sep 30 18:59:04 1992
***************
*** 48,94 ****
a = 4 pi**2 r / t^2
! For circular Keplerian orbits, where u is gravitational constant, a is
! semimajor axis of orbit, P is period.
! v^2 = u/a
! P = 2pi/(Sqrt(u/a^3))
! u = G * M (can be measured much more accurately than G or M)
!
! Vc = sqrt(M * G / r)
! Vesc = sqrt(2 * M * G / r) = sqrt(2) * Vc
! The period of an eccentric orbit is the same as the period of a
! circular orbit with the same semi-major axis
! 1/2 V**2 - G * M / r = K (conservation of energy)
! where
! Vc = velocity of a circular orbit (you have something like this)
Vesc = escape velocity
K = -G * M / 2 / a
! M = Mass of orbited object
! G = Gravitational constant
r = radius of orbit (measured from center of mass of system)
V = orbital velocity
Change in velocity required for a plane change of angle phi in a
circular orbit:
delta V = 2 sqrt(GM/r) sin (phi/2)
! Energy to put mass m into a circular orbit (ignoring rotational
! velocity of the Earth, which reduces the energy a bit).
GMm (1/Re - 1/2Rcirc)
Re = radius of the earth
Rcirc = radius of the circular orbit.
! Classical rocket equation (dv = change in velocity, ve = exhaust
! velocity, x = reaction mass, m1 = rocket mass excluding reaction
! mass):
!
! dv = Ve * ln((m1 + x) / m1)
! = Ve * ln((final mass) / (initial mass))
! Ve = Isp * g = exhaust velocity, m / s
Isp = specific impulse of engine
! g = 9.80665 m / s^2
Relativistic rocket equation (constant acceleration)
--- 48,97 ----
a = 4 pi**2 r / t^2
! For circular Keplerian orbits where:
! Vc = velocity of a circular orbit
Vesc = escape velocity
K = -G * M / 2 / a
! M = Total mass of orbiting and orbited bodies
! G = Gravitational constant (defined below)
! u = G * M (can be measured much more accurately than G or M)
r = radius of orbit (measured from center of mass of system)
V = orbital velocity
+ P = orbital period
+ a = semimajor axis of orbit
+ Vc = sqrt(M * G / r)
+ Vesc = sqrt(2 * M * G / r) = sqrt(2) * Vc
+ V^2 = u/a
+ P = 2 pi/(Sqrt(u/a^3))
+ K = 1/2 V**2 - G * M / r (conservation of energy)
+
+ The period of an eccentric orbit is the same as the period
+ of a circular orbit with the same semi-major axis.
+
Change in velocity required for a plane change of angle phi in a
circular orbit:
delta V = 2 sqrt(GM/r) sin (phi/2)
! Energy to put mass m into a circular orbit (ignores rotational
! velocity, which reduces the energy a bit).
GMm (1/Re - 1/2Rcirc)
Re = radius of the earth
Rcirc = radius of the circular orbit.
! Classical rocket equation, where
! dv = change in velocity
Isp = specific impulse of engine
! Ve = exhaust velocity
! x = reaction mass
! m1 = rocket mass excluding reaction mass
! g = 9.80665 m / s^2
!
! Ve = Isp * g
! dv = Ve * ln((m1 + x) / m1)
! = Ve * ln((final mass) / (initial mass))
Relativistic rocket equation (constant acceleration)
------------------------------
Date: 30 Sep 92 23:56:50 GMT
From: Anita Cochran <anita@astro.as.utexas.edu>
Subject: Mariner Mark II vs smaller missions
Newsgroups: sci.space
In article <mikew.717692440@kpc.com>, mikew@kpc.com (Mike Wexler) writes:
> anita@astro.as.utexas.edu (Anita Cochran) writes:
>
> It goes with out saying that A single-purpose craft won't be able to
> study the systematics as well as a more expensive multipurpose craft.
> I think the more important question is whether several simple, quick &
> dirty craft are more cost effective than a single expensive craft.
>
> >Well, if we agree that we want to study the system as a whole, this
> >puts certain requirements on the instrument complement. It suggests
> >one needs an imaging instrument, IR and UV spectrometers, and
> >fields and particle experiments. A probe for Titan's atmosphere
> >is a nice thing to have too, once you have a spacecraft going that
> >way. So, add these together and what do you have? You have
> >a Mariner Mark II class mission. And once the spacecraft is going,
> >you might as well send a full spacecraft.
>
> Imagine instead of a Mariner Mark II class mission you have a series of
> missions starting with a relay satellite and following up with separate
> craft with imagine, IR, UV and fields and particle instruments. And with
> the quick turn around you can send updated instruments based on knowledge
> gained by early instruments. You can afford to try more risky techniques
> like ion propulsion and aerobraking.
>
This still does not allow for the systematic studies. Systematic studies
require that you study the various components at the same time. We know
that Saturn is temporally variable -- look at the Saturnian storms
this last year. And it is not sufficient to study part of the problem
without the other problems. If you put the fields and particles experiments
in orbit, you really should have the UV spectrometer since much of
the fields phenomena like aurorae and sub-storms have a UV signature.
And you really would like an image to put the conditions in the atmosphere
in context. So now you are talking UVS, imaging and fields and particles.
That is NOT a small mission any more. Now, you say we will study the
surfaces so we would like to do some spectral work so we send VIMS
(visual and Infrared Mapping Spectrometer) and maybe cover the thermal
IR. But we would like to have things in context and want to study
the geomorphology so you have to send
a camera. This is also NOT a small mission. Now you want to study the
atmosphere. Well, you need the UV spectrometer and probably CIRS (Cassini
IR spectrometer) and, guess what, you need imaging to put things in context
and to study the dynamics. None of these are small missions.
And by the time you have now sent 3 moderate missions and they should
all go at the same time (see the temporal issue above) you are back to
a big mission so let's fly Cassini.
Now, if you don't want systematics, the smaller missions are fine but if
you concede that you want to study the systematics, you have
to have a big mission.
And new technology does not only mean ion drives and solar sails. The
CIRS is THE MOST SOPHISTICATED IR spectrometer we have yet built for
space. Its PI expressed the opinion last week at a Goddard meeting that
it probably is the most sophisticated which will ever fly since you cannot
do it smaller (this has nothing to do with detectors or electronics but
the need for big optics). And the Ion Mass Spectrometers are getting
more and more sophisticated. And the CCDs which were developed for
CRAF and Cassini opened up a whole new world in CCDs and resulted in
the new WF/PC II cameras on HST. So you see, these missions are cutting
edge in their own way. Yes, they are expensive. And there is where
you must make the decision of what are your priorities and what kinds
of questions you want to answer. There is no absolute path but
Cassini is NOT old-fashioned technology.
--
Anita Cochran uucp: !utastro!anita
arpa: anita@astro.as.utexas.edu
snail: Astronomy Dept., The Univ. of Texas, Austin, TX, 78712
at&t: (512) 471-1471
------------------------------
Date: 30 Sep 92 23:05:42 GMT
From: Jon Leech <leech@mahler.cs.unc.edu>
Subject: Space FAQ 01/15 - Introduction
Newsgroups: sci.astro,sci.space,news.answers
Archive-name: space/intro
Last-modified: $Date: 92/09/30 18:59:11 $
FREQUENTLY ASKED QUESTIONS ON SCI.SPACE/SCI.ASTRO
INTRODUCTION
This series of linked messages is periodically posted to the Usenet
groups sci.space and sci.astro in an attempt to provide good answers to
frequently asked questions and other reference material which is worth
preserving. If you have corrections or answers to other frequently asked
questions that you would like included in this posting, send email to
leech@cs.unc.edu (Jon Leech).
If you don't want to see the FAQ, add 'Frequently Asked Questions' to
your KILL file for this group (if you're not reading this with a newsreader
that can kill articles by subject, you're out of luck).
The FAQ volume is excessive right now and will hopefully be trimmed down
by rewriting and condensing over time. The FAQ postings are available in
the Ames SPACE archive in FAQ/faq<#>.
Good summaries will be accepted in place of the answers given here. The
point of this is to circulate existing information, and avoid rehashing old
answers. Better to build on top than start again. Nothing more depressing
than rehashing old topics for the 100th time. References are provided
because they give more complete information than any short generalization.
Questions fall into three basic types:
1) Where do I find some information about space?
Try your local public library first. The net is not a good place to ask
for general information. Ask INDIVIDUALS (by email) if you must. There
are other sources, use them, too. The net is a place for open ended
discussion.
2) I have an idea which would improve space flight?
Hope you aren't surprised, but 9,999 out of 10,000 have usually been
thought of before. Again, contact a direct individual source for
evaluation. NASA fields thousands of these each day.
3) Miscellanous queries.
These are addressed on a case-by-case basis in the following series of
FAQ postings.
SUGGESTIONS FOR BETTER NETIQUETTE
Read news.announce.newusers if you're on Usenet.
Minimize cross references, [Do you REALLY NEED to?]
Edit "Subject:" lines, especially if you're taking a tangent.
Send mail instead, avoid posting follow ups. (1 mail message worth
100 posts).
Internet mail readers: send requests to add/drop to SPACE-REQUEST
not SPACE.
Read all available articles before posting a follow-up. (Check all
references.)
Cut down attributed articles (leave only the points you're
responding to; remove signatures and headers). Summarize!
Put a return address in the body (signature) of your message (mail
or article), state your institution, etc. Don't assume the
'reply' function of mailers will work.
Use absolute dates. Post in a timely way. Don't post what everyone
will get on TV anyway.
Some editors and window systems do character count line wrapping:
keep lines under 80 characters for those using ASCII terminals
(use carriage returns).
INDEX TO LINKED POSTINGS
I've attempted to break the postings up into related areas. There isn't
a keyword index yet; the following lists the major subject areas in each
posting. Only those containing astronomy-related material are posted to
sci.astro (indicated by '*' following the posting number).
# Contents
1* Introduction
Suggestions for better netiquette
Index to linked postings
Notes on addresses, phone numbers, etc.
Contributors
2* Network resources
Overview
Mailing lists
Periodically updated information
Warning about non-public networks
3* Online (and some offline) sources of images, data, etc.
Introduction
Viewing Images
Online Archives
NASA Ames
NASA Spacelink
National Space Science Data Center
Space And Planetary Image Facility
Space Telescope Science Institute Electronic Info. Service
Astronomical Databases
Astronomy Programs
Orbital Element Sets
SPACE Digest
Landsat & NASA Photos
Planetary Maps
Cometary Orbits
4* Performing calculations and interpreting data formats
Computing spacecraft orbits and trajectories
Computing planetary positions
Computing crater diameters from Earth-impacting asteroids
Map projections and spherical trignometry
Performing N-body simulations efficiently
Interpreting the FITS image format
Sky (Unix ephemeris program)
Three-dimensional star/galaxy coordinates
5* References on specific areas
Publishers of space/astronomy material
Careers in the space industry
DC-X single-stage to orbit (SSTO) program
LLNL "great exploration"
Lunar science and activities
Spacecraft models
Rocket propulsion
Spacecraft design
Esoteric propulsion schemes (solar sails, lasers, fusion...)
Spy satellites
Space shuttle computer systems
SETI computation (signal processing)
Amateur satellies & weather satellites
Tides
6* Constants and equations for calculations
7* Astronomical Mnemonics
8 Contacting NASA, ESA, and other space agencies/companies
NASA Centers / Arianespace / ESA / NASDA / Soyuzkarta / Space
Camp / Space Commerce Corporation / Spacehab / SPOT Image
Other commercial space businesses
9 Space shuttle answers, launch schedules, TV coverage
Shuttle launchings and landings; schedules and how to see them
How to receive the NASA TV channel, NASA SELECT
Dial-A-Shuttle and how to use it
Amateur radio frequencies for shuttle missions
Solid Rocket Booster fuel composition
10 Planetary probes - Historical Missions
US planetary missions
Mariner (Venus, Mars, & Mercury flybys and orbiters)
Pioneer (Moon, Sun, Venus, Jupiter, and Saturn flybys and orbiters)
Ranger (Lunar lander and impact missions)
Lunar Orbiter (Lunar surface photography)
Surveyor (Lunar soft landers)
Viking (Mars orbiters and landers)
Voyager (Outer planet flybys)
Soviet planetary missions
Soviet Lunar probes
Soviet Venus probes
Soviet Mars probes
Japanese planetary missions
Planetary mission references
11 Upcoming planetary probes - missions and schedules
Galileo
Mars Observer
CRAF
Cassini
Other space science missions
12 Controversial questions
What happened to the Saturn V plans
Why data from space missions isn't immediately available
Risks of nuclear (RTG) power sources for space probes
Impact of the space shuttle on the ozone layer
How long can a human live unprotected in space
Using the shuttle beyond Low Earth Orbit
The "Face on Mars"
13 Space activist/interest/research groups and space publications
Groups
Publications
Undocumented Groups
14 How to become an astronaut
15 Orbital and Planetary Launch Services
NOTES ON ADDRESSES, PHONE NUMBERS, ETC.
Unless otherwise specified, telephone numbers, addresses, and so on are
for the United States of America. Non-US readers should remember to add
the country code for telephone calls, etc.
CREDITS
Eugene Miya started a series of linked FAQ postings some years ago which
inspired (and was largely absorbed into) this set.
Peter Yee and Ron Baalke have and continue to spend a lot of their own
time setting up the SPACE archives at NASA Ames and forwarding official
NASA announcements.
Many other people have contributed material to this list in the form of
old postings to sci.space and sci.astro which I've edited. Please let me
know if corrections need to be made. Contributors I've managed to keep
track of are:
0004847546@mcimail.com (Francis Reddy) - map projections
akerman@bill.phy.queensu.CA (Richard Akerman) - crater diameters
alweigel@athena.mit.edu (Lisa Weigel) - SEDS info
aoab314@emx.utexas.edu (Srinivas Bettadpur) - tides
awpaeth@watcgl.waterloo.edu (Alan Wm Paeth) - map projections
aws@iti.org (Allen W. Sherzer) - Great Exploration
baalke@kelvin.jpl.nasa.gov (Ron Baalke) - planetary probe schedules
bankst@rata.vuw.ac.nz (Timothy Banks) - map projections,
variable star analysis archive
brosen@pioneer.arc.nasa.gov (Bernie Rosen) - Space Camp
bschlesinger@nssdca.gsfc.nasa.gov (Barry Schlesinger) - FITS format
cew@venera.isi.edu (Craig E. Ward) - space group contact info
chapin@cbnewsc.att.com (Tom Chapin) - planetary positions
cunnida@tenet.edu (D. Alan Cunningham) - NASA Spacelink
cyamamot@kilroy.Jpl.Nasa.Gov (Cliff Yamamoto) - orbital elements
datri@convex.com (Anthony Datri) - PDS/VICAR viewing software
daver@sjc.mentorg.com (Dave Rickel) - orbit formulae
dlbres10@pc.usl.edu (Phil Fraering) - propulsion
eder@hsvaic.boeing.com (Dani Eder) - Saturn V plans, SRBs
eugene@eos.arc.nasa.gov (Eugene N. Miya) - introduction,
NASA contact info, started FAQ postings
g@telesoft.com (Gary Morris) - amateur radio info
gaetz@uwovax.uwo.ca (Terry Gaetz) - N-body calculations,
orbital dynamics
grandi@noao.edu (Steve Grandi) - planetary positions
greer%utd201.dnet%utadnx@utspan.span.nasa.gov (Dale M. Greer) - constants
henry@zoo.toronto.edu (Henry Spencer) - survival in vacuum,
astronaut how-to, publication refs, DC-X
higgins@fnal.bitnet (William Higgins) - RTGs, publishers,
shuttle landings, spysats, propulsion, "Face on Mars"
hmueller@cssun.tamu.edu (Hal Mueller) - map projections,
orbital dynamics
jim@pnet01.cts.com (Jim Bowery) - propulsion, launch services
jscotti@lpl.arizona.edu (Jim Scotti) - planetary positions
kcarroll@zoo.toronto.edu (Kieran A. Carroll)- refs for spacecraft design
ken@orion.bitnet (Kenneth Ng) - RTGs
klaes@verga.enet.dec.com (Larry Klaes) - planetary probe history
leech@cs.unc.edu (Jon Leech) - crater diameters
lfa@vielle.cray.com (Lou Adornato) - orbital dynamics
maury.markowitz@egsgate.fidonet.org (Maury Markowitz) - propulsion
mbellon@mcdurb.Urbana.Gould.COM - N-body calculations
mcconley@phoenix.Princeton.edu (Marc Wayne Mcconley) - space careers
msb@sq.com (Mark Brader) - Mariner 1 info.
mwm@cmu.edu (Mark Maimone) - SPACE Digest
nickw@syma.sussex.ac.uk (Dr. Nick Watkins) - models, spysats
opus@pioneer.unm.edu (Colby Kraybill) - SPIF data archive
panama@cup.portal.com (Kenneth W Durham) - cometary orbits, IAU
paul.blase@nss.fidonet.org (Paul Blase) - propulsion
pjs@plato.jpl.nasa.gov (Peter Scott) - RTGs
pschleck@unomaha.edu (Paul W. Schleck) - AMSAT, ARRL contact info
rdb@mel.cocam.oz.au (Rodney Brown) - propulsion refs
rja7m@phil.cs.virginia.edu (Ran Atkinson) - FTPable astro. programs
rjungcla@ihlpb.att.com (R. Michael Jungclas)- models
seal@leonardo.jpl.nasa.gov (David Seal) - Cassini mission schedule
shafer@skipper.dfrf.nasa.gov (Mary Shafer) - photos, shuttle landings
smith@sndpit.enet.dec.com (Willie Smith) - photos
stephen@gpwd.gp.co.nz (Stephen Dixon) - shuttle audio frequencies
sterner@warper.jhuapl.edu (Ray Sterner) - planetary positions
stooke@vaxr.sscl.uwo.ca (Phil Stooke) - planetary maps
ted_anderson@transarc.com (Ted Anderson) - propulsion
terry@astro.as.utexas.edu (Terry Hancock) - NASA center info
thorson@typhoon.atmos.coloState.edu (Bill Thorson) - FITS info
tm2b+@andrew.cmu.edu (Todd L. Masco) - SPACE Digest
tom@ssd.csd.harris.com (Tom Horsley) - refs for algorithms
veikko.makela@helsinki.fi (Veikko Makela) - orbital element sets
wayne@csri.utoronto.ca (Wayne Hayes) - constants
weemba@libra.wistar.upenn.edu (Matthew P Wiener) - Voyager history
yamada@yscvax.ysc.go.jp (Yoshiro Yamada) - ISAS/NASDA missions
yee@ames.arc.nasa.gov (Peter Yee) - AMES archive server,
propulsion
In Net memoriam:
Ted Flinn
NEXT: FAQ #2/15 - Network Resources
------------------------------
Date: 30 Sep 92 23:07:01 GMT
From: Jon Leech <leech@mahler.cs.unc.edu>
Subject: Space FAQ 06/15 - Constants and Equations
Newsgroups: sci.astro,sci.space,news.answers
Archive-name: space/constants
Last-modified: $Date: 92/09/30 18:59:02 $
CONSTANTS AND EQUATIONS FOR CALCULATIONS
This list was originally compiled by Dale Greer. Additions would be
appreciated.
Numbers in parentheses are approximations that will serve for most
blue-skying purposes.
Unix systems provide the 'units' program, useful in converting
between different systems (metric/English, etc.)
NUMBERS
7726 m/s (8000) -- Earth orbital velocity at 300 km altitude
3075 m/s (3000) -- Earth orbital velocity at 35786 km (geosync)
6378 km (6400) -- Mean radius of Earth
1738 km (1700) -- Mean radius of Moon
5.974e24 kg (6e24) -- Mass of Earth
7.348e22 kg (7e22) -- Mass of Moon
1.989e30 kg (2e30) -- Mass of Sun
3.986e14 m^3/s^2 (4e14) -- Gravitational constant times mass of Earth
4.903e12 m^3/s^2 (5e12) -- Gravitational constant times mass of Moon
1.327e20 m^3/s^2 (13e19) -- Gravitational constant times mass of Sun
384401 km ( 4e5) -- Mean Earth-Moon distance
1.496e11 m (15e10) -- Mean Earth-Sun distance (Astronomical Unit)
1 megaton (MT) TNT = about 4.2e15 J or the energy equivalent of
about .05 kg (50 gm) of matter. Ref: J.R Williams, "The Energy Level
of Things", Air Force Special Weapons Center (ARDC), Kirtland Air
Force Base, New Mexico, 1963. Also see "The Effects of Nuclear
Weapons", compiled by S. Glasstone and P.J. Dolan, published by the
US Department of Defense (obtain from the GPO).
EQUATIONS
Where d is distance, v is velocity, a is acceleration, t is time.
For constant acceleration
d = d0 + vt + .5at^2
v = v0 + at
v^2 = 2ad
Acceleration on a cylinder (space colony, etc.) of radius r and
rotation period t:
a = 4 pi**2 r / t^2
For circular Keplerian orbits where:
Vc = velocity of a circular orbit
Vesc = escape velocity
K = -G * M / 2 / a
M = Total mass of orbiting and orbited bodies
G = Gravitational constant (defined below)
u = G * M (can be measured much more accurately than G or M)
r = radius of orbit (measured from center of mass of system)
V = orbital velocity
P = orbital period
a = semimajor axis of orbit
Vc = sqrt(M * G / r)
Vesc = sqrt(2 * M * G / r) = sqrt(2) * Vc
V^2 = u/a
P = 2 pi/(Sqrt(u/a^3))
K = 1/2 V**2 - G * M / r (conservation of energy)
The period of an eccentric orbit is the same as the period
of a circular orbit with the same semi-major axis.
Change in velocity required for a plane change of angle phi in a
circular orbit:
delta V = 2 sqrt(GM/r) sin (phi/2)
Energy to put mass m into a circular orbit (ignores rotational
velocity, which reduces the energy a bit).
GMm (1/Re - 1/2Rcirc)
Re = radius of the earth
Rcirc = radius of the circular orbit.
Classical rocket equation, where
dv = change in velocity
Isp = specific impulse of engine
Ve = exhaust velocity
x = reaction mass
m1 = rocket mass excluding reaction mass
g = 9.80665 m / s^2
Ve = Isp * g
dv = Ve * ln((m1 + x) / m1)
= Ve * ln((final mass) / (initial mass))
Relativistic rocket equation (constant acceleration)
t (unaccelerated) = c/a * sinh(a*t/c)
d = c**2/a * (cosh(a*t/c) - 1)
v = c * tanh(a*t/c)
Relativistic rocket with exhaust velocity Ve and mass ratio MR:
at/c = Ve/c * ln(MR), or
t (unaccelerated) = c/a * sinh(Ve/c * ln(MR))
d = c**2/a * (cosh(Ve/C * ln(MR)) - 1)
v = c * tanh(Ve/C * ln(MR))
Converting from parallax to distance:
d (in parsecs) = 1 / p (in arc seconds)
d (in astronomical units) = 206265 / p
Miscellaneous
f=ma -- Force is mass times acceleration
w=fd -- Work (energy) is force times distance
Atmospheric density varies as exp(-mgz/kT) where z is altitude, m is
molecular weight in kg of air, g is local acceleration of gravity, T
is temperature, k is Bolztmann's constant. On Earth up to 100 km,
d = d0*exp(-z*1.42e-4)
where d is density, d0 is density at 0km, is approximately true, so
d@12km (40000 ft) = d0*.18
d@9 km (30000 ft) = d0*.27
d@6 km (20000 ft) = d0*.43
d@3 km (10000 ft) = d0*.65
Titius-Bode Law for approximating planetary distances:
R(n) = 0.4 + 0.3 * 2^N Astronomical Units (N = -infinity for
Mercury, 0 for Venus, 1 for Earth, etc.)
This fits fairly well except for Neptune.
CONSTANTS
6.62618e-34 J-s (7e-34) -- Planck's Constant "h"
1.054589e-34 J-s (1e-34) -- Planck's Constant / (2 * PI), "h bar"
1.3807e-23 J/K (1.4e-23) - Boltzmann's Constant "k"
5.6697e-8 W/m^2/K (6e-8) -- Stephan-Boltzmann Constant "sigma"
6.673e-11 N m^2/kg^2 (7e-11) -- Newton's Gravitational Constant "G"
0.0029 m K (3e-3) -- Wien's Constant "sigma(W)"
3.827e26 W (4e26) -- Luminosity of Sun
1370 W / m^2 (1400) -- Solar Constant (intensity at 1 AU)
6.96e8 m (7e8) -- radius of Sun
1738 km (2e3) -- radius of Moon
299792458 m/s (3e8) -- speed of light in vacuum "c"
9.46053e15 m (1e16) -- light year
206264.806 AU (2e5) -- \
3.2616 light years (3) -- --> parsec
3.0856e16 m (3e16) -- /
Black Hole radius (also called Schwarzschild Radius):
2GM/c^2, where G is Newton's Grav Constant, M is mass of BH,
c is speed of light
Things to add (somebody look them up!)
Basic rocketry numbers & equations
Aerodynamical stuff
Energy to put a pound into orbit or accelerate to interstellar
velocities.
Non-circular cases?
Atmosphere scale height for various planets.
NEXT: FAQ #7/15 - Astronomical Mnemonics
------------------------------
Date: 30 Sep 92 23:07:06 GMT
From: Jon Leech <leech@mahler.cs.unc.edu>
Subject: Space FAQ 07/15 - Astronomical Mnemonics
Newsgroups: sci.astro,sci.space,news.answers
Archive-name: space/mnemonics
Last-modified: $Date: 92/09/30 18:59:18 $
ASTRONOMICAL MNEMONICS (This is the last FAQ section posted to sci.astro)
Gathered from various flurries of mnemonic postings on sci.astro.
Spectral classification sequence: O B A F G K M R N S
Oh Be A Fine Girl Kiss Me Right Now, Sweetheart. (a classic)
O'Dell's Big Astronomical Fiasco Gonna Kill Me Right Now Surely
Obese Balding Astronomy Found Guilty; Killed Many Reluctant
Nonscience Students.
Octopus Brains, A Favorite Gastronomical Kitchen Menu,
Requires No Sauce
Odd Ball Astronomers Find Generally Kooky Mnemonics
Really Nifty Stuff
Oh Big And Ferocious Gorilla, Kill My Roomate Next Saturday
Oh Boy, A Flash! Godzilla Kills Mothra! Really Not Surprising!
Oh Boy, An F Grade Kills Me
On Bad Afternoons Fermented Grapes Keep Mrs. Richard Nixon Smiling
On, Backward Astronomer, Forget Geocentricity; Kepler's Motions
Reveal Nature's Simplicity
Our Bad Astronomy Faculty Gets Killed Monday
Oven Baked Ants, Fried Gently, Kept Moist, Retain Natural Succulence
Overseas Broadcast: A Flash! Godzilla kills Mothra!
(Rodan Named Successor)
Overweight Boys and Fat Girls Keep Munching
Only Bored Astronomers Find Gratification Knowing Mnemonics
Oh Bloody Astronomy! F Grades Kill Me
Order of the planets:
Sun
Mercury
Venus
Earth (Terra)
Mars
(Asteroids)
Jupiter
Saturn
Uranus
Neptune
Pluto
My Very Earnest Mother Just Served Us Nine Pizzas
Mother Very Thoughtfully Made A Jelly Sandwich Under No Protest
My Very Erotic Mate Joyfully Satisfies Unusual Needs Passionately
Men Very Easily Make Jugs Serve Useful Nocturnal Purposes
Man Very Early Made A Jug Serve Useful Noble Purposes
My Very Educated Mother Just Showed Us Nine Planets
My Very Eager Mother Just Showed Us Nine Planets
My Very Exhausted Mother hAs Just Swept Up a Planetary Nebula
Most Voters Earn Money Just Showing Up Near Polls
My Very Educated Mother Just Served Us Nine Pizza-pies
Many Viscious Elephants Made John, Suzy and Uncle Need Protection
Solar Mass Very Easily Makes All Jupiter's Satellites Undergo
Numerous Perturbations.
Mein Vater erklaert mir jeden Sonntag unseren niedlichen Planeten
Colors of the spectrum: Red Orange Yellow Green Blue Indigo Violet
ROY G. BIV (pronounce as a man's name)
Richard Of York Gave Battle In Vain
Read Out Your Good Book In Verse
Galilean Satellite of Jupiter: Io Europa Ganymede Callisto
I Expect God Cries
I Eat Green Cheese
Ich Erschrecke alle Guten Christen
Saturnian Satellites
MET DR THIP
Miriam's Enchiladas Taste Divine Recently. Tell Her I'm Proud.
(Mimas, Enceladus, Tethys, Dione, Rhea, Titan, Hyperion,
Iapetus, Phoebe)
Uranian Satellites:
MAUTO
Mispronunciations Afflict Uranus Too Often
My Angel Uriel Takes Opium
(Miranda, Ariel, Umbriel, Titania, Oberon)
NOTE: the remaining FAQ sections do not appear in sci.astro, as they cover
material of relevance only to sci.space.
NEXT: FAQ #8/15 - Contacting NASA, ESA, and other space agencies/companies
------------------------------
Date: 30 Sep 92 23:07:10 GMT
From: Jon Leech <leech@mahler.cs.unc.edu>
Subject: Space FAQ 08/15 - Addresses
Newsgroups: sci.space,news.answers
Archive-name: space/addresses
Last-modified: $Date: 92/09/30 18:58:49 $
CONTACTING NASA, ESA, AND OTHER SPACE AGENCIES/COMPANIES
Many space activities center around large Government or International
Bureaucracies. In the US that means NASA. If you have basic information
requests: (e.g., general PR info, research grants, data, limited tours, and
ESPECIALLY SUMMER EMPLOYMENT (typically resumes should be ready by Jan. 1),
etc.), consider contacting the nearest NASA Center to answer your questions.
EMail typically will not get you any where, computers are used by
investigators, not PR people. The typical volume of mail per Center is a
multiple of 10,000 letters a day. Seek the Public Information Office at one
of the below, this is their job:
NASA (The National Aeronautics and Space Administration) is the
civilian space agency of of the United States Federal Government.
It reports directly to the White House and is not a Cabinet
post such as the military Department of Defense. Its 20K+ employees
are civil servants and hence US citizens. Another 100K+ contractors
also work for NASA.
NASA CENTERS
NASA Headquarters (NASA HQ)
Washington DC 20546
Ask them questions about policy, money, and things of political
nature. Direct specific questions to the appropriate center.
NASA Ames Research Center (ARC)
Moffett Field, CA 94035
Some aeronautical research, atmosphere reentry, Mars and Venus
planetary atmospheres. "Lead center" for Helicopter research,
V/STOL, etc. Runs Pioneer series of space probes.
NASA Ames Research Center
Dryden Flight Research Facility [DFRF]
P. O. Box 273
Edwards, CA 93523
Aircraft, mostly. Tested the shuttle orbiter landing
characteristics. Developed X-1, D-558, X-3, X-4, X-5, XB-70, and of
course, the X-15.
NASA Goddard Space Flight Center (GSFC)
Greenbelt, MD 20771
[Outside of Washington DC]
Earth orbiting unmanned satellites and sounding rockets. Developed
LANDSAT.
NASA Lewis Research Center (LeRC)
21000 Brookpark Rd.
Cleveland, OH 44135
Aircraft/Rocket propulsion. Space power generation. Materials
research.
NASA Johnson Manned Space Center (JSC)
Houston, TX 77058
JSC manages Space Shuttle, ground control of manned missions.
Astronaut training. Manned mission simulators.
NASA Kennedy Space Flight Center (KSC)
Titusville, FL 32899
Space launch center. You know this one.
NASA Marshall Space Flight Center (MSFC)
Huntsville, AL 35812
Development, production, delivery of Solid Rocket Boosters, External
Tank, Orbiter main engines. Propulsion and launchers.
NASA Langley Research Center (LaRC)
Hampton, VA 23665
[Near Newport News, VA]
Original NASA site. Specializes in theoretical and experimental
flight dynamics. Viking. Long Duration Exposure Facility.
Wallops Flight Center
Wallops Island, Virginia 23337
Aeronautical research, sounding rockets, Scout launcher.
Jet Propulsion Laboratory [JPL/CIT]
California Institute of Technology
4800 Oak Grove Dr.
Pasadena, CA 91109
The "heavies" in planetary research probes and other unmanned
projects (they also had a lot to do with IRAS). They run Voyager,
Magellan, Galileo, and will run Cassini, CRAF, etc. etc.. For
images, probe navigation, and other info about unmanned exploration,
this is the place to go.
JPL is run under contract for NASA by the nearby California
Institute of Technology, unlike the NASA centers above. This
distinction is subtle but critical. JPL has different requirements
for unsolicited research proposals and summer hires. For instance in
the latter, an SF 171 is useless. Employees are Caltech employees,
contractors, and for the most part have similar responsibilities.
They offer an alternative to funding after other NASA Centers.
Manager, Technology Utilization Office
NASA Scientific and Technical Information Facility
Post Office Box 8757
Baltimore, Maryland 21240
Specific requests for software must go thru COSMIC at the Univ. of
Georgia, NASA's contracted software redistribution service. You can
reach them at cosmic@uga.bitnet.
NOTE: Foreign nationals requesting information must go through their
Embassies in Washington DC. These are facilities of the US Government
and are regarded with some degree of economic sensitivity. Centers
cannot directly return information without high Center approval. Allow
at least 1 month for clearance. This includes COSMIC.
The US Air Force Space Command can be contacted thru the Pentagon along with
other Department of Defense offices. They have unacknowledged offices in
Los Angeles, Sunnyvale, Colorado Springs, and other locations. They have
a budget which rivals NASA in size.
ARIANESPACE HEADQUARTERS
Boulevard de l'Europe
B.P. 177
91006 Evry Cedex
France
ARIANESPACE, INC.
1747 Pennsylvania Avenue, NW Suite 875
Washington, DC 20006
(202)-728-9075
EUROPEAN SPACE AGENCY
955 L'Enfant Plaza S.W.
Washington, D.C. 20024
(202)-488-4158
NATIONAL SPACE DEVELOPMENT AGENCY (NASDA)
4-1 Hamamatsu-Cho, 2 Chome
Minato-Ku, Tokyo 105, JAPAN
SOYUZKARTA
45 Vologradsij Pr.
Moscow 109125
USSR
SPACE CAMP
Alabama Space and Rocket Center U.S. SPACE CAMP
1 Tranquility Base 6225 Vectorspace Blvd
Huntsville, AL 35805 Titusville FL 32780
(205)-837-3400 (407)267-3184
Registration and mailing list are handled through Huntsville -- both
camps are described in the same brochure.
Programs offered at Space Camp are:
Space Camp - one week, youngsters completing grades 4-6
Space Academy I - one week, grades 7-9
Aviation Challenge - one week high school program, grades 9-11
Space Academy II - 8 days, college accredited, grades 10-12
Adult Program - 3 days (editorial comment: it's great!)
Teachers Program - 5 days
SPACE COMMERCE CORPORATION (U.S. agent for Soviet launch services)
504 Pluto Drive 69th flr, Texas Commerce Tower
Colorado Springs, CO 80906 Houston, TX 77002
(719)-578-5490 (713)-227-9000
SPACEHAB
600 Maryland Avenue, SW
Suite 201 West
Washington, DC 20004
(202)-488-3483
SPOT IMAGE CORPORATION
1857 Preston White Drive,
Reston, VA 22091
(FAX) (703)-648-1813 (703)-620-2200
OTHER COMMERCIAL SPACE BUSINESSES
Vincent Cate maintains a list with addresses and some info for a variety
of companies in space-related businesses. This is mailed out on the
space-investors list he runs (see the "Network Resources" FAQ) and is also
available by anonymous ftp from furmint.nectar.cs.cmu.edu (128.2.209.111) in
/usr/vac/ftp/space-companies.
NEXT: FAQ #9/15 - Schedules for space missions, and how to see them
------------------------------
Date: 30 Sep 92 23:07:48 GMT
From: Jon Leech <leech@mahler.cs.unc.edu>
Subject: Space FAQ 15/15 - Orbital and Planetary Launch Services
Newsgroups: sci.space,news.answers
Archive-name: space/launchers
Last-modified: $Date: 92/09/30 18:59:13 $
ORBITAL AND PLANETARY LAUNCH SERVICES
If anyone has more accurate or more complete information, please post
it and copy jim@pnet01.cts.com (Jim Bowery), who maintains the primary
copy of this item. Don't forget to include the source of the
information.
PAYLOAD(LBS) DELIVERED TO
COMPANY/VEHICLE $M LEO GTO GEO ESCAPE U.STAGE LAUNCHFAIL(1)
MM/Titan4[H] 296 47000 .... 10300 .... Centaur .... ....
MM/Titan4 277 49000 15000 5800 .... IUS .... ....
MM/Titan3 160 32500 12474 4100 .... TOS .... ....
AS/Arian44L[H] 110 21164 9259 5500 .... none .... ....
GD/Atlas2 80 15700 6200 3000 .... Centaur .... ....
MD/Delta2 52 11100 4010 2000 2816[S] PAMD[H] .... ....
GW/LongMarch3 45 6614 2866 1433 .... none .... ....
EPAC/EagleS2[E] 30 10000(2)5128 3374 ....(4) USTM(3) 0 0
OSC/Taurus[S] 17 2703 .... .... 374 .... 0 0
EPAC/EagleS1[E] 15 6000 .... .... ....(4) USTM 0 0
AMROC/Aquila[S] 10 2000 1467 .... .... none 0 0
SSI/Conestoga 10 1500(5) 900(6) 550(7) .... 0 0
OSC/Pegasus[H] 9.7 750 .... .... .... none 2 1
EPAC/Eagle[E] 6.7 3000 .... .... .... USTM 0 0
(1) For launches where reflight insurance is issued, the fraction of the
launch cost indemnified is the failure level for that flight.
For launches where reflight insurance is not issued, a rough
estimate is made as to the fraction of the launch cost that
would have been indemnified.
(2) LEO given is 300nmi altitude [S].
(3) The bipropellant (Isp=323) USTM has a dry weight of approximately 1600LBS
which must be subtracted from the total weight to determine weight
available for electronics, power, communication and fuel. The USTM
provides station-keeping and course correction in addition to
transfer and apogee burns.
(4) According to [S] escape requires 170kg MMH/NTO fuel with USTM.
(5) 200nmi altitude 37.9d inclination [S].
(6) 400nmi altitude [S].
(7) Includes Conestoga apogee kick stage weight.
REFLIGHT
VEHICLE POLARLBS(9) INSURANCE(%) ACCURACY PAD WEIGHT
MM/Titan4[H] .... .... .... 1910449
MM/Titan4 .... .... .... 1885525
MM/Titan3 .... .... .... 1492200
AS/Arian44L .... .... .... 1033000
GD/Atlas2 12400 .... .... 360600
MD/Delta2 8401 .... .... 450000
GW/LongMarch3 .... .... .... 444400
EPAC/EagleS2[E] .... 18 1.4km(9) 268145
OSC/Taurus[S] 2140 .... .... ....
EPAC/EagleS1[E] .... 18 1.4km(9) ....
AMROC/Aquila[S] 1467 .... .... ....
SSI/Conestoga 900 .... 9.3km(10) ....
OSC/Pegasus[S] 649 .... .... ....
EPAC/Eagle .... 18 .... 99134
(9) For unknown data, conservative figures for polar orbit can be
estimated by dividing LEO weight by 2.
(10) Circular orbit and <0.02d inclination error to 3 sigma [S].
(11) Reduced payload for upper stage with thrust vector control. 1 sigma [S].
Figures given as "...." are to be included in a future release.
Information sources are indicated by a source code within square brackets.
For example [H] means the associated information and subsequent information
comes from the 1989 Hughes Corp. Survey with dollars given in 1989 dollars.
Source codes: H = 1989 Hughes Corp. Survey
E = 9/1991 E'Prime Aerospace Corp. report
S = "A Status Report on the Availability of Expendable
Launch Vehicles for Small Solar System
Exploration Payloads", Jim McAdams, Science
Applications International Corp. 3/31/1991
------------------------------
End of Space Digest Volume 15 : Issue 270
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