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Date: Sun, 8 Nov 92 05:03:24
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V15 #395
To: Space Digest Readers
Precedence: bulk
Space Digest Sun, 8 Nov 92 Volume 15 : Issue 395
Today's Topics:
HOW TO GET DATA AND IMAGES
Hubble's mirror
Moon can hold its air (was Re: Mars over the Moon???)
Ten embarrassed questions about the moon (very long)
the Happyface on Mars
Viking Photos Shows Evidence of Marsquakes
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: Sat, 07 Nov 92 19:08:17 GMT
From: Craig Fifer <cfifer@rvgs.vak12ed.edu>
Subject: HOW TO GET DATA AND IMAGES
Newsgroups: sci.space
INTRODUCTION
A wide variety of images, data, catalogs, information
releases, and
other material dealing with space and astronomy may be
found on the net.
A few sites offer direct dialup access or remote login
access, while the
remainder support some form of file transfer. Many sites
are listed as
providing 'anonymous FTP'. This refers to the File Transfer
Protocol on
the Internet. Sites not connected to the Internet cannot
use FTP
directly, but there are a few automated FTP servers which
operates via
email. Send mail containing only the word HELP to
ftpmail@decwrl.dec.com
or bitftp@pucc.princeton.edu, and the servers will send you
instructions
on how to make requests.
The sources with the broadest selection of material are the
NASA Ames
SPACE archive and the National Space Science Data Center.
Don't even ask for images to be posted to the net. The data
volume is
huge and nobody wants to spend the time on it.
VIEWING IMAGES
The possible combinations of image formats and machines is
forebodingly
large, and I won't attempt to cover common formats (GIF,
etc.) here. To
read PDS and VICAR (and many other) formats on Unix systems
running X,
use XV 2.11, available by anonymous FTP from
export.lcs.mit.edu
(18.24.0.12) in contrib/xv-2.11.tar.Z and the other
standard X11 FTP
sites.
The FAQ for the Usenet group alt.binaries.pictures
discusses image
formats and how to get image viewing software. A copy of
this document
is available by anonymous FTP from the Usenet FAQ archives
at
pit-manager.mit.edu (18.72.1.58), in directory
pub/usenet/alt.binaries.pictures.
ONLINE ARCHIVES
NASA AMES
Extensive archives are maintained at NASA Ames and are
available via
anonymous FTP or an email server. These archives include
many images and
a wide variety of documents including this FAQ list, NASA
press
releases, shuttle launch advisories, and mission status
reports. Please
note that these are NOT maintained on an official basis.
FTP users should connect to ames.arc.nasa.gov
(128.102.18.3) and look in
pub/SPACE. pub/SPACE/Index contains a listing of files
available in the
archive (the index is about 200K by itself).
To access the archives by email, send a letter to
archive-server@ames.arc.nasa.gov (or ames!archive-server).
In the
subject of your letter (or in the body), use commands like:
send SPACE Index
send SPACE SHUTTLE/ss01.23.91.
The capitalization of the subdirectory names is important.
All are in
caps. Only text files are handled by the email server at
present; use
one of the FTP email servers described in the introduction
to this
section for images or programs.
The Magellan Venus and Voyager Jupiter, Saturn, and Uranus
CD-ROM image
disks have been put online in the CDROM and CDROM2
directories. The
disks will be rotated on a weekly basis. Thousands of
images are
available in these collections.
The GIF directory contains images in GIF format. The VICAR
directory
contains Magellan images in VICAR format (these are also
available in
the GIF directory). A PC program capable of displaying
these files is
found in the IMDISP directory (see the item "VIEWING
IMAGES" below).
The NASA media guide describes the various NASA centers and
how to
contact their public affairs officers; this may be useful
when pursuing
specific information. It's in MISC/media.guide.
Any problems with the archive server should be reported to
Peter Yee
(yee@ames.arc.nasa.gov).
NASA SPACELINK
SpaceLink is an online service located at Marshall Space
Flight Center
in Huntsville, Alabama. The system is specifically designed
for
teachers. The data base is arranged to provide easy access
to current
and historical information on NASA aeronautics, space
research, and
technology transfer information. Also included are
suggested classroom
activities that incorporate information on NASA projects to
teach a
number of scientific principles. Unlike bulletin board
systems, NASA
Spacelink does not provide for interaction between callers.
However it
does allow teachers and other callers to leave questions
and comments
for NASA which may be answered by regular mail. Messages
are answered
electronically, even to acknowledge requests which will be
fulfilled by
mail. Messages are generally handled the next working day
except during
missions when turnaround times increase. The mail system is
closed- loop
between the user and NASA.
SpaceLink also offers downloadable shareware and public
domain programs
useful for science educators as well as space graphics and
GIF images
from NASA's planetary probes and the Hubble Telescope.
You can dial in at (205)-895-0028 (300/1200/2400/9600(V.32)
baud, 8
bits, no parity, 1 stop bit), or telnet to
spacelink.msfc.nasa.gov
(128.158.13.250, also known as xsl.msfc.nasa.gov) if you're
on the
Internet. Anonymous FTP capability will be offered in the
future.
Most of this information is also available from the Ames
server in
directory SPACELINK.
NATIONAL SPACE SCIENCE DATA CENTER (NSSDC)
The National Space Science Data Center is the official
clearinghouse for
NASA data. The data catalog (*not* the data itself) is
available online.
Internet users can telnet to nssdca.gsfc.nasa.gov
(128.183.36.23) and
log in as 'NODIS' (no password). You can also get the
catalog by sending
email to 'request@nssdc.gsfc.nasa.gov'.
You can also dial in at (301)-286-9000 (300, 1200, or 2400
baud, 8 bits,
no parity, one stop). At the "Enter Number:" prompt, enter
MD and
carriage return. When the system responds "Call Complete,"
enter a few
more carriage returns to get the "Username:" and log in as
'NODIS' (no
password).
The system is menu-driven; topics available as of 4/10/92
are:
1 - Master Directory - NASA & Global Change
2 - Personnel Information Management System
3 - Nimbus-7 GRID TOMS Data
4 - Interplanetary Medium Data (OMNI)
5 - Request data and/or information from NSSDC
6 - Geophysical Models
7 - CANOPUS Newsletter
8 - International Ultraviolet Explorer Data Request
9 - CZCS Browse and Order Utility
10 - Astronomical Data Center (ADC)
11 - STEP Bulletin Board Service
12 - Standards and Technology Information System
Data can be ordered from the NSSDC on CD-ROM and other
formats. Among
the many types of data available are Voyager, Magellan, and
other
planetary images, Earth observation data, and star
catalogs. Viewers for
Macintosh and IBM systems are also available. As an example
of the cost,
an 8 CD set of Voyager images is $75. Data may ordered
online, by email,
or by physical mail. The postal address is:
National Space Science Data Center
Request Coordination Office
Goddard Space Flight Center
Code 633
Greenbelt, MD 20771
Telephone: (301) 286-6695
Email address: request@nssdca.gsfc.nasa.gov
NSSDCA is also an anonymous FTP site, but no comprehensive
list of
what's there is available at present.
SPACE AND PLANETARY IMAGE FACILITY
Available 24 hours a day via anonymous FTP from
pioneer.unm.edu. Has
approximately 150 CD-ROM's full of imagery, raw, and
tabular data. To
start, get the file:
pioneer.unm.edu:pub/info/beginner-info
This will hopefully give you all of the information you
need to get data
from their machine. beginner-info has been translated to
other
languages, you should look inside pub/info for the
particular language
that meets your needs.
Contact help@pioneer.unm.edu.
SPACE TELESCOPE SCIENCE INSTITUTE ELECTRONIC INFORMATION
SERVICE
stsci.edu (130.167.1.2) has a large amount of information
about the
Hubble Space Telescope available by anonymous FTP, such as
status
reports and newsletters, in addition to material oriented
towards HST
observers and proposers. Get the top level README file to
begin with.
Contact Pete Reppert (reppert@stsci.edu) or Chris O'Dea
(odea@stsci.edu).
ASTRONOMICAL DATABASES
The full SAO stellar database is *NOT* available online,
probably due to
the 40 MB size. It may be ordered on magnetic tape from the
NSSDC. A
subset containing position and magnitude only is available
by FTP (see
"Astronomy Programs" below).
nic.funet.fi (128.214.6.100) has a large collection of
astronomical
programs for many types of computers, databases of stars
and deep sky
objects, and general astronomy information in directory
/pub/astro. This
site is mainly for European users, but overseas connections
are
possible.
mandarin.mit.edu (18.82.0.21) has the following data
available via
anonymous FTP in directory /astro: StarChart v3.2, orbital
elements for
bright comets and asteroids, the Yale Bright Star catalog,
Saguaro
Astronomy Club Deepsky and Double Star databases, some PC
astronomy
programs, and possibly more. Get astro/README. Contact
ccount@athena.mit.edu with questions.
The Ames archives contain a database of 8,436 galaxies
including name,
RA, declination, magnitude, and radial velocity in
MISC/galaxy.dat.
Supplied by Wayne Hayes (wayne@csri.utoronto.ca).
iris1.ucis.dal.ca (129.173.18.107) has a number of GIFs
from Voyager,
Hubble, and other sources available by anonymous FTP in
pub/gif (most of
this data is also in SPACE/GIF on the Ames server). Please
restrict
access to 5pm - 8am Atlantic time.
pomona.claremont.edu has the Yale Bright Star catalog for
anonymous FTP
in directory [.YALE_BSC]. Contact James Dishaw
(jdishaw@hmcvax.claremont.edu).
The Hubble Guide Star catalog is available on CD-ROM for
the Mac and PC
for $49.95 US (catalog # ST101).
Astronomical Society of the Pacific
390 Ashton Ave.
San Francisco, CA 94112
Phone: (415) 337-2624 9 AM - 3 PM Pacific Time
FAX: (415) 337-5205
For German (and possibly other European) readers, Jost Jahn
has a
service to distribute astronomical data to interested
amateurs at cost.
About 30-40 catalogs are available for DM 6..8/disk.
Several floppy disk
formats are available. Because of the expense of receiving
email on his
system, he asks that you contact him by physical mail:
Jost Jahn
Neustaedter Strasse 11
W-3123 Bodenteich
GERMANY
Phone: FRG-5824-3197
ASTRONOMY PROGRAMS
Various astronomy-related programs and databases posted to
the net in
the past are archived for anonymous FTP at multiple sites,
including
ftp.uu.net (137.39.1.9). Also see the ASTRO-FTP list posted
to sci.astro
monthly, which is more complete than this list.
Astonomical/Space-related sources of interest in
comp.sources.unix:
Volume 8: phoon moon phase and date routines
Volume 12,13: starchart starchart program & Yale Star
data
Volume 15: moontool shows moon phase picture on Suns
Volume 16: sao reduced SAO catalog
Astonomical/Space-related sources of interest in
comp.sources.misc:
Volume 8: moon another moon phase program
Volume 11: starchart starchart program, version 3.2
Volume 11: n3emo-orbit orbit: track earth satellites
Volume 12: starchart2 starchart program, update to
version 3.2.1
Volume 13: jupmoons plotter for Jupiter's major
moons [in perl]
Volume 13: lunisolar lunisolar (not sure what this
does)
Volume 14: ephem-4.21 astronomical ephemeris, v4.21
Volume 14: n3emo-orbit patch to orbit 3.7
Volume 18: planet planet generation simulator
Elwood Downey (e_downey@tasha.cca.cr.rockwell.com), the
author of
"ephem", has offered to mail copies to people who can't
find it on one
of the archives.
XSAT, an X Window System based satellite tracking program,
is
available by anonymous FTP from export.lcs.mit.edu
(18.24.0.12) in
contrib/xsat1.0.tar.Z. Contact Dave Curry
(davy@ecn.purdue.edu)
for more information.
The "Variable Stars Analysis Software Archive" is available
via
anonymous FTP from kauri.vuw.ac.nz (130.195.11.3) in
directory
pub/astrophys. This is intended for specialists in this
field, and they
would appreciate people from outside New Zealand confining
their FTP
access to the astrophys directory, as they pay a
significant amount for
Internet access. Contents are relatively sparse at present
due to the
youth of the archive - contributions are encouraged.
Contact the archive
administrator, Timothy Banks (bankst@kauri.vuw.ac.nz) for
more
information.
The "IDL Astronomy Users Library" is available by anonymous
FTP from
idlastro.gsfc.nasa.gov (128.183.57.82). This is a central
repository for
general purpose astronomy procedures written in IDL, a
commercial image
processing, plotting, and programming language. Contact
Wayne Landsman
(landsman@stars.gsfc.nasa.gov) for more information.
ORBITAL ELEMENT SETS
The most recent orbital elements from the NASA Prediction
Bulletins are
carried on the Celestial BBS, (513)-427-0674. Documentation
and tracking
software are also available on this system. The Celestial
BBS may be
accessed 24 hours/day at 300, 1200, or 2400 baud using 8
data bits, 1
stop bit, no parity.
Orbital element sets are available via anonymous FTP from
the
following sites:
archive.afit.af.mil (129.92.1.66) NASA,TVRO,Shuttle
directory: /pub/space
ftp.funet.fi
(128.214.6.100) NASA,TVRO,Molczan,CelBBS,
directory: /pub/astro/pc/satel Shuttle (*)
kilroy.jpl.nasa.gov (128.149.1.165) NASA,Molczan
directory: /pub/space/
nachos.ssesco.com (192.55.187.18) NASA,Molczan
directory: /sat_elements
SPACE DIGEST ARCHIVES
Copies of back issues of Space Digest are archived on
LISTSERV@UGA.BITNET. Send mail containing the message
"INDEX SPACE" to
get an index of files; send it the message "GET filename
filetype" to
get a particular file.
LANDSAT AND NASA PHOTOS
You can get black-and-white 1:1M prints, negatives, or
positives for
$10, $18, $12 respectively for any Landsat data more than 2
years old
from EDC, (Eros (Earth Resources Orbiting Satellite) Data
Center). Call
them at (605)-594-6511. You get 80 meter resolution from
the MSS
scanner, 135x180 kilometers on a picture 135x180 mm in
size. I think you
have to select one band from (green, red, near IR, second
near IR), but
I'm not sure. Digitial data is also available at higher
prices.
Transparencies of all NASA photos available to the public
can be
borrowed from the NASA photo archive; you can have copies
or prints
made.
NASA Audio-Visual Facility
918 North Rengstorff Ave
Mountain View, CA 94043
(415)-604-6270
PLANETARY MAPS
The USGS address for maps of the planets is:
U.S. Geological Survey,
Distribution Branch,
Box 25286, Federal Center, Bldg. 41
Denver, CO 80225
Maps cost $2.40 to $3.10 per sheet (a few come in sets of 2
or 3 sheets).
The best global maps of Mars based on Viking images are
1:15,000,000
scale in 3 sheets. These maps are:
I-1535 (2 sheets only) - relief, albedo, names
I-1535
I-1618 (3 sheets) - relief, names
I-2030 (3 sheets) - relief, topographic contours
I-1802-A,B,C (3 sheets) - geology
There are many other maps as well: 30 sheets at 1:5,000,000
scale in
relief, albedo, geology, photomosaic forms (not all 30
sheets available
in all formats); 140 sheets at 1:2,000,000 scale as
photomosaics of the
whole planet, about 100 sheets of interesting sites at
1:500,000 scale
in photomosaic format, and lots of special sheets.
Then there are maps of Mercury, Venus, the Moon, the four
Galilean
Satellites, six moons of Saturn and five of Uranus. [Phil
Stooke
(stooke@vaxr.sscl.uwo.ca), the author of this item, has
offered to
respond to email requests for information on any topic
relating to lunar
and planetary maps.]
COMETARY ORBIT DATA
The Central Bureau for Astronomical Telegrams and the Minor
Planet
Center announce the sixth edition of the Catalogue of
Cometary Orbits in
IAU Circular 4935. The catalogue contains 1292 entries
which represent
all known comets through November 1989 and is 96 pages long.
Non-subscribers to the Circulars may purchase the catalogue
for $15.00
while the cost to subscribers is $7.50. The basic catalogue
in ASCII
along with a program to extract specific orbits and
calculate
ephemerides is available on MS-DOS 5.25-inch 2S2D diskette
at a cost of
$75.00 (the program requires an 8087 math coprocessor). The
catalogue
alone is also available by e-mail for $37.50 or on magnetic
tape for
$300.00.
Except for the printed version of the catalogue, the
various magnetic
media or e-mail forms of the catalogue do not specifically
meantion
non-subscribers. It is possible that these forms of the
catalogue may
not be available to non-subscribers or that their prices
may be more
expensive than those given. Mail requests for specific
information and
orders to:
Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory
Cambridge, MA 02138, USA
NEXT: FAQ #4/15 - Performing calculations and interpreting data
formats
--
_____________________________________________________________________________
| Never play leapfrog with | Craig Fifer |
| a unicorn! -Murphy | 3736 Heritage Road, S.W. |
| | Roanoke, Virginia 24015-4518 |
------------------------------
Date: 7 Nov 92 20:03:21 GMT
From: Claudio Egalon <claudio@nmsb.larc.nasa.gov>
Subject: Hubble's mirror
Newsgroups: sci.astro,sci.space
Henry Spencer is right. Although it was sometime ago that I read an
article in Physics Today- which explained very nicely the real messed
up-, I still recall that there was three diferent instruments that were
used to measure the curvature of the primary mirror. Two of them
used refraction principle and one of them used the reflection
principle (don't remember the details so I may commit some
mistakes. If so, I apologize). The results of the other two instruments
that used the refraction principle to measure the mirror curvature
matched up but... the measurements produced by the one that used
reflection, reflective null corrector, was different and, since it was
thought to be superior to the other two, no one bottered about
finding out why the discrepancy between the measurements... of
course untill they found out that there was something wrong with
Hubble.
*However* as I recall (and I may be wrong) the error in the RNC
came along because the WRONG surface in the instrument was
providing the reflection and not that because the instrument was
built improperly. Aparently there was an scratch in a surface that was
suposed to be black, for absorbing incoming radiation, and it was this
scratch that worked as the WRONG reflecting surface. So, that how
the wrong prescription came about. Another reference for the
investigation on the problem of the mirror was the report put out by
Lew Allen's review board (I guess I have a copy of it at home and I
am confindent that you people can get one from NASA but I do not
know whether they will charge you or not). Maybe, not oddly
enough, there were other complaints about the handling of the
project like people did not like to be bothered with criticism (read
peer review)... So aparently, the problem was both technical and
arrogance.
Claudio O. Egalon
------------------------------
Date: Sat, 7 Nov 1992 16:32:57 GMT
From: David Knapp <knapp@spot.Colorado.EDU>
Subject: Moon can hold its air (was Re: Mars over the Moon???)
Newsgroups: sci.space
In article <1992Nov6.094520.1@fnalc.fnal.gov> higgins@fnalc.fnal.gov (Bill Higgins-- Beam Jockey) writes:
>In article <1ddrqjINNns7@uranium.sto.pdb.sni.de>, sav@nanette.sni.de (Dr.Savory) writes:
>> Any body to be terraformed should have sufficient gravity to retain
>> an atmosphere (obvious?), so exclude the moon, OK ;)
>
>This is unfair to the Moon. If it were magically given an atmosphere,
>the Moon would retain it for a long time, at least thousands of years.
This depends *entirely* on what kind of atmosphere you *put* there.
Sure, an atmosphere of pure Xenon would last a 'long time' but an
atmosphere of H or He would get blown away in a matter of a 'short time'.
>As somebody already mentioned, the Moon is not a good candidate for
>terraforming because it has no large native source of volatiles.
>However, claiming that it can't hang on to an atmosphere is not valid
>for short timescales.
Yes, and according the Heisenberg, we can do *anything* if we make
sure we do it often enough ;-)
>
>It seems to me that anybody who had the technology to give the Moon an
>atmosphere would find it easy to freshen it up every millenium or so
>with new gases...
>
>(Should I mention this? Oh, what the heck, go ahead, Bill. In the
>absolutely clunker TV series *Space 1999* there is an episode where
>precisely this happens: a mysterious alien cylinder suddenly gives the
>Moon a breathable atmosphere. The happy human crew of Moonbase Alpha,
>who have spend their whole TV career huddled underground or working in
>spacesuits, run outside and begin playing volleyball. We see a shot
>from outside a window of Barbara Bain and Martin Landau watching this
>magic moment. Then one of them touches a control AND THE MOONBASE
>ALPHA WINDOW SLIDES OPEN ELECTRICALLY.
>
>(Back in grade school we used to say, "That makes about as much sense
>as a screen door on a submarine.")
>
>Bill Higgins, Beam Jockey |
>Fermi National Accelerator Laboratory | "Get the dinosaurs in, Martha,
>Bitnet: HIGGINS@FNAL.BITNET | they're predicting comets."
>Internet: HIGGINS@FNAL.FNAL.GOV | --Dr. Barry D. Gehm
>SPAN/Hepnet: 43011::HIGGINS |
--
David Knapp University of Colorado, Boulder
Perpetual Student knapp@spot.colorado.edu
------------------------------
Date: Sat, 7 Nov 92 15:40:19 EST
From: John Roberts <roberts@cmr.ncsl.nist.gov>
Subject: Ten embarrassed questions about the moon (very long)
-From: snarfy@cruzio.santa-cruz.ca.us
-Subject: NASA Coverup
-Keywords: Ten Embarrassing Questions about the Moon
-Date: 6 Nov 92 23:37:31 GMT
- As promised ,here come the ...
- TEN EMBARRASSING QUESTIONS ABOUT THE MOON
I expect you'll get a tremendous number of replies - I'll try to answer some
of the easier questions.
It's pretty evident that you've never read the scientific analyses of the
Apollo data. If you really care as much about the moon as you appear to, it
would definitely be worth your while to study some of them - they'd answer
most of your questions. I've been studying "Lunar Science: A Post-Apollo
View" (Stuart Ross Taylor, Pergamon Press, 1975 - QB592.T38,
ISBN 0-08-18274-7). There's also a "Lunar Sourcebook" which is alleged to
be better, but I've never been able to locate a copy. The frequently-asked-
questions list includes many references.
You should also try to watch space shows on TV, like the current series
"Space Age". Best of all would be to get NASA Select (by satellite dish
if necessary), and watch the regular replays of footage from the Apollo
program.
- 1.) Where did the moon come from , and how did it attain it's present
- orbit?
- Scientists have generally offered three major theories to account for
- the moon in orbit around our planet. All three are in serious trouble.
- Amazingly, the least likely theory prior to the Apollo missions emerges
- as the "favorite" theory. Evidence gathered by the Apollo program
- indicate that the moon and the earth differ greatly in composition,
- thereby degrading the two theories that prevailed prior to these flights.
- The first and most popular idea among these scientists was that the moon
- had been born alongside the earth out of the same cloud of gas and dust
- about 4.6 billion years ago. Another theory was that the moon was the
- earth's "child", ripped out of the Pacific basin ,possibly.
- However,evidence gathered by the Apollo missions indicates that the
- moon and earth differ greatly in composition. Scientists now tend to
- lean toward the third theory - that the moon was "captured" by the
- Earth's gravitational field and locked into orbit ages ago.
Your information is out of date. A theory that became widely known only a few
years ago has gained greatly in popularity, and was described on "Space Age"
as the "current most popular theory". According to this model, a roving
body about the size of Mars struck the Earth in a glancing impact. The
heat and kinetic energy of the impact caused the body and much of the outer
part of the Earth to be melted/vaporized and blown out into space. Most of this
material fell back to Earth, much of it was lost into interplanetary space,
but some of it coalesced to form the moon. This accounts for the general
similarity of composition of the Earth and the moon, the fact that the moon
has a very low concentration of volatiles (which would have boiled off in
the intense heating following the impact), the fact that the moon apparently
has no large dense core like the Earth has, and a number of other observed
phenomena.
- 3. Why are moon rocks so much older than earth rocks?
- 99 percent of moon rocks brought back turned out upon analysis to be
- older than 90 percent of the oldest rocks that can be found on earth . If
- we assume that the moon came from a different area of the solar system,
- where the component material might have been different ,this assumption
- would still not account for the disparity in the average age of the
- matter composing the two bodies.
The Earth is geologically active, and its surface is continually being
eroded and replenished. Most of the rocks that were on the surface several
billion years ago no longer exist. The moon has been a "dead world" for
several billion years, and apparently never had a tektonic plate structure.
The only "recent" changes you're likely to encounter are lava flows and
disruption by meteor impacts. It's not the least bit surprising that most
surface moon rocks are older than most surface Earth rocks.
- 4. Why are the "maria" or "lunar seas" located almost entirely on one side
- of the moon?
- The dark areas on the moon are known as "maria" ,some of which form the
- familiar "man in the moon". Maria are significantly absent on the far
- side of the moon. The ones on the near side area consist mainly of lunar
- soil and smaller rocks. Astronauts found it extremely difficult to drill
- into the surface of these dark, plain - like areas. Soil samples weer
- loaded with rare metals and elements like titanium, zirconium, yttruim,
- and berylium. How the moon could have been formed by some random process
- with such high concentrations of rare elements has never been
- satisfactorily explained.
For chemical analysis, you're going to have to read some actual scientific
papers (it won't show up in Time Magazine). Remember that there are many
processes active on the Earth that are not present on the moon. A geologist
investigating the composition of stream beds in California might comment
on the unexpectedly low abundance of gold nuggets, not realizing that they
had been removed by humans. :-)
The maria are lava flows that filled impact craters - there's no reason to
be surprised that flow lava is chemically different from the surrounding
regolith. As for the uneven distribution of the maria, "the apparent
anisotropy of the moon is caused by the lack of mare basalt flooding on the
far side, not by a different cratering history" [above reference].
- 5. Was rustproof iron found on the moon ?
- Samples brought back to earth by both Soviet and American Space Probes
- contain particles of pure iron. The Soviets announced that pure iron
- particles brought back by the remote controlled lunar probe Zond 20 have
- not oxidized even after several years on earth. Pure iron particles that
- do not rust are unheard of in the strange world of science, although
- there is a solid pillar of iron of unknown age near New Delhi ,India,
- that has never rusted ,and no one knows why .
Carbon (which makes iron into steel) is one of the volatiles rare on the moon.
Some forms of iron rust much more slowly than common structural steel.
There are iron bridges in England (and perhaps France) that are 100-200
years old and still in regular use. (Gary could probably add more on this.)
- 6 . Is the core of the moon hot or cold ?
- When the Apollo 15 astronauts used thermal equipment to measure
- temperatures below the surface , they got unusually high readings, which
- indicated high subsurface temperatures near the Apennine mountains. It
- was speculated that , since the presumed density of the moon would
- preclude the possibility of lava flows, magma and the like (volcanism has
- never been observed on the moon) that the high readings could be
- explained by highly radioactive elements just under the surface.
- Actually, the amount of radioactive materials on the SURFACE of the moon
- is "embarrassingly high" . Where did all of this hot ,radioactive
- material ( uranium and thorium ) come from ? And if it came from the
- interior of the moon (very unlikely) ,how did it get to the moon's
- surface?
The total lunar abundance of uranium is thought to be about 60 ppb, and thorium
about 230 ppb. The only figure I could find for the Earth was 2.7 ppb in the
crust. One might explain the difference by greater gravitational differentiation
in the Earth, since it has greater gravity, and spent a much longer period of
time molten. In other words, the Earth might have the same overall
concentration, it's just more concentrated in the interior. (Anyone have an
estimate for the overall concentration of uranium in the Earth, including
the interior?)
The temperature at the center of the moon is thought to be between 1000 C
and 1600 C.
- 7. Were immense clouds of water vapor ever observed on the moon?
- The few lunar excursions indicate that the moon is a very dry world.
- One Lunar expert said that the moon was "a million times as dry as the
- Gobi Desert" . The early Apollo missions did not even find the slightest
- trace of water. But after Apollo 15, NASA experts were stunned when a
- cloud of water vapor more than 100 square miles in size was detected on
- the moon's surface. NASA officials suggested that two tiny tanks,
- abandoned on the moon by U.S. Astronauts, had somehow ruptured. But the
- contents of these tanks could not have produced a cloud of such
- magnitude. The water vapor appears to have come from the moon's interior.
- Mists, clouds and surface changes have been allegedly seen over the years
- by astronomers . For instance , six astronomers in the last century
- claimed to have seen a mist which obscured the details on the floor of
- the crater Plato. Clouds of any kind would be an extremely odd phenomena
- on the moon, because of the supposed low gravity, which presumably could
- not hold an atmosphere. Water trapped beneath the surface, then venting
- by some unknown process , is one possible explanation - but then what (or
- WHO) is "letting off steam"?
There have been a number of reported observations of lunar transient
phenomena. Some possible explanations are outgassing, electrostatic
levitation of lunar dust, and impact of meteors or small comets. If small
comets can hit the Earth, why couldn't they also hit the moon?
- 8. What caused the "Glaze" on the lunar surface?
- Lunar explorations have revealed that much of the lunar surface is
- covered with a glassy glaze , which indicates that the moon's surface has
- been scorched by an unknown source of intense heat . Expert's analysis
- shows that this did not result from massive meteorite impactings . One
- explanation forwarded was that an intense solar flare, of awesome
- proportions , scorched the moon some 30,000 years ago. Scientists have
- remarked that the glaze is similar to the glaze created by atomic weapons
- on earth soil.
There is a considerable amount of glass on the moon. Most of it is in the
form of tiny spheroids, mixed in with the lunar soil, but some of it is in
the form of thin layers splashed over rocks. Close analysis shows that it
is *not* the result of heating by a large solar flare or other external
source of electromagnetic radiation, and the results are very consistent
with melting caused by meteorite impacts.
A very small amount of lunar glass is thought to be associated with lava
flows, like the obsidian on Earth.
- 9. What are "mascons" and how did they get there?
- In 1968 ,tracking data of lunar orbiters first indicated that massive
- concentrations (mascons) existed under the surface of the circular lunar
- maria. NASA even reported that the gravitational pull caused by themwas
- so pronounced that the spacecraft overhead dipped slightly and
- accellerated when flitting by the lunar plain , thus revealing the
- existence of these hidden structures, whatever they are. Calculations
- show that they are enormous concentrations of dense heavy matter centered
- like a bull's eye under the lunar maria. NASA has never offered an
- explanation of their existence.
There have been extensive explanations, though you may never have seen them
in Time Magazine. Lunar mascons are basically a surface phenomenon. Unfilled
lunar craters cause a slight lowering in the local gravity, forming negative
mascons. Craters (and the maria) filled with lava have slightly greater
density than the surrounding ares, and thus form positive mascons. (Generally
these must be greater than about 200 km in diameter.) Large mountain ridges
such as the Apennines have small positive anomalies.
You don't see these phenomena on the Earth, because over the long run it
behaves pretty much like a flexible crust floating on a liquid interior,
so any local area of high density tends to sink down, and any region of low
density tends to bob up, so out at the distance of Earth orbit, the
anomalous effects tend to cancel out - in other words, the Earth is in
isostatic equilibrium. (There are tremendous variations in the density of
the crust - the crust under the continents "goes down" much further than
the crust under the oceans. Actually, the balance of the Earth is not
perfect - northern Europe is still rising following the melting of the
ice after the last ice age, and I believe the center of Greenland is
actually below sea level.)
The lunar highlands are in isostatic equilibrium, implying that they formed
while the interior of the moon was still mostly molten.
- 10. Is there anything "funny" about the moon?
- People who seem to be overly "obsessed" about the moon will often tell
- you that the moon is indeed endowed with "strange" powers that have an
- effect on thier lives. These people are sometimes called "lunatics."
Henry will probably sneer at the following, but I have long thought that the
moon influences living things on the Earth, and the observations stated in
the above reference are certainly remarkable coincidences, if they are just
coincidence. However, I wouldn't make any claim of strange "psychic
connections" - tidal and lighting cycles should be considered the main
causes of any possible influence.
Here's a quote from the above-mentioned book - I haven't made any effort
to find the original references:
...............
- lunar synodical month = lunation = the time between successive new
moons = 29 days, 12 hours, 44 minutes
- sidereal month = average period of revolution of the moon, using a fixed
star as a reference point = 27 days, 7 hours, 43 minutes
xiv:"Among many curious correlations of lunar phases with biological rhythms,
it may be noted that the average duration of human pregnancy is 266 days,
close to the length of nine lunar synodical months (265.8 days) and that
the average duration of the human menstrual cycle is 29.5 days, compared
with the average lunar synodical month of 29.53 days. Menaker, W., and
Menaker, A. (1959) Lunar periodicity in human reproduction, Amer. Jour.
Obstetrics Gynecology. 77:905, and Osley, M., et al. (1973) Ibid., 117:413.
" More sinister correlations, indicating a connection between lunar cycles
and psychiatric disturbances (recalling the ancient association of the moon
and lunacy) are described by Lieber, A.L., and Sherin, C.R. (1972) Amer.
Jour. Psychiatry. 129:69."
...............
As I mentioned before, if you're honestly interested in this subject (and you
did at least make the effort to write a program to work out your calculations,
which shows some level of dedication), then you should make the effort to
find serious sources, and not just rely on the popular media. Popular sources
can be helpful if the topic is current and there is considerable interest in
it - for instance, the Washington Post has had some excellent articles on
the HST mirror defect and Galileo's high gain antenna. But even at their
best, they don't have people who have made a living studying the subject and
really understand it, and they don't have mechanisms to prevent occasional
errors and typos. You also run the risk of getting superficial coverage,
with important details left out. (For instance, coverage of the CFC-ozone
debate was really poor for the first decade or so - only in the last year
or two have the details needed to understand the issue started to get
widespread coverage.)
Also, you really should use your own name. Anonymous posts may be okay in
the conspiracy newsgroup, but in sci.space, people are expected to stand
behind what they say, and to accept the embarrassment if what they post
turns out to be wrong. An anonymous post (especially on a controversial
topic) gives more the impression of an obscene phone call than of a
serious effort to discuss a scientific topic.
I've been working (occasionally) on a long summary of the findings of the
Apollo program. If you'll be patient, I'll try to have it done within a
month or two.
John Roberts
roberts@cmr.ncsl.nist.gov
------------------------------
Date: 7 Nov 92 20:36:08 GMT
From: Claudio Egalon <claudio@nmsb.larc.nasa.gov>
Subject: the Happyface on Mars
Newsgroups: sci.space
The face on Mars makes remind about a suposedly bridge that was
photographed on the Moon before the Moon landing. Of course, the
darned bridge was some kind of optical ilusion. Hope Mars Observer
can put the Face on Mars issue at rest.
------------------------------
Date: Sat, 7 Nov 1992 19:42:04 GMT
From: gawne@stsci.edu
Subject: Viking Photos Shows Evidence of Marsquakes
Newsgroups: sci.space,sci.astro,sci.geo.geology
In article <1992Nov7.041202.16050@organpipe.uug.arizona.edu>,
corleyj@helium.gas.uug.arizona.edu (Jason D Corley ) writes:
> I thought that the Viking landers had picked up only
> minimal Marsquake activities. Has something changed?
>
> I remember reading that only two, and those very slight,
> earthquakes were recorded over the umpteen year run
> of the Viking probes.
>
> Could someone please explain the new data to me (an
> ignorant physics/math undergrad?)
>
> Jason
> Ono-Sendai R&D
The article refered to images taken with the Viking orbiter which
suggest fault boundaries and other evidence of past Marsquakes.
This is separate and distinct from Marsquake data provided by the
Viking landers.
-Bill Gawne, Space Telescope Science Institute
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End of Space Digest Volume 15 : Issue 395
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