archiv~1.txt: SETI CCNet DIGEST 02/03/99

SETI CCNet DIGEST 02/03/99

Larry Klaes ( )
Tue, 02 Mar 1999 10:57:55 -0500

>From: Benny J Peiser <>
>Subject: CCNet DIGEST 02/03/99
>Date: Tue, 2 Mar 1999 10:27:49 -0500 (EST)
>Priority: NORMAL
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>CCNet DIGEST, 2 March 1999
> "Finding something is not the same as discovering what is found.
> The more astronomers study the growing evidence of extra-solar
> planets, the less the planets resemble anything in the one
> planetary system they had known and had based their theories on:
> the Sun's family of planets." (The New York Times, 2 March 1999)
> Andrea Milani Comparetti <>
> Tony Ortega, Astronomy Magazine, April 1999
> The New York Times, March 2, 1999
>>From Andrea Milani Comparetti <>
>Dear OrbFitters and dear friends,
>This message announces the new and significantly improved
>distribution 1.9.0 of the free software OrbFit. Although there are
>also improvements in the algorithms, from the user's point of view
>the main improvements are a user-friendly installation procedure,
>online help facilities, and the possibility to install on many more
>different computers and operating systems (notably WINDOWS).
>The purpose of the software system we are distributing, maintaining
>and continously upgrading, is to make available to observers of
>asteroids an easy to use but accurate and reliable software to
>compute preliminary orbits, ephemerides, improved orbits (by
>differential corrections), identifications, and other auxiliary
>functions, to allow the processing of astrometric observations and
>the planning of observational campaigns (typically to recover lost
>Main improvements with respect to 1.8.0 are:
>1) The online hypertext help has been fully restructured, and is now
>a user manual including all the instruction to upload, install, and
>start using the software.
>2) Absolute magnitude (that is more or less size) is now
>automatically esitmated every time a new orbit is computed.
>3) The input/output of observations has been fully restructured. We
>now provide a new file format (.rwo) containing Residuals, Weights
>(including rejection flags) and Observations. This can be used as
>input, although the MPC format (.obs) files are also accepted, with a
>sophisticated logic to control the priority.
>4) A Windows version, running under Windows95, Windows98 and Windows
>NT is now available as an executable; we compile the Windows version
>from the same source directories, by using Digital Visual Fortran 6.0
>and the NMAKE utility.
>5) We have added a jpleph directory under ./src. The Makefile and
>documentation there are intended to simplify (a bit) the task of
>creating binary format JPL Ephemerides on your machine.
>6) We are now supplying binary ephemerides for Windows and Linux at
>our ftp site: .
>We are presently working toward several improvements, described in
>the file README.workinprog which is enclosed with the distribution;
>the most urgent one is to generate a better graphics, especially for
>the WINDOWS version for which the graphics output is not available
>The software can be obtained at
>A README file to be found therein provides all the necessary
>instruction for installation on all flavours of UNIX and WINDOWS
>This software system has been developed by a consortium including A.
>Milani and S. Chesley (Pisa University), M. Carpino (Astronomical
>Observatory Milano/Brera), Z. Knezevic (Astronomical Observatory
>Belgrade) and G. B. Valsecchi (CNR Rome).
>Copyright (C) 1997-1999 OrbFit Consortium
>This program is free software; you can redistribute it and/or modify
>it under the terms of the GNU General Public License as published by
>the Free Software Foundation; either version 2 of the License, or
>(at your option) any later version.
>To contact us:
>March 1, 1999
>LONDON (CNN) -- By now, you have probably heard the story of Homer
>Hickam Jr.
>Born and raised in a tiny West Virginia coal town, a teen-aged Hickam
>looked to the night sky after the launch of Sputnik in October of 1957,
>hoping to catch a glimpse of the 184 pound satellite as it streaked by.
>He never saw it, but like the rest of the world, he heard those
>strangely menacing beeps, and realized in an instant what it meant for
>the world and where he wanted to be in it. Homer Hickam knew he wanted
>to work for NASA and be one of Wernher von Braun's boys. He wanted to
>build rockets. And so he got to work.
>Over the objection of his coal-mining father, but with some
>encouragement from an understanding mother and teacher, he and some
>friends began building model rockets -- with sometimes frightening,
>sometimes comical, every now and then, stunningly successful results.
>Ultimately, it was Hickam's ticket out of Coalwood. He ended up working
>for NASA as an engineer -- his rocket projects growing to a size and
>complexity that he could not have imagined as he gazed into that October
>That, of course, is the title of the Hollywood version of Hickam's
>charming memoir "Rocket Boys." (In case you haven't noticed -- "October
>Sky" is an anagram of the book title). I haven't seen the movie yet,
>but started the book before I left for London, and have been savoring
>it during every free moment I get.
>I was thinking about Hickam's book earlier this week when I visited a
>small space hardware manufacturer west of here (in Newbury) called
>Space Innovations Ltd.
>SIL's 50 employees design small satellites (able to carry 100 to 600
>pound payloads) as well as X- and S-band transmitters and receivers to
>keep those satellites in touch with their owners.
>The owner of the company is an intriguing American entrepreneur by the
>name of Jim Benson. Producer Linda Saether and I are profiling him for
>an upcoming piece on "NewsStand/Fortune."
>Benson's San Diego based company SpaceDev is the world's first
>commercial space exploration company. He's got some big plans for
>making money on the exploration and exploitation of space -- including
>sending a small satellite to a near-Earth asteroid in late 2000.
>He is convinced he can turn a profit on this venture by selling rides
>for scientific instruments to a government, a company or a university.
>But what really caught my attention is what he'd like to do next.
>When the science mission is complete, the SpaceDev Near Earth Asteroid
>Prospector (NEAP) satellite will make a soft landing on the asteroid
>Nereus, laying the groundwork for Benson to stake his claim.
>Benson eventually would like to mine Nereus for its resources. Can you
>guess what resource might be most precious on an asteroid? It's water.
>That's right, water. After all, remember what rocket fuel is: hydrogen
>and oxygen. H20 -- ice -- might prove, in space, all that glitters
>really isn't gold. Who knows? Jim Benson might one day become the John
>D. Rockefeller of the space revolution.
>In fact, Jim Benson is certain there will be a revolution in space in
>the next decade. He compares it to the industry where he made his
>fortune: computers. The relentless miniaturization of electronics
>brought down mainframe giants like Sperry, Univac, Burroughs and
>Honeywell. Could small, inexpensive satellites do the same to the big
>aerospace contractors? Benson thinks so. And he is putting his money
>where his mouth is.
>I was wrestling with these revelations when I met Stephen Gardner, one
>of SIL's young aerospace engineers. He looked up from the computer
>image of the tiny satellite he is helping design and he told me: "It's
>really come full circle. Right back to Sputnik-size spacecraft."
>Sputnik-sized yes, but able to do so much more than beep. I wonder who
>now realizes, in an instant, what this means for the world. Will bright
>teen-agers one day long to be one of Jim Benson's boys?
>Copyright 1999, CNN
>Tony Ortega
>Astronomy Magazine, April 1999
>The Minor Planet Center (MPC) at the Harvard-Smithsonian Center for
>Astrophysics in Cambridge, Massachusetts, receives about 10,000
>position reports of known and new asteroids and comets a month. But
>beginning in March 1998, a single Air Force telescope has swamped the
>MPC. The telescope submitted 160,000 observations in September alone
>-- sending a shudder of disbelief through the world's
>astronomical-research community.
>The little known, high-tech military telescope run by scientists from
>the Massachusetts Institute of Technology's Lincoln Laboratory has,
>virtually overnight, become the world's preeminent tool for finding
>asteroids and comets. The LINEAR observatory, short for Lincoln
>Near-Earth Asteroid Research, uses a state-of-the-art telescope with
>super-fast light detectors to find so many asteroids that astronomers
>don't even try to keep track of them all. It is finding such an
>abundance of near-Earth asteroids, main-belt asteroids, and comets
>that astronomers are stunned. Comets named after people could be a
>thing of the past.
>Until [my] visit, MIT's Lincoln Laboratory had permitted only one
>film crew to see the telescope. Grant Stokes, an astrophysicist who
>runs the program from MIT, also in Cambridge, agreed to let me see
>the installation. It is located in a patrolled, high-security area on
>the White Sands Missile Range about a mile from Trinity Site, where
>the first nuclear bomb was detonated on July 16, 1945.
>The LINEAR observatory is a squat, sheet-metal building surrounded by
>eight small observatory domes. Most of them are used in Ground-based
>Electro-Optical Deep Space Surveillance, or GEODSS, a program that
>keeps track of about 9,500 man-made objects that orbit Earth. With
>GEODSS, the United States can see everything from astronaut gloves to
>foreign spy satellites whizzing by overhead. LINEAR uses just one of
>the telescopes in one of the domes.
>The LINEAR CCD, or charge-coupled device light detector, has 5
>million pixels, or picture elements, arranged in a 1960- by
>2560-pixel array. The LINEAR chip is back-illuminated, meaning that
>instead of losing precious light-gathering potential to a lattice of
>wiring that connects pixels, electrical connectors that connect each
>pixel are etched into the chip. As a result, the chip is as thick as
>aluminum foil and has twice the light-gathering capacity of a
>conventional CCD.
>Astronomers wait up to two minutes for data from a conventional CCD
>to be recorded, whereas the LINEAR CCD reads all of its pixels in a
>few milliseconds. Stokes showed me how the chip manages it. Above and
>below the light-gathering area there are highly reflective areas that
>he calls "frame stores." They're effectively 5,000 parallel channels
>through which the information stored on the millions of pixels can be
>rapidly shifted.
>The information is read by a computer via eight parallel channels of
>fiber optic lines. The LINEAR chip soaks up enough starlight to
>detect faint, 19th-magnitude stars in only 10 seconds. The chip then
>dumps the information into a computer so fast, the chip is ready for
>the next frame without having to use a shutter.
>LINEAR's 1-meter telescope is housed in a small dome outside the
>metal building. Eric Pearce, the on-site astronomer who manages the
>facility, simply removes a cloth cover before working each evening.
>The scope runs itself automatically. The telescope's mount was built
>for quick slewing-and-stopping. It makes asteroid detection seem like
>child's play. Taking rapid snapshots, it has time to take five images
>of each piece of sky. The scope photographs most of the night sky
>during 10 nights of observing each month.
>Powerful computers layer the five pieces on top of one another. With
>a push of a button, software gobbles up thousands of stars on the
>screen. Suddenly, the only objects remaining on the screen are a
>handful of objects the software decides are asteroids and cornets..
>"If you're willing to take five frames, the software has a very good
>performance with respect to probability of discovery and a very low
>false-alarm rate," says Stokes in his understated, technical way.
>"The Minor Planet Center tells us that when we sweep through an area
>we find everything we're supposed to find: everything they know
>about, plus stuff they don't know about."
>The results have been astonishing. Since LINEAR went on line at full
>speed in March 1998, the project has swamped the MPC with new
>discoveries. Of the 147 total near-Earth objects found in all
>observatories between March and November, LINEAR discovered 102 of
>them. Of the objects discovered during that period that were 0.6
>miles (1 km) or larger -- the size considered large enough to cause
>climatic disruptions on Earth -- LINEAR discovered 26 of the total
>38. Of 28 comets discovered in the same period, LINEAR had its
>name attached to 13 of them.
>By January 3, overworked orbit calculators at the MPC had given
>designations to 19,293 new asteroids discovered by LINEAR in only 10
>months of operation. That is only 5,984 fewer asteroids than
>Spacewatch [at the University of Arizona] discovered in 16 years.
>"The MPC is going to have to get some new computers," Stokes says
>with a satisfied grin.
>>From The New York Times, March 2, 1999
>The discovery of planets around other stars has made Epicureans of
>astronomers. Not that they now put out the fine silver, pop the cork
>and dress for dinner by candlelight every long night under the
>observatory dome; they are still unwrapping their tired sandwiches and
>tearing open the corn chips, thank you. But nowadays their tastes run
>to the cosmic musings of the eponymous founder of Epicurean philosophy.
>Epicurus, a Greek philosopher in the fourth century B.C., did not
>explicitly predict the existence of planets around stars other than the
>Sun, but he believed in an infinity of worlds, meaning other ordered
>systems beyond the visible universe as it was then conceived. This
>contrasted to the Earth-centered cosmos of the contemporary Aristotle,
>whose cosmology prevailed in Western thought for more than two
>Only in the last three years have astronomers established the reality
>of latter-day Epicurean speculations about a plurality of worlds, which
>in recent centuries came to mean planets beyond the solar system, some
>possibly inhabited. But while astronomers tip their hats to Epicurus,
>they just wish he had advised them how to make sense of the distant
>planets being detected by their telescopes.
>Finding something is not the same as discovering what is found. The
>more astronomers study the growing evidence of extra-solar planets, the
>less the planets resemble anything in the one planetary system they had
>known and had based their theories on: the Sun's family of planets.
>At last count, astronomers in the United States and Europe had observed
>18 nearby Sunlike stars showing telltale motions from the gravity of
>large, unseen planets orbiting them, and they fully expect to find
>more. Yet they suspect they have seen enough to begin rethinking how
>nature creates and destroys planets and choreographs their orbital
>Nine of the objects hug closer to their parent stars than Mercury is to
>the Sun, closer than standard theory predicted planets could be; one is
>so near that it makes a complete revolution -- its full year -- every
>3.1 Earth days. The other nine travel unusually elliptical, or
>oval-shaped, orbits, several of them plunging in relatively close to
>their stars and then swinging far out again; orbits in the solar system
>are almost circular. Several extrasolar planets are at least three
>times as massive as Jupiter, the solar system's giant, and one is
>estimated to have 11 times the Jovian mass -- raising questions about
>how massive can a planet be.
>Dr. Geoffrey W. Marcy, the astronomer at San Francisco State University
>who has had a hand in most of the discoveries, is as surprised as
>anyone. "A trend is now being stamped on these discoveries that we
>thought, frankly, would go away," he said.
>But it has not, and questions pile up. Many stars may have planets, as
>the discoveries suggest, but is there a typical pattern? Could the
>solar system be an oddball? If so, does that diminish prospects for
>intelligent life's existence elsewhere in the universe?
>Dr. Alan P. Boss, a theorist of planetary systems at the Carnegie
>Institution of Washington, thinks astronomers will eventually "find
>systems that look something like our solar system." He acknowledged
>that they would also "find many more surprises to make us rethink what
>we're doing."
>Astronomers concede that so far their sampling of extrasolar planets
>may not be representative, only a reflection of detection capabilities.
>They have no proof yet of another Sunlike star with more than one
>planet, or with anything considerably smaller than Jupiter. But it is
>easier to observe the gravitational effects of Jupiter-class planets,
>especially those extremely close to the host stars. It takes years of
>repeated observations to gather reliable evidence for planets traveling
>the longer orbits at much greater distances from a star. And it is not
>yet possible to detect in any orbit, near or far, an Earth-size or even
>Saturn-size planet.
>The newest detection, announced last month, was of the smallest
>extrasolar planet yet examined, one that has less than half of
>Jupiter's mass and is only 1.4 times more massive than Saturn. The
>planet, in a tight 3.5-day orbit around the star HD 75289, was found by
>a team of Swiss astronomers led by Dr. Michel Mayor of the Geneva
>Observatory, who in October 1995 reported the first confirmed planet
>around another star like the Sun.
>In the next decade, the National Aeronautics and Space Administration
>expects to fly several space telescopes for a more comprehensive survey
>of planets around nearby stars. On the drawing board is an advanced
>satellite called Planet Finder that someday could send back the first
>pictures of Earth-type extrasolar planets.
>"It's a terribly exciting field right now," said Dr. Stephen Lubow, an
>astrophysicist at the Space Telescope Science Institute in Baltimore.
>"The discoveries have really opened a new window on the nature of
>planetary objects in the universe."
>The first discoveries of extrasolar planets should have prepared
>astronomers to expect the unexpected. In 1992, radio astronomers
>reported the first strong evidence of such objects, but the two planets
>were not orbiting a normal star. They accompanied a pulsar, the dense
>remnant of an exploded star and not a neighborhood likely to be
>hospitable to life.
>Dr. Mayor and Dr. Didier Queloz of Switzerland then detected a planet
>around 51 Pegasi, a solar-type star, and this was soon confirmed by Dr..
>Marcy and a colleague, Dr. R. Paul Butler. The first accepted planet of
>an ordinary star excited and puzzled astronomers. Both teams were
>startled to find that the planet, about half the mass of Jupiter, was
>in an almost circular orbit less than one-sixth the equivalent distance
>of Mercury to the Sun.
>Ever since then, theorists have been puzzling over how several of the
>large planets -- dubbed "hot Jupiters" because of their proximity to
>the intense heat of their stars -- could be where they are. Why were
>they not out somewhere the equivalent of the Jupiter-Sun distance?
>Because known physical laws rule out the formation of large planets so
>close to a star, theorists think they formed in a more benign
>environment far out and migrated inward. The unlucky ones probably
>crashed into their stars. Others somehow settled into cozy orbits at
>less than one-fourth of an astronomical unit, the standard measure of
>planetary distances in which one unit is the distance from the Sun to
>Earth, or 93 million miles.
>The migration theory that receives the widest attention was proposed by
>Dr. Douglas Lin of the University of California at Santa Cruz, Dr.
>Peter Bodenheimer of the university's Santa Barbara campus and Dr.
>Derek Richardson of the University of Washington.
>Their concept drew on research by Dr. William Ward of the Southwest
>Research Institute in Boulder, Colo., and ideas developed to explain
>the interplay of the rings and satellites around Saturn.
>According to prevailing theory, a planetary system forms from a disk of
>gas, dust and chunks of rock that surrounds a newborn star. The star's
>heat would drive gas out of the inner disk and prevent the huge gaseous
>planets from forming there. They would instead develop in the gas-rich
>outer disk.
>In the early period of planetary formation, the disk would still be
>thick with gas and other material. Drag from the disk material and its
>general inward flow, caused by the young star's gravity, would have
>drawn many of the large planets out of their original orbits.
>Astrophysicists postulate several phenomena that prevent at least some
>of the planets from plunging all the way into their stars. One is that
>when the star was young it was spinning more rapidly, creating tidal
>forces that arrest a planet's migration short of catastrophe. Another
>idea, suggested by some observations of young stars, is based on the
>likelihood that the gravity or magnetic forces of newly formed stars
>soon sweep away disk material from their nearest surroundings, leaving
>a doughnut hole at the center. Here the migrating planets could settle
>into parking orbits.
>Dr. Lin, pondering why something like this did not happen to Jupiter,
>decided that previous Jupiters in the solar system probably migrated to
>their destruction. Jupiter and the other solar planets represent the
>last generation, created as the planetary disk was dissipating and
>leaving more stable conditions. Or perhaps the solar system's
>protoplanetary disk never had enough gas and dust to perturb the orbits
>of its new planets.
>A more recent variation on the migration theory was introduced by a
>team of theorists at the University of Toronto led by Dr. Norman
>Murray. In the early formative period, they argue, planets might be
>orbiting through a disk of planetesimals, small rocky objects colliding
>with or being ejected by the planets. The destabilizing interactions
>with the planetesimals could push the newly forming planets toward
>their stars.
>One of the first detections by the Marcy-Butler team, announced in
>January 1996, introduced another puzzlement. The planet around 70
>Virginis was more than seven times the Jovian mass and not as close to
>its star as many others, but its orbit was highly elliptical. Other
>planet discoveries revealed similar characteristics. The one around 16
>Cygni B has the most elliptical orbit; if it was in the solar system,
>the massive planet would sweep in as close as Venus and retreat out as
>far as the asteroid belt between Mars and Jupiter.
>Some powerful gravitational forces, astrophysicists said, must have
>perturbed the planets' orbits. A star passing too close could knock a
>planet out of its generally circular orbit.
>Or the planet's own star could be part of a binary system, one of two
>stars in gravitational embrace, and the companion star could be
>unsettling the nearby planets. But not all the planets in elliptical
>orbits are in binary systems.
>Dr. Frederic A. Rasio of the Massachusetts Institute of Technology,
>working with Dr. Eric Ford, has proposed a concept of gravitational
>scattering that, he said, "explains very naturally and simply planets
>in wide eccentric orbits."
>The idea involves two or more huge planets orbiting in close proximity
>so that they generate a kind of gravitational slingshot. The forces
>might sling one planet off on an elongated orbit to the inner planetary
>system, while the other might fly off toward the fringes of the system,
>perhaps escaping into interstellar space.
>Such a scenario could also explain why astronomers have yet to find
>more than one planet around a single star. Any other large ones there
>were catapulted into deeper, longer orbits and would be undetectable in
>the brief time astronomers have been looking for evidence of extrasolar
>Just one giant planet on an elongated orbit, moreover, would probably
>spell doom for smaller planets as it crosses their paths time and
>again, scattering or destroying them in the turbulence of their
>gravitational wakes.
>"If our Jupiter were in an eccentric orbit, the Earth and Mars would
>likely be gravitationally scattered out of the solar system," Dr. Marcy
>said. "Thus our existence depends on both Jupiter and Earth being in
>mutually stable, circular orbits."
>The implications are profound for the search for extraterrestrial life.
>"The big bullies may wipe clean the terrestrial planets in those
>planetary systems, rendering them void of any Earth analogues," the
>astronomer said.
>Dr. Marcy takes an optimistic view. Of all the Sunlike stars that have
>been studied so far by planet seekers, he said, only 5 percent have
>been found to have Jupiter-mass planets in such dangerously eccentric
>That leaves 95 percent of stars that may be free of these wrecking
>forces and so could harbor habitable planets.
>All theories to explain the newly detected extrasolar planets, Dr.
>Rasio said, remain at "the hand-waving level." Theorists are severely
>limited by observations, which have yet to reveal more than one planet
>around a single normal star. The two or three objects around a pulsar
>offer little insight. Earlier reports of possibly two planets around
>the star Lalande 21185 have not been confirmed.
>"If you only see one companion to a star, you cannot say that this is a
>planetary system," Dr. Rasio said. "That's going to be the next major
>breakthrough, finding multiple planets and then putting some
>constraints on the properties and behaviors of other planetary systems.
>That's our holy grail."
>Planet hunters like Dr. Marcy are looking. They speak of some
>interesting hints, but nothing yet for the new Epicureans of astronomy
>to feast on.
>Copyright 1999, The New York Times Newspapers Ltd.
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