Sojourner Online

SOJOURNER

The Newsletter of

the Seattle Chapter

The National Space Society

NSS Seattle

ปปปปปปปปปปปปปปปปปปปปป August 1998 ซซซซซซซซซซซซซซซซซซซซซ

The National Space Society is an international membership group

dedicated to furthering the exploration and development of space. The Seattle

chapter mission is to facilitate Space Activism and all pro-Space activities; and to provide

a gathering place for space enthusiasts to meet, exchange information and ideas.

President:   Vince Creisler vincelc@hotmail.com
Vice President: Chris Vancil    CLVANCIL@aol.com
Secretary:      Randy Rumley    rjrumley@juno.com
Treasurer:   David Stuart        xsxs80a@prodigy.com
Editor:    Christopher Erickson aster@wolfenet.com

----------Board of Directors---------

Kelly Caviezel Gary Harrison Christopher Erickson

Susan Harrison Toni Rusi

------------Advisors------------

Terry Burlison

Chapter meetings are held at 7:00 PM on the second Saturday of each month, at the

Museum of Flight; parking is available in the lot North of the museum. To receive

information regarding upcoming events please send your name and addresses

to: Randy Rumley; 12008 S.E. 223rd Drive Kent, WA 98031

XXI

soทjourn(s๒ j๛rn), to stay for a time in a place; live temporarily.

Message from the President

For me, Alan Shepard's recent death brings back memories of watching live "space-shots" on a black and white TV. The excitement of Mercury, Gemini and Apollo flights were a big part of childhood in the 1960's. Moon Bases and manned Mars missions seemed certainties before the century's end. The watered-down Space Age that has prevailed, focused on Space Shuttles, and Space Stations produces impressive achievements, but lacks grandeur.

Today's children grow up in a nation striving toward no goal, proclaiming no vision of the future or standing for any ideal. Goals, visions and ideals are what Alan Shepard and his fellow Space pioneers gave to America. Their efforts were a counter-point to the strife and disillusionment of the social upheaval that erupted in the 1960's. What a dismal time that would have been without them--and what a dismal future we would be living in now.

Vince Creisler

President, NSS Seattle

A few new URLs: (more on back page)

Satellite photo server: http://www.terraserver.microsoft.com/

Earth/Moon viewer: http://www.fourmilab.ch/earthview/vplanet.html

Satellite tracker: http://liftoff.msfc.nasa.gov/academy/rocket_sci/satellites/

A NASA style gift shop: http://www.thespaceshop.com

Ben's Space Page -- Linking Hyper Space to Outer Space: http://www.skypoint.com/~benhuset/

Bill Harwood's Space Space: http://uttm.com/space/

The NASA Space Weather Bureau: http://www.spaceweather.com/

For our ever-growing list of URLs on the web, visit our web site. Chris Vancil keeps it updated. Including online versions of this newsletter.

http:// nss.ac/wa/seattle/index.html

August 8, 1998

Meeting

Our speaker will be Professor Jim Tillman of the University of Washington. He will be discussing development of the 'Live from Mars' educational outreach component of 'Live from Earth and Mars', Interactions with students during Pathfinder, Meteorological and photographic observations of Mars, Impressions of mission operations, his participation in the European NetLander proposal for the Mars Express program, and Future educational initiatives. I know it sounds like a lot, and it is. He has had a busy year, what with Pathfinder and Surveyor data to pour over.

Meeting Summary

July11, 1998

Last months speaker was Robert P. Hoyt, Ph.D, of Tethers Unlimited, Inc. Tethers unlimited now has more projects in the works. The major focus currently is a system to de-orbit dead satellites (i.e. satellites that no longer can communicate with the ground). The way this would work would be to use the earth's magnetic field to interact with a tether sent out below the spacecraft. This is called Electro-magnetic drag. The method seems to be rooted in some solid physics, and should work quite well. They do have some hurdles to overcome, tests need to be done in orbit on a piggyback ride on another satellite, and some technical areas have to be clarified. They currently have the deployer designed (by Tether Applications), and have found ways to manufacture the tethers themselves at a textile plant.

He also gave an interesting discussion on where his and Robert Forwards work with Tethers to the mood has gone, and went over relative strengths of various tether materials that are currently, or soon to be available. This talk will air on the 16th on public access channel. 29, 5:00pm.

Randy J. Rumley

Secretary, NSS Seattle

Cometary Impact with Earth unlikely in the next 500,000 years

From: Ohio State University

Written by Earle Holland, (614) 292-8384; holland.8@osu.edu

COLUMBUS, Ohio -- Contrary to Hollywood's latest predictions, it is highly unlikely that a comet will rain death and destruction on the earth during the next half-million years, according to a new study.

Jay Frogel and Andrew Gould, professor and associate professor of astronomy at Ohio State, were looking for evidence of the so-called "death star" scenario where a passing star might alter the current orbits of comets near our solar system and send them our way. The review of the motions of thousands of nearby stars failed to show any rogue stars capable of pulling comets out of their orbits and into the earth's path.

There is ample evidence both on earth and on other planets, they say, that shows comets and asteroids have impacted with devastating results. Two new movies -- "Deep Impact" and "Armageddon" -- depend on this premise for their drama. Frogel's interest, however, was spurred by geological evidence of such past impacts, he says, and not by the new movies.

He and Gould turned to a relatively new resource to conduct their search -- the HIPPARCOS catalogue. In 1989, the European Space Agency launched the HIPPARCOS satellite with its mission to accurately measure the location and motion of more than 120,000 stars.

Astronomers believe a massive cloud of comets -- the Oort Cloud -- lies as much as 100,000 AUs out from the sun, surrounding our solar system. If a star passed through that cloud, its gravitational field might nudge a comet out of orbit and towards the earth.

Frogel and Gould looked in the HIPPARCOS Catalogue specifically for stars with near zero proper motion -- stars that were either coming directly in our direction, or moving directly away. Any star that had already passed would appear to be moving directly away.

"For all intents and purposes, you should just see a star that appeared not to be moving at all," Gould said. The one potential candidate the researchers did find turned out to be a star previously identified by other scientists. They failed also to find evidence of stars that may have already passed nearby.

Gould's analysis of the HIPPARCOS catalogue showed that it should be sensitive enough to detect zero proper motion of any stars brighter than 8th magnitude. Eighth magnitude stars appear about 25 times fainter than those visible to the naked eye.

Gould said that these bright stars are important candidates for the death star scenario. "They're bright either because they are close by or because of their size," he said. The larger the star, the greater it's gravitational effect might be on nearby comets.

"We showed that theoretically, about 96 percent of the possible damaging events (the passing of such stars) should show up in the HIPPARCOS catalogue," Gould said. They had defined a "damaging event" as a star passing within 20,000 AUs of the sun.

Frogel and Gould are cautious with their predictions -- "We can't guarantee that a comet won't hit the earth next year." Their analysis of the catalogue, however, makes it "unlikely that a major (comet) shower will occur in the next half-million years."

Gould said, "The chance that a big enough star to cause significant damage would go through (our region) in the next 10 million years is extremely small."

Frogel said he and Gould are confident about their analysis of the HIPPARCOS catalogue. The next step would be to seek a "death star" candidate among stars that were too faint to be included in HIPPARCOS.

Another satellite -- GAIA -- has been proposed by ESA, which would measure the motions of 50 million objects, including stars as faint as 15th magnitude. If approved, GAIA would be launched no sooner than the year 2009.

Some support for this research came from the National Science Foundation.

In Memoriam: Alan Shepard

Alan B. Shepard

America's first astronaut to fly died July 28, 1998 at the age of 74. In 1961, Alan Shepard became the first American in space. Even though his flight was only 15 minutes long (and several hours on the pad), he helped galvanize President Kennedy and America to shoot for the moon.

10 years later, after overseeing the Astronaut office for NASA, he overcame the ear condition that had grounded him, and went to the moon on Apollo 14. After the Apollo 13 troubles, NASA needed a perfect flight to keep their budget. Shepard and Apollo 14 gave as much as they could to accomplish that. After landing at Fra Mauro, they collected samples and doing other science before leaving some 33 hours later.

Of course Alan Shepard is also the only golfer to ever take a swing in 1/8 g. Hopefully someone will be able to finish out the lunar 18 in the future. I think the Alan Shepard golf course on the moon would be a fitting memorial. It would show that more than 12 people would eventually make it to the moon.

It is good to reflect on the passing of someone who saw action in WWII, performed as a Test pilot for the Navy, and was one of the few to walk the surface of another world. It was a very memorable life.

Randy Rumley

Space Station Votes

Thursday, July 30, 1998

NASA, space station budget passes U.S. House

The U.S. House of Representatives on Wednesday defeated the annual attempt by Rep. Tim Roemer, D-Ind., to kill the International Space Station.

The failed amendment to NASA's budget, which would have ended funding for the program, was rejected by a vote of 109 to 323. Those voting for the amendment included 47 Republicans, 61 Democrats and one Independent.

Voting against were 179 Republicans and 144 Democrats.

Later in the evening, the House passed the overall-spending bill that included NASA. The measure gives the space agency $13.3 billion for Fiscal Year 1999, which starts Oct. 1.

Pioneer 10

Status Updated

1 August 1998

(Launched 2 March 1972)

Distance from Sun (1 August 1998): 70.58 AU Speed relative to the Sun: 12.24 km/sec (27,380 mph) Distance from Earth: 10.61 billion kilometers (6.595 billion miles) Round-trip Light Time: 19 hours 40 minutes

PIONEER 10 JUST WON'T QUIT! We have just successfully completed the fourth precession maneuver in the past year and a half to point Pioneer 10 toward Earth by cycling the transmitter off and on. This was a procedure that naysayers doomed to failure for a 25+ year old TWT predicting that such a turn-off and start-again would shatter the mechanism. But it was either try it or lose the antenna pointing towards Earth. Needless to say, even experts can be wrong. The mission formally ended on 31 March 1997 when funding ended in favor of more scientifically productive Heliospheric missions. However, a waiver was given to operate Pioneer 10 as part of the Lunar Prospector controller training program as long as other NASA missions were not interfered with. Pioneer 10 has continued at a much reduced activity level under those guidelines. We are deeply grateful for the gracious way that the Lunar Prospector staff has managed this extra burden on their time.

The spacecraft is at a distance of 6.6 Billion miles (71 AUs) and is the farthest out in the opposite direction to which the Sun moves. Voyager 1 passed Pioneer 10 in mileage out of the Solar System earlier this year but is traveling in the opposite direction. AND WE ARE STILL GETTING SCIENCE DATA! The low-power Geiger-Tube-Telescope instrument still yields valuable scientific data. We also receive data from the Charged Particle Instrument but only for a few hours each week to conserve battery power on Pioneer 10. Tracking of Pioneer is expected to continue for at least another six months under the current pointing arrangements. The battery reading is very low - perhaps at a minimum. Pioneer 10 by the grace of God persists longer than ever conceived or expected.

Pioneer 10 will continue into interstellar space, heading generally for the red star Aldebaran, which forms the eye of Taurus (The Bull). Aldebaran is about 68 light years away and it will take Pioneer over 2 million years to reach it.

Pioneer 11

(Launched 5 April 1973)

The Mission of Pioneer 11 has ended. Its RTG power source is exhausted.

The last communication from Pioneer 11 was received in November 1995, shortly before the Earth's motion carried it out of view of the spacecraft antenna.

The spacecraft is headed toward the constellation of Aquila (The Eagle), Northwest of the constellation of Sagittarius. Pioneer 11 may pass near one of the stars in the constellation in about 4 million years.

Some conversion factors (more later):

AU (Astronomical Unit) = 1 earth radii (distance from earth to sun = 92,955,734 miles

[149,597,800 km]

1 km (kilometer) = 0.621 mi.

1 mi. (mile) = 1.609 km

Km/s Kilometers per second

1 m (meter) = 3.281 feet

1 ft (feet) = 0.3048 m

1 cm (centimeter) = 0.394 in

1 in (inch) = 2.54 cm

1 kg (kilogram) = 2.205 lb.

1 lb. (pound) = 0.4536 kg

1 Metric Ton = 1000 kg = 2205 lb. = 1.102 tons

(short ton, U.S.)

1 Ton (U.S.) = 907.18 kg = 2000 lb. = 0.907 tons

(metric)

NEAR Spacecraft can't do it, can you?

This may seem a bit strange, but so are some of the people associated with the NEAR project....

Asteroid 433 Eros, which the Near Earth Asteroid Rendezvous (NEAR) spacecraft will orbit starting in January 1999, was discovered on the night of August 13, 1898, at Berlin. The NEAR project people were hoping that NEAR itself could take a picture of Eros next month, 100 years after its discovery, for PR purposes. However, NEAR's camera is restricted to observing 90 +/- 40 degrees from the sun, and Eros will be 161 degrees from the sun in NEAR's sky. (Why? Power constraints. The camera optical axis is parallel to the plane of NEAR's solar panels, and the solar panels must be face-on to the sun to a tolerance of 40 degrees.)

I'm willing to bet that the NEAR project management would just *love* to have some CCD images of Eros taken on that night. I can't promise anybody any $$$, just your 15 minutes of fame if the pictures get the reception I expect. Any takers? Eros will be at magnitude 13.9, about 97 degrees from the sun in the evening sky, moving at about 1 arcmin/hr, and the moon will be nowhere near it. It will be near declination -27, so Northern Hemisphere observers will have to grab it ASAP after it gets dark.

Bill Owen, wmo@wansor.jpl.nasa.gov (member of NEAR navigation team)

Hollywood Educates the World?

The "Science" in 'Armageddon', Part 1

The Movie 'Armageddon' is out and making plenty of money. The story revolves around an asteroid the size of Texas headed for earth. As you might suspect, Hollywood did their usual fine job of portraying science on the big screen. The following is part 1 or a critique of the picture by Terry Burlison.

Well, I wasn't expecting much....

First, meteors do not travel in ravenous packs, as portrayed at the movie's start. A meteor shower consists of a few thousand BB sized (and smaller) grains spread over billions of cubic miles of space. They don't destroy cities, shuttles, and hard-working astronauts on EVA.

An asteroid "the size of Texas" would have been discovered decades ago. And there are FAR more than 8 telescopes "capable of seeing it." By the time it was 18 days from impact, it would be easily visible to the naked eye.

The asteroid belt is not jammed full of boulders "like billiard balls" waiting to be pulled toward earth by an interloper.

The shuttle "roll program" points the payload bay to earth during ascent. It does NOT put the shuttle into a Blue Angels climbing spiral. (And the External Tank does NOT separate with the solid boosters!)

THERE IS NO AIR IN SPACE! No roaring, whooshing sounds; no clouds drifting over asteroids; nor shuttles banking-to-turn. (Shuttles could fly sideways as easily as nose-first, and often do.)

Delete the ENTIRE scene aboard the "Russian space station." (I'm sure the Russians appreciate the cosmonaut's portrayal in the movie. Was Yakov Smirnov not available?)

Come back next month for part 2. . . .

Terry

Six String Software

http://www.sixstring.com

"Space…The final frontier"

And we've barely got our feet wet in it yet.

SOHO Spacecraft Contacted!

Contact has been re-established with the European Space Agency (ESA)/NASA Solar and Heliospheric Observatory (SOHO) spacecraft following six weeks of silence.

Signals sent yesterday through the NASA Deep Space Network (DSN) station at Canberra, Australia, were answered by SOHO at 6:51 p.m. EDT in the form of bursts of signal lasting from two to ten seconds. These signals were recorded both by the NASA DSN station and the ESA station at Perth, Australia. Contact is being maintained through the NASA DSN stations at Goldstone, CA; Canberra; and Madrid, Spain.

Although the signals are intermittent and do not contain any data information, they show that the spacecraft is still capable of receiving and responding to ground commands.

"This is an excellent sign," said Dr. Joe Gurman, NASA SOHO Project Scientist at the Goddard Space Flight Center, Greenbelt, MD. "It means the spacecraft still has a heartbeat and gives us added optimism that we may be able to restore SOHO to scientific operation. Our next step, already underway, is to continue the careful process of attempting to re-establish control of the spacecraft. We will be attempting, in the near future, to begin data transmissions in order to get an assessment of SOHO's condition."

More information, images and status reports from SOHO can be found on the Internet at:

http://sohowww.nascom.nasa.gov/

Contributed by:

David Stuart

MOC vs. MIC

A couple of issues back, in Sojourner, I mentioned the MOC imaging system. Well, here I would like to look a little closer at the MOC and maybe compare it to Planet-B's MIC (Mars Imaging Camera) imaging system.

MOC stands for Mars Observer Camera manufactured by Malin Space Science Systems. MOC in the simplest sense is a telescopic and a CCD camera system. The MOC is made up of three integrated optical subassemblies 1) Narrow Angle and 2) Wide Angle cameras 3) with common electronics designed to take high spatial resolution pictures of the surface of Mars and lower spatial resolution. It uses several advanced technologies, including the use of graphite/epoxy structural materials (the tube of the telescope) and 32-bit microprocessors for instance. The MOC is a cylinder 88-cm in length and about 40-cm in diameter. It uses the TIFF file format with one, hardware driven compression scheme, and two available software schemes. We have all seen the resulting images and they are very impressive.

In contrast, the Planet-B/Nozomia MIC camera captures images in JPEG with the lower image quality that the smaller file size entails. Still, for Japans' first launch to Mars the MIC should produce some very nice images. The MIC is approximately 92 mm x 150 mm x 235 mm in size. A comparison of both camera systems appears in Figure 1 (next page). MIC weighs about 2.5 kg and consumes about 14 W of power while imaging. The camera has 1 Mbyte onboard memory and will use standard JPEG image compression algorithm to compress images from 3 to 100 times. Like MOC, MIC will image Phobos and Deimos as well as Mars' weather and surface conditions.

Chris Vancil