Stockton Astronomical Society
Valley Skies - December 2003 Issue
At the November 13 general meeting members elected the following officers:
| President: | Jerry Hyatt |
| VP/Program Director | [open] |
| Secretary | Christie Abbott |
| Treasurer: | Jerry Hyatt |
| Newsletter Editor: | Trevor Atkinson |
| Member-at-Large: | Kay Gorman |
| Member-at-Large: | Richard Roach |
Since the election, Jerry reviewed the incorporation papers and learned that California law does not allow the president to also serve as treasurer or secretary. By mutual agreement, Eric Reichenbach has agreed to continue as president for another year, and Jerry will continue as Treasurer - subject to approval by members attending the December meeting.
...Trevor Atkinson
January Dinner Speaker: Dr. Kent Cullers
Kent Cullers' career is an amazing story.
Blind since birth, he earned his Ph.D. from the University of California at Berkeley in 1980, becoming the first totally blind physicist in the world. He immediately joined NASA's Ames Research Center, and later, the SETI Institute, as a founding member. He designed detection algorithms for weak signals, currently used for SETI; for finding early signs of breast cancer in diagnostic mammograms; and for direct photometric detection of Earth-sized planets.
In addition to his duties as Director of Research and Development at the SETI Institute, he is a popular guest lecturer, travelling extentively to about 100 speaking engagements a year.
A National Merit Scholar, Cullers has been the recipient of many honors and awards, including NASA's Exceptional Engineering Achievement medal and the Federal Employee of the Year award.
He's on the Board of Directors of the Sensory Access Foundation and the Peninsula Center for the Blind and Visually Impaired. Cullers earned his first amateur radio operator license at age eleven, in 1961, and he's still listening for that distant transmission.
SETI, the radio search for extraterrestrial intelligence, searches the heavens for signs of technology. The expectation is that radio searches will expand rapidly, based on the explosion in computer technology. Within the next century, we may completely search our galaxy for signals like those now transmitted from Earth.
Come listen to the sounds of the cosmos and learn how computers analyze data to differentiate the traces of technology from natural signals in the sky.
In the complete absence of a faculty that most of us consider vital, but nevertheless take for granted, Kent Cullers has accomplished more than most. It will be an honor and privilege to share the evening with him on January 8.
(See page 9 of the December newsletter for the dinner reservation coupon)
Stardust
by Patrick L. Barry and Dr. Tony Phillips
Philosophers have long sought to "see a world in a grain of sand," as William Blake famously put it. Now scientists are attempting to see the solar system in a grain of dust-comet dust, that is.
If successful, NASA's Stardust probe will be the first ever to carry matter from a comet back to Earth for examination by scientists. It would also be the first time that any material has been deliberately returned to Earth from beyond the orbit of the Moon.
And one wouldn't merely wax poetic to say that in those tiny grains of comet dust, one could find clues to the origin of our world and perhaps to the beginning of life itself.
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NASA's Stardust mission will capture dust from comet Wild 2 and bring them back to Earth for study. |
Comets are like frozen time capsules from the time when our solar system formed. Drifting in the cold outer solar system for billions of years, these asteroid-sized "dirty snowballs" have undergone little change relative to the more dynamic planets. Looking at comets is a bit like studying the bowl of leftover batter to understand how a wedding cake came to be.
Indeed, evidence suggests that comets may have played a role in the emergence of life on our planet. The steady bombardment of the young Earth by icy comets over millions of years could have brought the water that made our brown planet blue. And comets contain complex carbon compounds that might be the building blocks for life.
Launched in 1999, Stardust will rendezvous with comet Wild 2 (pronounced "Vilt" after its Swiss discoverer) on January 2, 2004. As it passes through the cloud of gas and dust escaping from the comet, Stardust will use a material called aerogel to capture grains from the comet as they zip by at 13,000 mph. Aerogel is a foam-like solid so tenuous that it's hardly even there: 99 percent of its volume is just air. The ethereal lightness of aerogel minimizes damage to the grains as they're caught.
Wild 2 orbited the sun beyond Jupiter until 1974, when it was nudged by Jupiter's gravity into a Sun-approaching orbit-within reach of probes from Earth. Since then the comet has passed by the Sun only five times, so its ice and dust ought to be relatively unaltered by solar radiation. Some of this pristine "stuff" will be onboard Stardust when it returns to Earth in 2006, little dusty clues to life's big mysteries.
To learn more about Stardust, see the mission website at stardust.jpl.nasa.gov.
Kids can play a fun trivia game about comets at spaceplace.nasa.gov/stardust.
This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.
Solar maximum is years past, yet the sun has been remarkably active lately. Is the sunspot cycle broken?
November 12,2003: Imagine you're in California. It's July, the middle of summer. The sun rises early; bright rays warm the ground. It's a great day to be outside. Then, suddenly, it begins to snow - not just a little flurry, but a swirling blizzard that doesn't stop for two weeks. That's what forecasters call unseasonal weather. It sounds incredible, but "something like that just happened on the sun," says David Hathaway, a solar physicist at NASA's Marshall Space Flight Center. Only a few weeks ago solar activity was low. The face of the sun was nearly blank - "very few sunspots," says Hathaway - and space weather near Earth was mild. "Mild is just what we expect at this point in the 11-year solar cycle," he explains. "The most recent maximum was in 2001, and solar activity has been declining ever since." Then, suddenly, in late October the sun began to behave strangely. Three giant sunspots appeared, each one larger than the planet Jupiter. In California, where smoke from wildfires dimmed the sun enough to look straight at it, casual skywatchers were startled by the huge blotches on the sun. One of them, named "sunspot 486," was the biggest in 13 years.
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Astrophotographer Bob Sandy of Virginia took this picture of giant sunspot 486 emerging over the sun's limb on Oct. 23, 2003. It is preceded by another giant spot, numbered 484. |
"In 1989 a flare about half that strong caused a widespread power blackout in Quebec," recalls Hathaway. Last week's blast was aimed away from Earth, so its effects on our planet were slight - a bit of good luck. All this happened two years after solar maximum, which raises a question: is something wrong with the solar cycle? Is the sun going haywire? "Nothing's wrong," reassures Hathaway. The sun isn't about to explode, nor is the sunspot cycle broken. "These latest sunspots were whoppers," he allows, "but sunspot counts averaged over many weeks are still declining as predicted. We're still on course for a solar minimum in 2006." Indeed, it's possible that what we've just experienced is a normal part of the solar cycle, speculates Hathaway. "There's a curious tendency for the biggest flares to occur after solar maximum - on the downslope toward solar minimum. This has happened during two of the last three solar cycles." The plot below illustrates his point.
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Using data archived by NOAA's Space Environment Center, Francis Reddy created this plot of sunspot number and X-class solar flares during the last three solar cycles. |
Consider the year 1984, says Hathaway. Sunspot counts were plunging, and the sun was rapidly approaching the 1985-86 solar minimum. Suddenly a giant sunspot appeared, Jupiter-sized like sunspot 486, and unleashed two dozen M-flares and three X-flares, including a remarkable flare registering X13. People then probably wondered too if the solar cycle was broken. "It's hard to be sure what's normal and what's not," notes Hathaway. "Astronomers have been observing x-rays from the sun for only 35 years - or three solar cycles. We can't draw good statistical conclusions from so few data."
One thing is certain though - flurries of solar activity can happen at any time. The next time, says Hathaway, could be just a week or so away. Sunspot 486 and its companions are on the far side of the sun now, carried around by the sun's 27-day rotation. "We suspect they're still active," says Hathaway, because the Solar and Heliospheric Observatory - a sun-watching satellite - has photographed clouds of gas being thrown over the sun's limb by unseen explosions. Unless these sunspots dissipate, which could happen, they will reappear on the Earth-facing side of the sun beginning as early as Nov.14th. And then...? No one knows. "We might get some more unseasonal space weather," says Hathaway. But this time he won't be surprised.
From Science@NASA website: http://science.nasa.gov
The Science Directorate at NASA's Marshall Space Flight Center sponsors the Science@NASA web sites. The mission of Science@NASA is to help the public understand how exciting NASA research is and to help NASA scientists fulfill their outreach responsibilities.
MORRISON PLANETARIUM MARKS END OF AN ERA
by J. M. Ryan
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The black star projector, lit in primary colors by gleaming spotlights, sits ten feet above the audience, amidst the 65-foot star theatre, vaulted by a dome of white perforated aluminum higher than a four-story building. The great instrument is one of a kind; unique in the world, incredibly durable and, in the realism of its projected sky, still among the best ever.
The salon-like theatre, warm and welcoming, features comfortable chairs, subdued lighting, and wafting music. The plaques on the walls, the glass case with archival displays, the remnant of the original console with its red and black toggle switches, and the spotlighted bust of Alexander Morrison, convey a sense of history. Metal cutouts, artistically shaped as buildings, bridges, and landmarks form a familiar San Francisco skyline-in-silhouette around the periphery, where the arching dome meets the circular wall.
In the gallery beyond the western wall of the theatre, the gleaming brass teardrop that is the Foucault Pendulum swings endlessly to and fro across a fenced circular pit, demonstrating the relentless turning of the Earth. Entranced visitors stand or lean for long minutes contemplating the ceaseless motion as they anticipate the periodic toppling of the vertical pegs, each delicately stood on end at its respective mark.
Unfortunately, this exquisite venue and the remarkable machine at its heart will serve the public only through December 31st of this year. Anyone wishing to visit the historic planetarium and its outstanding artifacts, or to witness the fine, original shows still produced at Morrison, a rarity in today's world of standardized product, has just until year's end to do so.
The Academy, in process of creating a modern facility for the 21st century, will soon relocate elements of its museum and aquarium to 875 Howard Street, while it demolishes, then rebuilds its 75-year-old home in Golden Gate Park. Morrison Planetarium, too, will be rebuilt, with a new projector, in the modern style of planetaria today. The new complex, though, will not open to the public until mid-2008. In the interim, Morrison will continue public outreach activities using inflatable domes, and offer lectures in other venues.
But there's been no word concerning the preservation, display, or transfer of the projector and the other historic fixtures. Architectural models of the planned new facility show no space allocation to display these historic artifacts. There's been no public comment, but the Academy is seeking a home where the projector, at least, can be operated or displayed. It might appreciate knowing the thoughts and preferences of members, patrons, and interested advocates.
Citizens of the San Francisco Bay region share a vested interest in the outcome. The planetarium was a landmark exercise in the power of citizen involvement and initiative.
Schoolchildren famously donated their pennies to help make it a reality. And it has, for decades, been a favorite field trip for school classes around the Bay, and across the state.
For those who've admired or even loved Morrison Planetarium, time is short and opportunity fleeting. Those interested in enjoying the unique ambience of the star theatre should plan to visit before final shutdown on December 31st. The planetarium will present shows every day except Thanksgiving and Christmas.
The regular show schedule terminates on Sunday, December 28th. From Monday, December 29th through Wednesday, the 31st, the Academy and Planetarium will offer a three-day open house, waiving admission fees. Morrison will feature the live program "The Sky Tonight" eleven times a day, every hour from 10 a.m. to 8 p.m. The timing will allow the opportunity for questions and picture-taking. The Wednesday show at 8 p.m. will be the last.
Mr. Ryan is one of those for whom a visit to Morrison Planetarium as a young child in 1953 kindled an abiding interest in astronomy. He has been a lifelong amateur astronomer and astronomy educator, an aerospace researcher and engineer. He has also twice worked for Morrison.
Copyright © 2003 by Stockton Astronomical Society
Last Updated: 12/8/2003
http://astro.sci.uop.edu/~sas/Newsletter/VS0312.html