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TVS director Gert Gottschalk captured these four images of Mercury transiting the Sun on November 15, 1999. Details of his photography are as noted below.
Instrumentation: 80mm APO refractor, f8 with two-inch 2X Barlow.
Film: Kodak Gold 200, developed and scanned, then processed on PCs.
Location: San Jose, CA, from his company's parking lot.
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For your consideration
The following items have been discussed at various planning meetings. We offer a bit more detail here to invite your consideration and discussion.
The great solar telescope debate
The board vacillates on the subject of adding a loaner telescope equipped for solar viewing. On the one hand, a few members have expressed interest in renting a scope that they could use for daytime observing. On the other hand, solar observing is inherently risky and can permanently blind the unskilled user.
At the December potluck, Dave Anderson will lead a club-wide forum on the pros and cons of adding a solar telescope to our loaner program. The board has heard much emotionally charged testimony. We are now asking experienced daytime observers to share their expertise with the club. Please come to the December meeting prepared to talk about this subject.
Teaching our own members
To more readily help one another become better observers, the board has approved an order of 20 copies of the Observer's Handbook 2000. Copies are available at the discounted price of $13 each. Be prepared with exact change, or be willing to write a check that is separate from dues and subscriptions.
Trick or treat or telescopes
Member Jim Brown reports outstanding success on Halloween, when he combined Hersheys with Herschels to offer neighborhood children a little sidewalk astronomy. Do we have any interest in formalizing a TVS "Scopes and Skittles" program for 2000?
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Geminids shower due
December 13-14
Information courtesy of NASA Star Trails
The first Geminid meteors suddenly appeared in the mid-1800's. Those early showers were unimpressive, boasting a mere 10-20 shooting stars per hour. Since then, however, the Geminids shower has grown in intensity until today it is one of the most spectacular annual showers. In 1996, the last time the Geminids appeared in a dark Moon-less sky, observers saw as many as 110 per hour.
After the discovery of the Geminids in 1862, astronomers began searching for the parent comet. Most meteor showers result from debris that that boils off a comet's nucleus when it passes close to the Sun. This debris orbits the sun along with the comet, forming a thin, elongated stream of meteoroids that become shooting stars when they hit Earth's atmosphere.
Years of searching proved to no avail until finally, in 1983, NASA's Infrared Astronomical Satellite discovered a curious object moving in the same orbit as the Geminid meteoroid stream. The orbital match was so good that it had to be the source of the debris, but to the surprise of many it wasn't a comet. The source of the Geminids was apparently a rocky asteroid.
3200 Phaethon, as the asteroid is now known, is in a highly elliptical 1.4-year orbit that brings it within 0.15 AU (astronomical units) of the Sun. It made its closest recent approach to Earth in December 1997 when it passed within 0.31 AU of our planet.
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