Explorit Science Center

ASTRONOMY CLUB NEWSLETTER

JANUARY 1996 Issue

MAKING AND USING A PLANISPHERE

AT EXPLORIT

ON SATURDAY JANUARY 20, AT 7:30 P.M.

COME TO OUR NEXT MEETING

at 7:30 p.m. on January 20 at Explorit.
The evening's topic will be "Making and Using a Planisphere." This is the second in our series on constructing astronomical instruments. Beginners will find this session very useful in getting acquainted with the constellations and visualizing how they move. A planisphere is a helpful instrument, which every amateur star gazer should have. It is like a simple map to heavens for any hour of any month of the year. Do you already have a planisphere? Please bring it to the meeting to share. (Also, please bring your astrolabes, see below) The planispheres we make will be constructed of paper and show only the major constellations, but they are great introductions to the starry sky and how it changes. Here is a question to think about for our next meeting: Which astronomical objects cannot be shown on a planisphere?

MAKING AN ASTROLABE

The club met on December 9 to discuss and make astrolabes. The astrolabe was the forerunner of the modern navigational sextant, and measures angles between the horizon and objects in the sky. They can also be used to measure angular distances between objects. We built ours from paper, a plastic soda straw, string and a metal washer. Thanks to Tim Feldman who managed to find replacements for the soda straws I forgot to bring! The weather was too overcast to try out our astrolabes, perhaps we will have better luck January 20th!

WHAT'S UP IN JANUARY?

Winter is a wonderful time to begin to learn where the constellations are and how to find your way around the sky. Why? Because it gets dark quite early, and the constellations in the winter are composed of bright stars in some easily recognized distinctive patterns. Weather permitting, we will be pointing out these constellations at our meeting in January.

PROMINENT CONSTELLATIONS visible around 9:00 p.m. are:
  1. in the West: Pegasus (Flying Horse);
  2. overhead: Cassiopeia (the Queen); Perseus (the Hero); Taurus (the Bull) and Auriga (Charioteer);
  3. in the South: Orion (Hunter) and
  4. in the East Gemini (the Twins) and Leo (Lion).

JANUARY PLANETS

SUNSETS (around 5:15) Around the 18th, Mercury sinks below the horizon, leaving the twilight evening sky to Venus and Mars. On the 21st look for the young crescent Moon between Venus and Saturn; and on the 22nd the Moon is near Venus, and on the 23rd it is near Saturn.

EVENINGS Saturn is low in the southern sky in the evening and many telescopes will be observing it in its "ringless" state (which will continue into February).

MORNINGS (around 7:20) Jupiter is the brightest "morning star" at sunrise, and Mercury begins to move into the sunrise after mid-month. Around 7:00 a.m. January 18th the waning crescent Moon will make a nice picture with Jupiter in the southeast.

ASTRONOMY CLUB OUTREACH

On the evening of Tuesday, December 19th, as part of Explorit's frontiers of science series of presentations, club member Tim Feldman showed how astronomers have been able to calculate what the ancient skies may have looked like over Bethlehem around the time of the nativity of Jesus. The "Star of Bethlehem" may have been a conjunction of planets, as demonstrated by sophisticated computer models. Tim's use of a computer projection screen for the presenation was particularly effective in conveying the movements of the heavens to the audience. Thank you, Tim!

FUTURE MEETING TOPICS

What topics would you like to include in future meetings? During 1995 we discussed: how to fight light pollution, Egypt's pyramids and Orion, stellar birth and evolution, the Moon past and present, high tech comes to amateur astronomy, and we considered the case for extraterrestrials. I am sure that we will have information on Galileo (the space probe), once the Federal government furlough is over and we can get the data from NASA, but what other topics would YOU like to see on our agenda?

The Astronomy Club is hosted by Dennis Smith with the assistance of Tim Feldman and other eager astronomy buffs. The club is for everyone - adults, children, knowledgeable or ignorant. Come to listen, look and learn, or to share your expertise or experience.


Now you can, if you wish, take an exciting side trip to some other sites for a session of:
Astronomical Browsing!
or go
Back to our Newsletter Index
Send feedback to
Explorit Science Center
P.O. Box 1288, Davis, CA 95617, USA
Phone: (530)756-0191     Fax: (530)756-1227
Page last updated: July 23, 2005