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March 2005 Observatory (619) 766-9118 a Non-Profit Educational Association P.O San Diego Astronomy Association Celebrating Over 40 Years of Astronomical Outreach Office (619) 645-8940 March 2005 Observatory (619) 766-9118 http://www.sdaa.org A Non-Profit Educational Association P.O. Box 23215, San Diego, CA 92193-3215 Combinations Changing at Tierra Del Sol! The combinations for the front gates, pedestrian gate, SDAA Business Meeting power and pump will change on March 13th, the day Next meeting will be held at: SKF Condition Monitoring after the Messier Marathon at Tierra Del Sol. The 5271 Viewridge Court new combination appears on the mailing label of this San Diego, CA 92123 March 8th at 7:00pm newsletter. Volunteers Needed For Beginner Program Next Program Meeting There is a move to start a new Beginner Program within the club. The program would teach people new to astronomy about what’s up there to view, how to find the objects, March 16th 7:00 pm and about the mounts and telescopes to view those objects. We need volunteers to Mission Trails Regional Park make this program happen. If you are interested in helping out with this project and Visitor and Interpretive Center could donate an hour per month of your time, contact Bob Austin at 1 Father Junipero Serra Trail [email protected] or (760) 787-1174 Need to pay your membership dues? Renew your subscription? There are 2 ways. • The easiest way is to go to http://www.sdaa.org and click on the CONTENTS Membership tab on the left. Then scroll down to the bottom and click March 2005 Vol XLI, Issue 03 Renew. This will take you to PayPal. Once you have completed the Published Monthly by the transaction, click the Continue button at the bottom of the screen so San Diego Astronomy Association the Treasurer gets notified of the payment. You will be taken back to 75¢ /$8.00 year the SDAA website. • Incorporated in California in 1963 You can also pay by check made to SDAA (not to a publisher) and mail it to P.O. Box 23215 San Diego, CA 92193-3215. If you are Gate Combinations Changing......................1 renewing a subscription, please include your renewal notice and any Astronomy 101............................................2 envelope the publisher sent you. Calander .....................................................4 Current rates are: • Camp with the Stars .....................................5 Basic Membership $30.00 • Board Minutes ..............................................6 Contributing Membership $50.00 • Treasurer’s Report.......................................6 Astronomy Magazine $29.00 • ASIG ..............................................................7 Sky & Telescope Magazine $32.95 • Sky Watch.......................................................8 Sky Watch $ 5.99 • The Urban Astronomer.............................9 Odyssey Magazine $25.46 • Astronomy Crossword..............................10 Private Pad Lease $35.00 NASA Space Place.....................................12 Please remember, Private Pad Lease fees are due at the same time membership Editors Note................................................13 fees are due. The Back Page...........................................14 SanSan DiegoDiego AstronomyAstronomy AssociationAssociation By Scott Baker Just a little off the top This month’s constellation is Coma Berenices (the hair of Berenices). There are several tales that describe how this constellation came to be, one involving the tail of Leo, but the most famous tale is about a beautiful woman, Berenices, the Queen of Egypt. Berenices, a beautiful woman with extraordinary hair, was married to Ptolemy III, the King of Egypt. Ptolemy had been waging a war, for some time, with the Assyrians, who had killed his sister. When the war was not as ancient as the story would lead as bright. Its companion, almost the nearing its conclusion, Ptolemy was you to believe, but one created and same size and color, circles the star so needed for one last battle. Berenices cataloged by Tycho Brahe (1546- closely, that its separation is measured pleaded with him not to go, but it was 1601). in hundredths of an arc second. If you to no avail, he needed to finish the war. can split this double, at .05 arc Fearing for Ptolemy’s life, Berenices The constellation of Coma Berenices seconds, you better check for a hair prayed to the gods for his safe return, is really unremarkable as far as across your eyepiece! A much more telling them that she would sacrifice prominent stars, containing only a pleasing double, and easy in small her beautiful hair for his safety. The handful of 4th magnitude stars within scopes, is 24 Comae. Much like gods agreed and Ptolemy, victorious its boundaries. However, small and Albireo in Cygnus, 24 Comae is an over the Assyrians, returned home insignificant as it is, it contains no less orange giant of 5th magnitude, which safely. Hearing of his safe return, than eight Messier objects and a HUGE contrasts beautifully with the blue- Berenices cut off her long beautiful number NGC of objects. Within its white 7th magnitude companion. hair and placed it in the temple as borders is a portion of the area known promised. Ptolemy, seeing his wife’s as the Coma-Virgo Supercluster of For open clusters, Coma Berenices has new “do,” was outraged and went to galaxies and galaxies are what you’ll an excellent example, the “Coma Star the temple to retrieve her hair. Upon find here. There are over 2000 Cluster.” Best seen with binoculars, the arriving at the temple he found that her galaxies in the Coma Virgo Superclus- cluster, containing eighty or so stars, hair was missing which only enraged ter, which also encompasses our own covers over five degrees of sky. The him more. Fearing for Berenices life, “Local Group.” cluster was once known as the fuzzy the Greek astronomer Conon of ball of hair at the end of Leo’s tail, until Samos, who was in Egypt at the time, Before we delve into the galaxies it’s the constellations were redrawn by intervened. He told Ptolemy that the famous for, let’s take a look at a few Tycho Brahe, now the cluster forms the Goddess Aphrodite had come and taken other objects first. knot of Berenices hair. the hair into the heavens, where it shown for all to see, and pointed out For double stars, you can try to split, When you were trying to split Diadem, the constellation to Ptolemy. This but I’m sure you won’t succeed, Alpha you may have caught M53 in your field seemed to appease Ptolemy and all Comae. Called Diadem, Alpha Comae, of view. M53, a fine globular cluster, lived happily until the queen’s death in a star much like our own sun, is 62 is the brightest, at magnitude 7.7, of 223BC. Despite the nice tale, the light years away but shines three times the eight Messier objects in Coma. constellation of Coma Berenices is Astro 101 continued on page 3 Page 2 SAN DIEGO ASTRONOMY ASSOCIATION NEWS AND NOTES, MARCH 2005 San Diego Astronomy Association Lying some 65,000 ly away, it takes a Other ID: HIP 61418, SAO 100160 Other ID: NGC4382 larger scope to resolve the mass of stars Magnitude: 5.03 into individual points, but still worth a Equatorial 2000: RA: 12h 35m Object name: NGC 4394 look in any size instrument. A little more 07.758s Dec: +18°22’37.528" Magnitude: 10.9 difficult at 9th magnitude, 1-degree to Flamsteed-Bayer: 24 Comae Berenices Equatorial 2000: RA: 12h 25m 56s Dec: the southwest lays NGC 5053, another Magnitude B: 6.45 +18°12’51" nice, slightly irregular, globular. Magnitude V: 5.11 Size: 3.4 x 3.2 Angular separation: 08°18’11.101" Object type: Spiral Galaxy Now let’s take a look at what Coma is Dreyer description : Pretty bright, little known for, galaxies! We’ll start with Object name: Coma Star Cluster extended, brighter middle. M64, the “Black Eye” Galaxy. It gets its Other ID: SAC Mel 111 nick name of “Black Eye” from the large Equatorial 2000: RA: 12h 25m 00s Dec: Object name: M 88 obscuring dust cloud at the core of the +26°00’00" Magnitude: 9.4 galaxy, giving it the impression of Size: 275.0 x 275.0 Equatorial 2000: RA: 12h 31m 59s Dec: having a “black eye.” The dust cloud is Object type: Open Cluster +14°25’11" only visible with large scopes under Notes: Coma Berenices star cluster Size: 6.8 x 3.7 ideal conditions; however, the galaxy is Number of Stars: 80 Object type: Spiral Galaxy still a nice compact spiral in smaller Other ID: NGC4501 scopes. M85 and M88 are both fairly Object name: M 53 bright spiral galaxies, with M88 showing Magnitude: 7.7 Object name: M 91 multiple spiral arms under good Equatorial 2000: RA: 13h 12m 55s Dec: Magnitude: 10.1 conditions. While looking at M85, try +18°10’11" Equatorial 2000: RA: 12h 35m 26s Dec: and glimpse the fainter NGC4394 in the Size: 13.0 x 13.0 +14°29’47" same field. M91, M98, M99 and M100 Object type: Globular Cluster Size: 5.2 x 4.2 are all nice galaxies of varying sizes and Other ID: NGC4548 types which deserve more space than Object name: NGC 5053 we have in this newsletter. With so Magnitude: 9.0 Object name: M 98 many galaxies in this area, you wonder Equatorial 2000: RA: 13h 16m 27s Dec: Magnitude: 10.1 why Messier, picked these to put on his +17°41’55" Equatorial 2000: RA: 12h 13m 48s Dec: list, when it could have been so easy to Size: 10.0 x 10.0 +14°53’58" create his list of 110 objects in this area Object type: Globular Cluster Size: 9.8 x 2.8 of the sky alone. Dreyer description : Cluster, very faint, Object type: Spiral Galaxy pretty large, irregularly round, very Other ID: NGC4192 Coma Berenices has a wealth of objects, gradually brighter middle, stars of especially on its southern border with magnitude 15.
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