firstlight€¦ · sirius is night's bright diamond in the sky, but canopus is truely the rare...

29° 39'N, 82° 21'W

FirstLight Newsletter of the

Alachua Astronomy Club February 1996

Have You Seen Canopus Tonight — H. L. Cohen Sirius is night's bright diamond in the sky,

but Canopus is truely the rare jewel of the night

Stargazers worth their weight in stars know Sirius — brightest star in the

night sky, jewel of the heavens, the firmament's "diamond in the sky." Located in Canis Major (The Big Dog), Sirius flickers and sparkles with rainbow colors. The brilliance and glow of the "dog star" have attracted attention since humans first turned eyes upward. Today, to those unfamiliar with night skies, its dazzling light appears unnatural, often stimulating thoughts of UFO's.

But, have you seen Canopus tonight?

Many of us know the names Procyon, Capella and Spica. To many, Pollux, Castor, and Arcturus are familiar. Others know Polaris directs us north and no star is closer to our solar system than Alpha Centauri. Betelgeuse and Rigel help out-line winter's Orion while Vega, Deneb and Altair form the summer triangle. Regulus, heart of Leo the Lion, heralds spring, and Aldebaran follows the seven Pleiades sisters into autumn. Many know reddish Antares rivals Mars during warm summer nights, and yellowish Capella is among the brightest stars of the heavens.


First place winners are always remembered, second place players often overlooked. Sirius, we know, is brightest looking of all. Who then follows? It is Canopus, of course. Usually forgotten, Canopus should dazzle us too. Most stars

Betelgeuse • Procyon

Canis Minor Orion

Sirius Canis Major,

Columba

Canopus Carina

FirstLight: Newsletter of the Alachua Astronomy Club

familiar to us appear four to sixteen times fainter than Sirius; only Canopus can compete with the Dog Star. Half as bright, we should all know this star.


In ancient Egypt, 15 miles east of Alexandria there once stood a seacoast city, site of a great temple honoring Serapis, god of the underworld and later worshiped in Greece and Rome. It bore the name Canopus. This old city is long gone but a glorious star still carries the splendor of these ancient empires. This second jewel of the night lies partly within an old constellation that, like the old northern Egyptian city, is no more. The sky once bore Argo Navis, The Ship Argo, and bearer of Jason, leader of the Argonauts, who went in quest of the Golden Fleece. Argo is now in pieces; the faint, obscure constellations of Puppis mark the stern, Vela the sails, and Carina (ka-n'na) the keel. At the end of the keel is the rudder, and there sits Canopus.

Canopus (ka-nop'us) is probably Latin, from Greek, kandpos, and perhaps of Egyptian origin. Its name is possibly first due to the Greek mathematician and astronomer, Eratosthenes, and was later used by the Greek astronomer, Hipparchus, who possibly designated this beautiful white star as the rudder. Today, Canopus also bears the designation Alpha Carinae meaning the star Alpha, belonging to the constellation Carina. This naming system is due to the Bavarian, J. Bayer, who published a list of over one thousand stars in 1603. Bayer gave conspicuous stars in each constellation Greek letters followed by the genitive form of the Latin constellation name to show possession.

So, Canopus is Carina's alpha, or Alpha Carinae (ka-iTne).

But have you seen Canopus tonight?

Probably not, for Canopus lies 35 degrees south (and 9 degrees west) of Sirius. Situated nearly 53 degrees south of the sky's celestial equator, this star is not visible from most of North America. From San Francisco, this star would vainly try to rise.From Atlanta, Canopus would never be more than two degrees above the horizon! From the continental USA, only those in the deep south, who know when and where to look, can view

FirstLight is the official, monthly publi-cation of the Alachua Astronomy Club (AAC), Gainesville, Florida. © 1996. All rights reserved. Send all written corres-pondence to:

P.O. Box 13744 Gainesville, FL 32604-1744 USA

Send all E-mail messages to [email protected]. Send address changes to AAC P.O. Box given above. For membership information, contact Ryan Loftus, AAC Treasurer, at 352-462-1227.

FirstLight Deadline: Submit articles for the club newsletter by the third Tuesday of each month. Send all material to Pamela Mydock, FirstLight Editor, P. O. Box 42, Lochloosa, Florida 32662. (Send all other correspondence to club's P.O. Box address above.) Submit articles printed in dark type; use a simple font (at least 14 pt. if possible). Double space between new paragraphs (do not indent). Better, E-mail articles in plain ASCII text to [email protected].

mailto:[email protected]



this heavenly star. In north Florida, Canopus rises halfway between southeast and south, barely reaches seven degrees (about one hand-width) above south before quickly descending toward the south southwest horizon. Above the horizon for less than six hours, most observers will barely have two hours to catch Canopus near its high point. Winter is best though the star is visible from about October to March.

Egypt and adjacent areas are nearly equally distant from the equator as north Florida. Thus, opportunities to view Canopus from the Mideast are similar to Florida. Imagine this star rising briefly above ancient, winter horizons giving its peoples but a brief glimpse of its dazzling beauty before disappearing from view. Some, perhaps, thought this star even more beautiful and mysterious than Sirius, itself. Judge for yourself. Go out and see Canopus tonight. Use the figure to help find Carina's alpha. The diagram shows Canopus near its high point at 9:00 p.m. (EST) on the night of February 15 for north Florida (specifically Gainesville). Look due south about one hand width high. Of course the horizon should be free of haze, trees and buildings. Haze, of course, will dim its apparent magnitude (-0.7).

The map will also work approximately for other dates. For each week later than February 15, make the time one-half hour earlier. The map approximates this scene for March 1 at 8:00 p.m. (But note that, by mid-March, sunset occurs at 6:30 p.m. so it becomes too light to see Canopus.)

Ancient peoples marveled that this bright star never rose high and probably wondered about its nature. Today

astronomers can say something about its properties. Canopus is relatively close, about 75 to 100 light years away. We know, too, that Canopus is receding from us at a typical stellar clip of 21 kilometers per second\

The spectrum of Canopus shows it belongs to a class of bright giants with moderate temperatures, or possibly to a group of low luminosity supergiants, stars that are in old age. (Its spectral class is variously given as A9 II or F0 Ib-II.) Estimates of its absolute magnitude also vary (-2.5 or brighter) but Canopus is probably about one thousand times more luminous than the Sun. Furthermore, stars like Canopus typically have surface temperatures of about 7,500 Kelvins, which makes Canopus about 30 percent hotter and at least 20 times larger in diameter than the Sun. Although masses of stars like Canopus are uncertain, Canopus may contain approximately three times more material than the Sun. However, because 6,000 Suns could fit inside, Canopus may have an average density 150 times less than water!

Find Canopus tonight. Sirius may be a diamond in the sky but Canopus is the rare jewel of the night. Like the Egyptians and Greeks who were awed by a bright, white star that never ascended the heavens, look upon Canopus knowing that whatever its nature, you are among the privileged who can gaze upon its face. Then remember the words of A.M. Klein (1909-1972) paraphrased here: "I am weak before the wind — before the sun I faint, I lose my strength. But I am utterly vanquished by a star — before these miracles I am nothing at all."

Make sure you see Canopus tonight. $


Upcoming Club Meetings and Events February Club Meeting

Date Tuesday, Febuary 13 Time 7:30 p.m. Place Auditorium, Doyle Conner

Building, 1911 SW 34th St. Speaker Dr. Francisco Reyes, Assistant Scientist in Astronomy, University of Florida, will review what is known about "The Jovian Decametric Radio Emission, " and will tell about current research at UF's Radio Observatory, including example sounds heard

during a typical Jupiter radio storm. Jupiter is one of the strongest low frequency radio sources in the sky, rivaled only by our Sun. The radio emission was discovered in 1955. It is the only planetary low frequency radio emission that can be detected by ground base stations. Detecting the strong Jovian decametic radio emission can be a suitable project for amateur radio astronomers.

March Club Meeting

Date Tuesday, March 12 Time 7:30 p.m. Place Auditorium, Doyle Conner

Building, 1911 SW 34th St Speaker Mr. T. J. Vaccaro, Department of Astronomy, University of of Florida, will present a talk about the star V471 Tauri. His

topic is titled: "One Dwarf, Two Dwarf, Red Dwarf, Wliite Dwarf." He will present observation data and computer modeling ideas about the bright emissive region on a red dward star as a result of flourescence from a companion white dwarf star.

Star Parties

Sfar parties begin at sunset and meet at Bob Jacobs' unless otherwise stated. Address 9617 NW 143 St. (HWY. 241) —1.7 mi. North of Millhopper Rd. (HWY. 232). Look for Hurricane Harbor sign just past brick mailbox on

right side of road. Go a few hundred feet up paved driveway to Bob's house. (Do not continue up onto dirt road)

Feb. 10 (Sat. Night); rain date Feb. 17. Mar. 16 (Sat. Night); rain date Mar. 23.

No date set for April yet; on Thursday , Apr. 4 there is a partial lunar eclipse.


January Executive Council (Tuesday, 6:30 P.M., January 9th at Doyle Conner Building)

— Mark Cowan

Brief meeting before regular monthly meeting; two items discussed. First, do we want to donate the 5-inch refractor donated by Jan Sugalski as a Science Fair prize? Second, President John Brandorff has a letter

from the Science Fair asking about our prizes this year. Both items discussed further, during the regular meeting.

Minutes: Jan. Executive Council (Tuesday, 7:30 P.M., January 9th at Doyle Conner Building)

— Mark Cowan

Treasurer's Report by Ryan Loftus: S293 dollars with five members paid for 1996. Don and Ryan Loftus to open an account in Don's name at the Campus Credit Union; President John Brandorff will be joint owner on record.

Science Fair Prizes: It was decided that the five-inch refractor would be kept as a club scope. Science Fair prizes will include AAC membership for all astronomy exhibitors. The Senior winner will be awarded a one-year subscription to Sky and Telescope and the Junior winner will be awarded a one-year subscription to Astronomy.

AAC Club Scopes: It was decided that Bruno Pancorbo, keep a record of club scope loans to members.

Sidewalk Astronomy: Don Loftus presented the idea to promote a membership drive.

Money Ideas: John Brandorff wants club

members to think about ideas for raising money for the club, such as club t-shirts, possibly for sale at the Spring Arts Festival.

Texas Star Party: John, Bruno, and Dale are planning a road trip to Texas; wanna go along? It's the week of May 12th.

Star Party Requests: TheAlachua Branch of the county library has requested a star party, tentatively on Monday, March 11. Glenn Springs Elementary would like any date in February. Volunteers?

Mirror Kit: Curtis Loftus brought in a six-inch telescope mirror kit that he plans to build.

January Program: John Brandorff introduced Mark Cowan, speaking about January observation of Messier objects and three asteroids. Mark presented color slides of what is available for viewing and some sky maps generated by SkyMap, version 2.2. 0

The AAC Web address is now h t t p : / / w w w . a s t r o . u f l . e d u / ~ c o h e n / a a c

http://www.astro.ufl.edu/~cohen/aac


February Executive Council — PamMydock

Attending: John Brandorff, Chuck Broward, Howard Cohen, Mark Cowan, Don Godman, Don Loftus, Ryan Loftus, Pam Mydock,

Bruno Pancorbo, Duane Sandene

Location: Shoney's on NW 13th St, Gainesville, 6:30 P.M.

Mark announced that he had to temporarily resign his duties as secretary, to attend to an illness in the family. Pam volunteered to take over his duties, until he can return.

Ryan and Don found an advertisement for some reasonably priced checks with three different astronomy scenes. Everyone agreed we should buy 150 of them instead of the standard issue available from the credit union. They also have carbonless copies attached.

Don also showed us the new club stationery , featuring Howard's new logo design and the P.O. Box address.

A few suggestions were made for the program schedule for the remainder of 1996. Howard will see if Rosemary Hill observatory could be made available on a Tuesday night for a regular club meeting. It was decided that October's meeting should focus on "Buying and Using a Beginner's Telescope. " We need a club member to volunteer to organize and present this topic. It should be very popular with grandparents and the

general public, just before the holidays.

Howard presented a new draft of the club brochure. Chuck will check prices for offset printing in quantity. We plan on using a large quantify for our membership drives for the coming year. Besides the two evenings at Kanapaha Botanical Gardens, it was decided to carefully plan and advertise two other public "Sidewalk Star Parties, " possibly at the Oaks Mall or at one of the public schools or even at a supermarket parking lot. We will be discussing this topic further at the next meeting. So be ready with your input.

John feels that we need to be more focused with our public exposures and gear them towards generating new members. Bruno suggested that the Kanapaha evenings could be better organized in favor of recruiting. We will have a well-lighted table, manned with people to hand out our brochures and talk to the public to encourage membership. It was suggested that the telescopes be arranged in more of a circle instead of all in a row.

We need to manage the crowd, rather than be at their mercy. We will need volunteers to make banners and man the


recruiting table. We also need some people with very simple low power telescopes and binoculars, so beginners do not feel intimidated by magnification or money.

$50, payable with the first order. John will try to bring some samples to the meeting on Tuesday. Baseball caps would be $7 and the shirts range in price up to about $20.

Don Godman, our contact man for the last Moonlight Walk, will talk to the people at Kanapaha to see if they will include our logo in their advertisements. This would be a way to get our club free advertising.

John talked to Central Monogramming in Gainesville about getting our new logo on shirts and hats. The initial set-up fee is

Chuck and John have volunteered to judge the Alachua County Science Fair for Astronomy, at the end of the month.

Please remember to bring your dues with you to the general meeting on February 13th, at 7:30 P.M.

North Central Florida's Amateur Astronomy Club

AAC meets every second Tuesday of each month, at 7,30 p.m., in the Doyle Conner Building, 1911 S.W. 34th Street (at S.W. 20th Avenue), Gainesville, Alachua County, Florida, USA; General public and beginning stargazers are invited to all meetings, star parties and club events. No equipment needed. Call an officer (area code 352) for more info or e-mail [email protected].

President John Brandorff Gainesville (375-1043)

Vice-President Howard L. Cohen Gainesville (376-5833)

Treasurer Ryan Loftus Alachua (462-1227)

Secretary Mark Cowan Gainesville (375-2564)

Star Parties

FirstLight Editor

Publisher

Bruno Pancorbo Gainesville (373-0279)

Pamela Mydock Lochloosa (481-5238)

Chuck Broward Melrose (475-1014)

World Wide Web Home Page at URL http://www.asfro.ufl.edu/~cohen/aac


http://www.asfro.ufl.edu/~cohen/aac

February Astro Calendar (Times EST) d h m

Thu 1 07:00 Julian Date 2,450,115.0 (UT= Feb 1 12:00)

Fri 2 18:30 Venus (mag.-4.1) 1.2° NW of Saturn (mag. = +1.2)

Sun 4 10:58 Full Moon Sun 11 16 Mercury at greatest elongation W

(26°) 21 Earth passes to South side of

Saturn's ring-plane (south side of planet now faces Earth until Sept. 2009) Last Quarter Moon New Moon Mars at perihelion Venus only 3.3° N of Moon (Look about 20 minutes after sunset)

Mon 26 00:52 First Quarter Moon

Mon Sun Tue Thu

12 18 20 22

03:37 18:30

18:45

firstlight€¦ · sirius is night's bright diamond in the sky, but canopus is truely the rare...

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