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Home My WebLink AboutThe Lucknow Sentinel, 2015-12-30, Page 9Wednesday, December 30, 2015 • Lucknow Sentinel 9 Sirius Astronomy during the winter months John Hlynialuk Bluewater Astronomical Society I learned long ago about the trick question in astron- omy: "What is the brightest star in the sky?" My answer, for a while any- way, was "Sirius" but this is the correct answer to a different question: "What is the brightest star in the skyvisible at night?" As for the first question, the brightest star in our sky is, of course, "Sol" or "our sun" -which a student gleefully pointed out to me after one class. At least she didn't embar- rass me in front of my students, for which I was thankful. The brightest nighttime star, Sirius, is now visible for the entire night as it follows Orion across our winter sky. Have a look for this famous star in the SE after sunset Ifyou followthe Belt Stars of Orion downwards you can't miss it Even near the horizon, its brightness makes it unmistakable. In the same part of the sky are another half dozen "sparklers; - Procyon, Betelgeuse, Castor, Pollux and Rigel, -but the brightest jewel of our winter sky will always be Sirius. And as such it has a spe- cial place in the history of civili- zations in both hemispheres. The alpha star of the constel- lation Canis Major, Sirius is often shown as a jewel in the collar of the Big Dog. It is visi- ble from a large portion of the Earth's surface during the northern winter (southern hemisphere summer). Though itis highest in the winter sky in North America, in the eastem hemisphere it was recognized as a herald of the summer sea- son and astronomers noted the date when it was first seen just before sunrise, the helical rising of Sirius. For Egyptians, it marked the return of floods on the Nile. For Greeks, the star's name trans- lates into "scorcher" and it ushered in the "dog days" of summer, an expression still used in the Americas. For the Polynesians in the southern hemisphere, the star was used as an important navigational aid in their ocean travels. The declination of Sirius (distance from the celestial equator) matches the latitude of the archipelago of Fiji at 17°S and thus it passes directly over the islands each night. Though Sir- ius is not as "constant as the northern star" i.e., Polaris, it Bowling Scores Monday Night Mixed November 23, 2015 Scores over 200: Ron Elliott - 201 High Single Ladies: Anita Elliott - 215 High Single Men: Ron Elliott - 239 High Triple Ladies: Anita Elliott - 548 High Triple Men: Ron Elliott - 560 December 7, 2015 Scores over 200: Anita Elliott -202 High Single Ladies: Wendy Ritchie - 220 High Single Men: Charles Green -216 High Triple Ladies: Anita Elliott -561 High Triple Men: Charles Green -586 Bowling scores Lucknow Town and Coun- try Bowling Scores for Dec. 17 Games over 200: Anita Elliott -208 Games over 175: Shirley Kennedy -179 High Single Ladies: Anita Elliott - 208 High Double Ladies: Anita Elliott - 339 High Single Men: Jim Springer - 162 High Double Men: Jim Springer -288 Team STANDINGS/ POINTS Pansies -26, Tulips -22, Hyacinths -19, Snowdrops -22, Daffodils -18, Daisies -19 lucknowsentinel.com was still a useful navigational reference when it was visible in the S. Pacific sky. It is true that planets like Venus and Jupiter can be brighter than Sirius, but to the ancient astronomers, planets were unpredictable in their nature (they changed their brightness and wandered in the sky!) and so they could not be relied upon to mark seasons or annual events. In addition there were other "new" stars -nova and supernova, that also out- shone Sirius on a handful of occasions in recorded history. The four most famous supemo- vae are those that occurred in 1006,1054 (Crab Nebula), 1572 (Tycho's Nova) and 1604 (Kepler's Star). Each of these was brighter than Sirius, -the first two even outshone the brightest planet, Venus. But in spite of their remarkable bril- liance, the nova were alltempo- rary, while Sirius shone steadily and reappeared in the same part of the sky like clockwork Modem astronomers know many details of the most famous star after Polaris. Most remarkable is that itis actually a pair of stars revolving around each other very closely. The two are only as far apart as Uranus is from our Sun and take about 50 years to complete one orbit. The main star in this binary sys- tem, Sirius A, is a relatively nor- mal star, and the brighter of the two components. It is 70% big- ger than Sol, has twice the mass of our Sun and is about 25 times more luminous. The other component, Sirius B, discovered in 1862 while testing a new telescope for the Dearborn Observatory, revealed itself to be an extreme companion. It was found to be smaller in size than the Earth (by about 1000 km), but had 98% the mass of our Sun! If effect, it is a star packed down into a planet's volume, making it a super -dense object com- posed of atoms where the nor- mal space between the elec- trons and nuclei has been pretty much squashed out. Dubbed "white dwarfs'; the density of these stars is so great that a cubic centimeter (approx. the size of a sugar cube) would weigh 1 tonne (1 metric tonne = 2200 pounds) and be a tough job for a forklift to pickup off the ground! In spite of the amazing char- acteristics of Sirius -B, now affectionately known by astronomers as "the Pup", Monday mixed bowling scores Lucknow Monday Night Elliott - 237 Mixed bowling scores for High Single Men: Charles Dec. 14, 2015. Green -234 Scores over 200: Anita Elli- High Triple Ladies: Anita ott - 237, Charles Elliott -591 Green- 234. High Triple Men: Charles High Single Ladies: Anita Green- 585 Lucknow Tuesday bowling scores Lucknow Tuesday Night Finnigan 264. Bowling scores for Dec. 22, HIGH TRIPLE 2015 are in. FEMALE: Lea- Anne Hal - Over 200 Scores: Brad denby 547. MALE: Charles Engel 228, Charles Green Green 635. 222, 223, Anita Elliott 215, Ron Elliott 204. TEAM STANDINGS HIGH SINGLE TURDUCKENS 30, FEMALE: Lea -Anne Hal- NATIVES 26, NO NAMES 26, denby 242. MALE: Kevin DANCING CLOVERS 14 Lucknow Hockey Scores Junior Initiation team scores for Dec. 12, 2015 Lucknow (1) vs Ripley (20) in Lucknow Goals: Ainslie Johnston. Assists: Olivia Mabon Lucknow (10) vs Tiverton (13) Dec. 20, 2015 Goals: Marlee Courtney (8), Ainslie Johnston and Parker Doiron. Assists: Brody Doiron (2), Layla Andrew, Ayden James, Josh Courtney, Trent Hal- denby, Hunter Greig, Olivia Mabon, Bayne Simpson. Loa king SE 9;40 lin) mid-Decl nn Orion s Ock astronomers airi i astronomers were not sur- prised when its high density was discovered. An equally bizarre star was found a few years earlier in the constella- tion Eridanus the River. The first white dwarf was actually 40-Eridani-B, but the Pup still holds the record for having the highest density in the entire group of white dwarfs. When the winter clouds clear and the sparklers in Orion and Canis Major are shining stead- ily, it is actually possible to see the Pup with amodest sized tel- escope. The ones of the Fox Troy Patterson/Kincardine News Observatory can easily do the job. Check the BAS web site www.bluewaterastronomy. com for upcoming observing sessions. Becoming a member also provides the added oppor- tunity to observe on a spur-of- the-moment basis. The veter- ans usually there on those nights will be happy to show you both the Dog Star and the Pup and even help you cele- brate seeing it with a warm cup of coffee! Extra help is also appreciated when it comes time to clear the path to the observatory of snow. go -,A1 ant gocitireafivi f't t , A Alt We're displaying our holiday cheer, To thank everyone for stopping here And for your winning attitude, You surely have our sincere gratitude... So without any fanfare or further delay Please accept our best wishes for a great holiday! 4- Bruce Willits Please note: �illits Tire Service Willit's Pool will be ,.�,, Barb Willits closed Januar gepoy SWimniers February` f