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[...] Struve 3053 in the constellation Cassiopeia. Another star that vies for the title of the �Winter Albireo�, this colorful double would probably also be a star party favorite if it were just a pinch above [...]
The Sky is Waiting.
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Pictured is a Delta IV rocket launch from Cape Canaveral on November 21st, 2010. The image is a 20 second exposure taken at dusk, shot from about 100 miles west of the launch site. The launch placed a classified payload in orbit for the United States Air Force.
Difficult but not impossible to catch against the dawn or dusk sky, spotting an extreme crescent moon can be a challenge. The slender crescent pictured was shot 30 minutes before sunrise when the Moon was less than 20 hours away from New.� A true feat of visual athletics to catch, a good pair of binoculars or a well aimed wide field telescopic view can help with the hunt.
The Sun is our nearest star, and goes through an 11-year cycle of activity. This image was taken via a properly filtered telescope, and shows the Sun as it appeared during its last maximum peak in 2003. This was during solar cycle #23, a period during which the Sun hurled several large flares Earthward. The next solar cycle is due to peak around 2013-14.
Located in the belt of the constellation Orion, Messier 42, also known as the Orion Nebula is one of the finest deep sky objects in the northern hemisphere sky. Just visible as a faint smudge to the naked eye on a clear dark night, the Orion Nebula is a sure star party favorite, as it shows tendrils of gas contrasted with bright stars. M42 is a large stellar nursery, a star forming region about 1,000 light years distant.
Orbiting the planet in Low Earth Orbit (LEO) every 90 minutes, many people fail to realize that you can see the International Space Station (ISS) from most of the planet on a near-weekly basis. In fact, the ISS has been known to make up to four visible passes over the same location in one night. The image pictured is from the Fourth of July, 2011 and is a 20 second exposure of a bright ISS pass.
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Next to the Sun, the two brightest objects in the sky are the Moon and the planet Venus. In fact, when Venus is favorably placed next to the Moon, it might just be possible to spot the two in the daytime. Another intriguing effect known as earthshine or ashen light is also seen in the image on the night side of the Moon; this is caused by sunlight reflected back off of the Earth towards our only satellite.
A mosaic of three images taken during the total lunar eclipse of December 21st, 2010. The eclipse occurred the same day as the winter solstice. The curve and size of the Earth�s shadow is apparent in the image.
AstroEvent: Herschel 3945-A Clone of Albireo.
Probably the most famous star party doubles are Alcor & Mizar in the Big Dipper and Albireo in Cygnus. Both provide a good, wide separation, and in the case of Albireo, a good color contrast. Plus, double stars provide a good �punch through� of the light pollution haze for down-town astronomy, and may save the show when the Moon or planets aren�t above the horizon and even the best nebulae such as M42 evoke remarks like �what, you mean that fuzzy smudge?�
�but did you know there is a binary star known as the �Winter Albireo?� sometimes called 145 Canis Majoris or Herschel 3945, this colorful binary lies roughly midway between Sirius and the variable star UW Canis Majoris. First noted by William Herschel, I think it�s bordering on naked eye visibility at +5th magnitude has something to do with its obscurity. Still, it is worth the hunt; the pair is colorful like Albireo with a sapphire-orange contrast at about 27� arc seconds separation. And like the optical double Albireo, H3945 is a true binary system at 258 light years (component HIP 35213) and 6,523 light years distant (component HIP 35210). Be sure to add this hidden gem to your repertoire this star party season� you�ll be the hit of the show!
The coordinates for H3945 are;
R.A. 7h 17� 36� Dec. -23� 18� 55�
The Astro-term for this week is: Position angle. This is one of the visual elements that astronomers use to describe a binary star system; the other is angular separation. The two work like coordinates with the primary (the brighter of the two at the center and the position angle measuring the deviation from the north or south celestial pole. Keep in mind, the position angle and separation of a given pair is only from our vantage point; the actual orbit may be oriented anywhere from edge on to face on to our line of sight. The separation and position angle of a pair also can slowly change as the stars orbit one another. In the case of H3845, the current position angle (P.A.) is 55�, which will slowly change over the centuries as our respective motions about the center of our galaxy alters our terrestrial vantage point.