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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.
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.
Astro Event: A South Pacific Eclipse.
This year’s big ticket astronomical event occurs over a sparsely populated but beautiful track of our planet; we’re talking about July 11th’s total solar eclipse. Of course, it isn’t often that an eclipse doesn’t occur over the windswept Arctic or a war-torn banana republic… the Sun and sand of an island eclipse may just be the perfect combo. If you haven’t already made plans to catch one of the numerous cruises headed that way you may have to enjoy it vicariously with the rest of us via the Internet; this eclipse graces only a smattering of islands before making a brief landfall in South America across the Chilean-Argentine border at sunset. The path of solar totality will not grace our planet again until November 2012 in another South Pacific eclipse that intersects this month’s path! Its maximum length of 5 minutes and 20 seconds occurs over open ocean. Two very interesting sites for viewing include Easter Island and just off of the coast of French Polynesia and Tahiti; the more adventurous may want to head for the Cook Islands site of Mangaia, which lies right along the centerline. Weather prospects may favor the northern hump of the path, with a mean cloudiness of less than 50%… but for sheer beauty and landscape photo ops, Easter island will be your best bet. No doubt most of humanity will experience this one vicariously via the web; follow @Astroguyz via Twitter, as we’ll post where online to watch this extra-ordinary event in the days leading up to the eclipse!
The Astro-term for this week is Metonic Series. A metonic series of eclipses arises from the fact that the period of 19 tropical solar years is very nearly equal to 235 synodic months. This was first recognized by the astronomer Meton of Athens in the year 432 B.C. The error of difference is 2 hours per 19 years, and this accumulates to a full calendar day every 219 years. A metonic cycle of eclipses will share the same calendar date in groupings of 4 to 5 per series… for example, the first eclipse related to this month’s was on July 11th, 1953 and the last will be 19 years from now, on July 11, 2029. Do not confuse metonic series with saros cycle, which is independent of the solar calendar and based on a period of 223 synodic months. So what, you say? Well, metonic series not only factor into eclipses landing on the same date, but also play a role in calculating when the Moon will appear at the same phase in the same position again… metonic series even play in to trajectory calculations for lunar bound spacecraft, as well as serving as a basis for the Hebrew calendar and the computation of Easter!