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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.
08.11.09:Does Cometary Mass Extinction Need to be Rewritten?
Comets are cause all mass extinctions in Earth’s history, right? Maybe not, if new research is correct. Simulations run by the scientists at the University of Washington now suggest that the giant planets of Jupiter and Saturn may do a much more through job of cleaning up incoming debris than is generally realized. Short period comets such as Halley’s are generally accepted to be denizens of the Kuiper belt, which extends out to 100 Astronomical Units (A.U.s), while much more numerous populations of long period comets are theorized to come from the Oort cloud, a massive solar system-engulfing sphere at a distance of 1,000 A.U. to up to 3 light years distant. Traditional cometary mass extinction theory states that when a star passes close enough to the shell of the Oort cloud, a rain of comets are pried free and the inner solar system becomes a celestial shooting gallery for a million years or so. Simulations, however, suggest no more than three impacts could have occurred over the last 500 million years or so, fuel for at best maybe a minor extinction event or two. Then there’s the pesky affair of some extinct species shown to exist above the K-T iridium layer… doubtless, the case of mass extinction is a thoroughly messy business. As reported earlier last month in this space, more than one impactor is suspected in the extinction of the dinosaurs. Examination of other inner solar system bodies should pin down the frequency, duration, and average number of killer comets, as the Moon, Mars and even Mercury have relatively little erosion and would be potential targets as well. Any incoming comet stands a 40% chance of having its orbit altered by Jupiter, as happened to Hale-Bopp in the late 90′s. Thanks, Jove!