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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.
Astro-Event: A Very Old Moon Pairs with Venus.
This week�s astronomy challenge ties in two potential visual challenges: sighting a very slender crescent Moon and a�daylight occultation of Venus.�A grouping of the next two brightest objects in the sky after the Sun is always a treat; the challenge comes from the fact that the celestial pairing will be very close to a brightening dawn horizon. Venus just passed inferior conjunction on October 28th; it will sport a 2% illuminated crescent about 60� seconds in size at magnitude -4.2. The Moon, meanwhile, will be about 1% illuminated and reaches New on November 6th at 04:52 Universal Time.
At about 24 hours from New, both will be tough but not impossible to spot; start sweeping the horizon about 30 minutes prior to sunrise for best results. Lucky observers positioned from southern Africa to Western Australia will have an additional challenge; a daylight occultation of Venus by the Moon on November 5 centered on 07:00 Universal Time. The best odds at catching this successfully would be to lock a polar aligned scope on Venus before sunrise and track it throughout the day. Europe and the Middle East latitudes will see a close pairing at sunrise on Friday November 5th, while the Americas will see the pair within a five degree field later the same morning.
The Astro-word of the week is: Parallactic Inequality. This is a factor that must be accounted for in the wonderfully complex motions of our Moon. This variation is caused by the parallax of our Sun and causes the Moon to be about 2� 7� ahead of its predicted position around 1st Quarter and lag 2� 7� behind around Last Quarter� to give you an idea how tiny an amount that is, the apparent size of a Full Moon as seen from the Earth is about 30�. Simon Laplace once theorized that measurement of the Parallactic Inequality of the Moon�s position would serve as an effective measurement of the Sun-Earth distance, without having to chase down infrequent transits of the planet Venus from barren parts of the globe. However, one would have to know the respective masses of the Earth and the Moon to a high degree of precession for this method to be effective, a tall order in 18th century science!