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[...] but also in terms of time. The stars in the Milky Way galaxy, for example, are swirling around the galactic core to the tune of one orbit every quarter of a billion years � but the constellations you see from you [...]
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 of the Week: 26 August - 1 September: Spy the Core of our Galaxy!
Now for an unorthodox challege; a chance to locate something that may be visually unassuming, but very significant.
As summer winds down, the Milky Way vaults high in the evening sky. As viewed from Northern hemisphere mid-latitudes, the core bulge sits just above the southern horizon. Nestled in this bulge is something very special; the very core of our galaxy. Where you equipped with radio�wavelength vision,�(A very weird eye, indeed!) you would see an intense radio source; known as Sagittarius A* (Pronounced A Star)�this is an estimated�four million solar mass black hole that lurks at the core of our galaxy. It’s very much a forest through the trees situation; at visible wavelengths, the brilliant core is obscured by thick dust. Located about 26,000 light years distant, the point of no return boundary would fit within the orbit of Mercury!
The coordinates of the Galactic Center of our galaxy are as follows: Right Ascension: 17h45m40.04s, Declination: -29 degrees 00’28.1″, right on the Sagittarius/Ophiuchus border. Visually, the area is littered with dark nebulae and clusters, but the monster that it hides is indeed mind blowing!
The Astro-word of the week is Black Hole. A black hole is an object that is massive enough that the escape velocity exceeds that of light beyond a certain boundary, known as a Schwarzschild radius. They come in three flavors: mini-black holes, thought to be created directly after the birth of the universe (and yet to be directly observed!), stellar mass black holes, formed from a collapsed star about ten times the mass of our sun, and super massive black holes in the cores of galaxies, millions of times more massive than our sun. For a semi-mind blowing animation of stars at the core of our own galaxy, click here.