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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.
Review: A Ray of Light in a Sea of Dark Matter
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What is it?
It�s an amazing revelation of modern cosmology to realize that we�re comprised of the rare exceptions of the universe. Baryonic matter, the stuff that you, your Iphone and radio telescopes are made up of, is the left over minority in the cosmos.
It turns out that it�s all dark, at least to our limited primate eyes. �A Ray of Light in a Sea of Dark Matter by Charles Keeton is a short work which narrows in on the subject, looking at the discovery and history of the hunt for dark matter and where the research and the field of cosmology might be headed. Part of the Pinpoints series out from Rutgers University Press, A Ray of Light looks to address a modern question of science in a simple and concise way.
We live in a golden age of astronomy in a time when hard data and evidence has led the study of cosmology and the universe from the realm of philosophy to science. One of the most remarkable things that science also tells us is that from atoms to the depths of interstellar space, reality is mostly� nothing. And though the revelation that a major chunk of the universe is comprised of unseen dark energy and dark matter may seem like a hand-waving argument, there is good evidence for researchers to believe that this must be so.
Mr. Keeton walks us through this bewildering universe of exotic particles, supernova standard candles, and gravitational lenses. Like the Big Bang theory of cosmology itself, we�re seeing a picture of the universe emerge, a redundant bulwark where multiple lines of evidence all point towards the same conclusion.
An associate professor of physics and astronomy at Rutgers University and a research astrophysicist with more than ninety articles in astronomy journals to his name, Keeton knows how to get obscure but key ideas in astronomy across in a clear and concise manner.
Is dark matter �MACHO,� as one school of thought suggests, or �WIMP-y?� The names refer to Massive Compact Halo Objects, or non-luminous or faint objects such as black holes or dwarf stars that may litter the outer galactic suburbs, versus WIMPS, or Weakly Interacting Massive Particles which, though producing reliable effects on small scales, may dominate the large scale picture of the universe as a whole. It is strange to think, WIMPs may be in the very room that you sit and read this in, right now. WIMPs seem to be winning out over MACHOs right now, and several exotic detectors, such as ones buried in an iron mine in Soudan, Minnesota and IceCube (the observatory, not the rapper) looking for neutrinos in Antarctica are on the hunt.
Much of this evidence comes from looking at the rotation rates of galaxies and motions of galaxy groups such as the famous Bullet Cluster. This is science at its best, as predictions of dark matter are set to become theories and laws.
Be sure to read A Ray of Light in a Sea of Dark Matter to get a handle on a fascinating facet of modern cosmology!
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