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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.
The Algonquin Indians had names for each of the seasonal Full Moons, many of which survive today. The Full Snow Moon pictured occurs in the month of December, when the first large winter storms coat the ground with snow. This Full Moon also tends to fall near the Winter Solstice, and thus rides high in the nightly sky opposite to the Sun on long winter nights.
Every rocket launch is unique, but twilight shuttle launches where by far the most impressive. The image pictured was of the April 5th, 2010 launch of Space Shuttle Discovery from the Kennedy Space Center at dawn. The exhaust plume caught the rising Sun overhead just right, and numerous noctilucent clouds persisted right up until sunrise. Unfortunately, space shuttle launches are now relegated to the pages of history.
The Elusive Wow by Robert H. Gray.
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Nothing fires the scientific imagination like the search for extraterrestrial intelligence. And likewise, no discovery would have further implications to our own existence and what it means to be human. Plus, it would just be darned interesting to get to know something about them. How unique are we?
Is intelligence and self-awareness inevitable, or a rarity? What other unthought-of avenues can life take? This is all thought-provoking stuff tackled by the subject of this weeks’ review.
The Elusive Wow: Searching for Extraterrestrial Intelligence by Robert H. Gray is not “just another SETI book…” Like Seth Shostak’s Confessions of an Alien Hunter, The Elusive Wow is an intensely personal journey. The author became fascinated with a signal (the Wow in question) received by the Big Ear telescope in 1977 enough that he taught himself radio astronomy and started his own grass-roots SETI campaign. But far from being a Ham-radio tinkerer, Mr. Gray has actually gotten time on the radio telescopes of the Very Large Array in New Mexico and facilities in Tasmania to scan the Wow region again. The Wow signal originated from an area in the constellation Sagittarius in the general direction of the galactic core. The signal rose briefly to 30 times the radio background and was within about 10-kilohertz of the magic hydrogen frequency-line of natural cosmic emissions that someone might use to grab our attention. The author further demonstrates the unlikelihood of Wow being from terrestrial or satellite interference, and the possibilities we are left with are, once again, darned interesting.
Could Wow have been an artificial beacon, periodically sweeping the sky? The author points out that such as strategy would be much more energy efficient than sending a broad omni-directional pulse continuously. Along with discussing the emergence of his own project, dubbed the Small SETI Radio Telescope (link), the author traces the history of SETI, the emergence of life on Earth, and thoughts on the existence of extraterrestrial intelligence. The Drake equation famously laid out a road map to get the discussion started on just how many civilizations might be out there for us to talk to. The Fermi Paradox further posed the question of just “where are they?” I’ve never seen the difficulties faced by SETI laid out so succinctly as in this book. Folks may wonder why SETI has yet to hit pay dirt, but fail to realize that it’s been a spurious affair at best over the past half century. If the Wow signal only points at us on every 2nd Tuesday at 11:01 AM, for instance, it could have been easy to miss. Or perhaps everyone’s listening but no one is transmitting? In which case, only our military radar would give us away, especially as our civilization becomes more reliant on closed transmissions and becomes “radio quiet”.
Or perhaps we’ll detect signs of life by more passive means. We’ve yet to turn over every stone in our own solar system, and places like Mars, Europa, or Titan may yet harbor microbial life. Detection of signature molecules like chlorophyll in an exoplanets’ spectra may hint at some interesting goings on, and, more ominously, detection of synthetic elements like plutonium may signal a civilization that snuffed itself out in a nuclear conflagration. These types of detections may be possible in our lifetime, and will give us pause to think. We’ve even sent five spacecraft (two Pioneers, two Voyagers, and New Horizons) zooming out of our solar system as “messages in a bottle…” it’s fun to think just how many derelict alien spacecraft may be adrift around the Milky Way at present. (Perhaps worthy of a modified Drake Equation?)
Do check out The Elusive Wow for an interesting snapshot of a fascinating discipline. Will “The Big One” be discovered in our lifetime?