The Sky is Waiting.
Search AstroGuyz
Custom Search
Advertise on Astroguyz!
|
|
|
 |
|
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.
Review: The Drunkard’s Walk by Leonard Mlodinow.
A ‘Random’ Classic!
True randomness is just plain hard to replicate. Recently, an interesting discussion came up on George Hrab’s Geologic Podcast about whether it was possible to have levels of randomness. Few folks realize that what most people perceive as random is actually more ordered than one would think. Throw the dice long enough, and biases due to tiny imperfections will present themselves in the stats.
This week, we take a fascinating look at all that is random in The Drunkard’s Walk by Leonard Mlodinow. Mr. Mlodinow starts off with some classic mathematical conundrums straight out of statistics 101 and demonstrates just how ill-equipped our brains are to handle the world from a mathematical stand-point. For example, did you know that in the “Let’s Make a Deal” scenario, you have a better chance of winning if you switch doors on your second choice? Or that if the sex of one fraternal twin is known, the odds that the other twin is the same sex is not 1-out-of-2, but 1-out-of-3? Or that in a room of 30 people, the odds are pretty good that two people share the same birthday? Some of these we had heard before (A great many are wonderfully illustrated in the CBS TV series NUMB3RS) and some were new to us. Great companions to The Drunkard’s Walk would be The Calculus Diaries and Proofiness.
While the author doesn’t back away from the “Mathiness” to quote Buffy the Vampire Slayer, he also presents it in an engaging and accessible way. We live in a mathematically-based society, and whether its calculating batting averages or interest paid on a mortgage, math illiteracy can doom us to being deceived by numbers. The book mentions one of our favorite recent run-ins with randomness in recent years; when Apple 1st presented the IPod, folks began to complain that the shuffle mode would occasionally play the same song twice. And that’s just what you would expect from true randomness; play your IPod long enough, and you could expect to hear Iron Maiden’s Rime of the Ancient Mariner 2, 3, even a dozen times in a row. Apple had to insert an exception into the software, and our skewed view of random mode was restored.
As noted in the book, astronomers are also not immune to seeing patterns in the chaos, sometimes gaining deep insight, other times only to wind up chasing false chimeras. Kepler’s quest to link the five perfect solids with the classical planets and attempts to find physical underpinnings to the Titus-Bode law are some key examples in astronomical history. Our hunter-gatherer brains are great at seeing patterns, but sometimes this backfires making us see correlations out of mere circumstance. How many paranoid delusional individuals have fallen prey to an asserted hidden pattern in their lives?
Today, randomness or something close to it can be had through advanced algorithms or analysis of static or white noise. But even these have a slight bias that will show up over time. It’s sobering to think that the only true but unobtainable perfection in reality may be absolute randomness. The author also explains the often maligned concept of sample space and the gambler’s fallacy, which is the idea that a player or slot machine must be “due” after a certain run. The untold history of western mathematics and the understanding of the concepts of randomness alone make for an interesting read. Do give The Drunkard’s Walk a browse both before setting foot in a casino or a statistics 101 class. I’m also happy to report that this book was my first successful experience with downloading something onto our Kindle Fire from the local library… an experience worth repeating!