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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.
Review: The Journey to Palomar.
Any groundbreaking construction project has its own unique tale, and the ascent of some of the great telescopes of the world is no exception. This week, we look at PBS’s landmark documentary, The Journey to Palomar, the story of a man and the rise of American astronomy to pre-eminence on the world scene.
Hale in his natural habitat…hard at work circa 1905. (Public Domain Image).
George Ellery Hale was a genius who, like many before or since, was nearly driven to madness for his visionary efforts. Palomar traces the pattern he established for undertaking huge observatory construction projects, starting with his first goal that established a precedent for all others; the construction of Yerkes Observatory. The crown gem of the facility was the 40” inch Yerkes refractor, still the largest of its kind used for scientific research to this day. Yes, we know the French built a 49” refractor for the Great Paris Exhibition in 1900, but that beast proved unusable! The Yerkes refractor also marked an end for an era of 19th century astronomy; a larger refractor will probably never be built. An almost as revolutionary breakthrough was the moveable floor designed to bring the observer up to the eyepiece; this floor collapsed once shortly after construction. The film also quotes Simon Newcomb’s now famous remark that “We are probably nearing the limit of our knowledge in terms of astronomy” when in fact, the voyage had yet to really have begun!
The Yerkes 40″…Notice a famous somebody? (Credit: NPS.gov/Yerkes Observatory/University of Chicago).
A perfectionist, Hale was on a lifelong quest to build larger and larger instruments. This pursuit drove him westward to found the Mount Wilson observatory in California. With funding from the Carnegie Institution, ground was broken in 1904 and first light was achieved in 1908. The observatories built by Hale displayed a fundamental shift in thinking; it was slowly becoming realized that not only the instrument, but the site selected was crucial to astronomical success. Hale’s observatories were not just lone instruments, but research complexes dedicated to science and astronomy.
The venerable 100″ Hooker telescope. (Credit: The Mount Wilson Observatory).
But Hale wouldn’t live to see his final act play out; the construction of the 200” inch reflector atop Mount Palomar. Projects of this scale simply had no template to build off of; whole new techniques had to be devised for the figuring and polishing of the massive mirror. Construction began in 1936, and the promise of the Palomar observatory was perhaps the one great shinning light during the Great Depression. The initial glass pourings were true media events; the process itself was slow and tedious and had to be repeated several times. Corning Glass Works initially experimented with fused quartz in the initial castings but eventually settled on a new material known as Pyrex for its low thermal expansion qualities. Hale passed on in 1938; work on the telescope was halted during World War II but the instrument that now bears his name saw first light in 1949. Footage of the final polishing process is just plain cool to watch; did you know that final polishing was done with bare fingers? Ultimately, the engineers had to pry the 200-inch away from the opticians loving hands and simply proclaim the mirror as “done”; polishing might have continued to this day! Journey to Palomar also traces the story with comments by noted scientists and authors such as astrophysicist Wendy Freedman. The Hale telescope was to a generation what Hubble and Keck are today; I vividly remember Palomar being the pinnacle of astronomy as a child of the 1970s. These days, apertures are measured in meters, and several of Hale’s masterpieces now have the modern trappings of CCD cameras and adaptive optics to remain competitive. But Hale’s visionary mastery of astronomy gave us a glimpse of what might be possible, in a field where everything may truly never be known. Do give Journey to Palomar a look for a fascinating glimpse in astronomical history. The title is available via Netflix, but the truly good news for those who read this far is its still currently up on Hulu for free viewing! Now what would Newcomb thought of that and the idea of Internet astronomy?