Monday, February 23, 2009
I started off the weekend with a bang! I have been talking about comet Lulin for months and haven't been able to view it because every time I had the chance the weather would not cooperate. Good ol sunny California, ya right LOL. Friday the 20th started out cloudy but in the evening as 3 of us showed up at the Luz Observatory the skies cleared. Well we started out by viewing Venus which was one of the best views I have ever seen of this planet. Then Pandora's Box was opened, oops no that was the front door of the observatory down stairs. Well we had an entire elementary class show up with their parents. Wow but the 3 of us can handle that no problem. So next we fixed the scope on Saturn because that ALWAYS wows the crowd. People just kept coming and coming LOL. Well to find out the night before the local news did a story on comet Lulin, plus we had advertised the public viewing in the local paper. Well needless to say we ended up with 97 people in the observatory that night. The line went around the scope platform down the stairs to a crowd filling up our large meeting room and lobby. WOW! We also had a direct link setup to the GAVRT radio telescope which is part of the Goldstone Radio Telescope complex on Ft. Irwin which was donated to the Lewis Center by JPL/ NASA. The kids love to actually move that big ol dish and watch it live via live video stream. Well anyhow the final count of bodies was right at 97. That is one of the biggest crowds we have had there. Well at 8:40 PST the Comet started to rise and we gave everyone a nice view of the comet along with many other objects that night. It really feels good to see public interest peak on events like this.
Wednesday, January 28, 2009
If you are an amateur astronomer, I do recommend that you try sidewalk astronomy. I have found it to be a truly rewarding experience. People are very appreciative of the effort and always have a great time. It is nice to take along a friend or another amateur astronomer for moral support. In fact, several telescopes really make it an event that will attract a crowd. The best time to go out is between First Quarter and Full Moon when deep sky observing is not possible. People love to see the moon through a telescope and are usually awestruck! When I started sidewalk astronomy, I never observed the Moon or planets for more than a minute or two during a session as I felt is was a waste of my time since I was only interested in deep sky objects. Now I enjoy lunar and planetary observing and have learned a great deal about these objects through my research which I conducted in order to better answer questions I was asked by the public. Anyways the best places to set up are areas of high foot traffic such as Barnes and Noble, and Starbucks. Attracting a crowd is easy when you have a telescope set up.Here is a picture of a small group around my scope in a Albertson's Supermarket parking lot. I had over 30 people come over to my scope and everyone enjoyed viewing the moon that night.
In the latter part of the eighteenth century, astronomers gained fame and wealth by discovering comets, still thought to foretell the future. One of these skywatchers was Charles Messier, who observed from Paris. Occasionally, M. Messier would chance upon a whitish blob, such as comets look when they are first seen. On August 28, 1758, he spotted such an object. Unfortunately, after watching it for a few evenings, he found that the blob maintained the same position among the stars, unlike a comet. Determined not to be fooled if he encountered the same object in the future, Messier determined and saved its coordinates. Over the next several decades, with the help of his colleague Pierre Méchain, many other entries were made in a list of deceivers. The list now contains 110 objects (though historians quarrel about the exact number), and are referred to as M1 through M110. A few objects had incorrect coordinates or may have been duplicates. It is generally agreed now that M101 and M102 are the same.This list has become the beginning observer's guide book, for it contains most of the interesting celestial objects to be found with a small (4" diameter) telescope. These objects include reflection nebulae, emission nebulae, planetary nebulae, open clusters, globular clusters, spiral galaxies and elliptical galaxies. Objects of all these types can look like a blob. (Modern telescope usually see open clusters as individual stars, but with the crude telescope Messier used many clusters looked like small clouds.) Interestingly enough, the first false comet Messier discovered was different from the rest. M1 is the Crab Nebula, the detritus from a supernova explosion.I mention all this because around the spring equinox it is possible to see all the Messier objects in a single night (sunset to sunrise). Only at this time are all of them far enough from the Sun to be seen sometime during the night (although M30 is quite difficult from latitude 40° north). Amateur astronomers call such an attempt a Messier Marathon. You'll need a dark sky, a medium-sized scope (4 to 8 inches in aperture, depending on experience), coffee, snacks and warm clothing. Of course you can see all of Messier's menagerie in bite-size chunks -- twelve monthly expeditions, four seasonal trips and so forth. But where's the fun in that? ?
My club the High Desert Astronomical Society is confirmed for a night of observing at the 60" reflector up on top of Mt. Wilson. The outing is scheduled for April. This is going to be an awesome experience and I can hardly wait to go. Here is a little bit of the history of the telescope.The 60-inch reflector at Mount Wilson was constructed in 1908. Hale used the 60-inch glass blank that his father purchased for him in 1896. George Ritchey finished the glass blank into a mirror of the proper size in the Mount Wilson optical shops in Pasadena, California. Ritchey also designed the tube and mounting for the telescope, which were built by the Union Iron Works in San Francisco. The design drew heavily on experience gained with the use of the 36-inch Crossley reflector at the Lick Observatory.The telescope is supported by a 15-foot tube, which contains eight separate steel tubes and cross-braces designed to provide a stiffer truss and support system than was originally found in the Crossley reflector. The mirror is supported by a system of levers in a steel housing attached to the bottom of the tube and is fork-mounted on the polar axis. Just below the fork is a 10-foot diameter mercury float-bearing system designed to carry the weight of the telescope. The telescope is moved with electric motors. The 58-foot dome of the telescope is built from steel, on a concrete foundation, with double walls for the free circulation of air. This design is necessary to minimize temperature variations which could alter the shape of the mirror.Hale designed the optical system of the 60-inch reflector so that the instrument could be used for a variety of purposes. As a Newtonian telescope it was an f/5 instrument for photography and low-dispersion spectroscopy. In a modified Cassegrain configuration, using a convex hyperboloidal mirror before the prime focus and a plane mirror at the lower end of the tube to reflect light to the side of the tube, it could be used at f/16 for spectrography and an f/20 for photography. Finally, as an f/30 Coude, light was reflected by an appropriately geared mirror through the hollow polar axis into a constant-temperature room housing a large spectrograph. This flexible optical system, which allowed the telescope to be used for photographic and spectrographic purposes, was a model for future large reflectors. After the trip I will write a blog and post photos of the trip. Now maybe we will do the same thing at the Mt. Palomar Observatory next year!