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Instructor: Victoria Dowling PhD.
Topic:
Backyard Astronomy for Beginners
Project Report
December 18, 1997
Background
The two fundamental levels of astronomy: professional and amateur, often mix and match at the higher levels of study. Observatories often work with experienced amateurs to help gather research data. Nearly all comets are discovered by amateurs because of restrictions in observatory schedules and research priorities. Variable star research, (stars that exhibit variable levels of magnitude), is another example of research done nearly exclusively by amateurs.
Most web sites are geared to the upper levels of astronomy research. The web is an excellent repository for the study of astronomy. Nearly all institutional and educational research is now posted on the web, in some form. The introduction of the Hubble Space Telescope has added a level of study nearly beyond the human imagination. For the most part, this is good news for the study of astronomy. However, in the quest for a deeper knowledge of the subject, the information that becomes available is often beyond the reach of the beginner.
Backyard astronomy is the study of astronomy using fundamental physics, fundamental observation principles, using basic optical equipment. Viewing the skies with the naked eye in a remote location, far away from the light pollution, can be as rewarding an experience as a trip to an observatory. Most amateurs do not get the opportunity to visit a major observatory. So, while web images are usually a spectacular display, they will remain elusive to the observations of the typical amateur.
To correct this shortcoming, web sites can be established that help bridge this information gap. Entry level sites can be established to assist the beginner in addressing the realities of observation opportunities. Every object in the sky, visible with the naked eye, except for one: (M31; the Andromeda galaxy) is within our own Milky Way galaxy. Spectacular visions of far away galaxies are visible only with costly optical equipment. Even modest 8" to 10" telescopes will not show anything that resembles a Hubble image.
Site Development: General Comments
I have established my introductory astronomy web site to allow the casual observer to better understand the possibilities, as well as the limitations, regarding observation opportunities. I have introduced images from my own collection to help serve as examples of the typical upper limit of image resolution from an affordable telescope. Image resolution is the key factor in any optical instrument. Magnification has relevance only if the optics have a coinciding resolving power. There are several reputable manufacturers of quality telescopes, such as Meade and Celestron. Quality binoculars are an excellent and relatively inexpensive alternative for the beginner.
Introduction of high-resolution, Hubble images to the introductory page could detract from the purpose of the site. It is important to establish realistic reference points and expectations for typical amateur viewing. Agencies such as NASA and the Jet Propulsion Laboratory do a fine job providing access to their extensive galleries of photos and documentation. I have added their links to my site.
In July of 1996 I had the opportunity to observe the some of the impacts of the Comet Shoemaker-Levy fragments on Jupiter. Even with my 8" Celestron telescope, the impacts resembled tiny flecks on the surface of Jupiter. Had this event happened on earth, it would have been a global catastrophic event. In spite of the relative image size, the observation was a breathtaking experience. Observatories showed significantly more detailed images. The HST showed even more detail. However, the naked eye, binoculars, and small telescopes showed nothing at all. The comet impact was a well publicized, major astronomical event, so the amateur needs to know what the appropriate tools are. The 1997 viewing of comet Hale-Bopp needed no equipment at all to view. That is also the case with the periodic meteor showers. A successful web site should simply tell you when and where to look for these naked eye objects.
I introduced a weather section into the site. Weather conditions are an obvious factor in observation opportunities. Clouds and dew are the curse of astronomers. Dew can be controlled on an instrument, but the problem of cloud cover still has to be addressed. I inserted a national menu of five-day forcasts from The Weather Channel. I linked a site to UMASS and vicinity. I linked the closest site to my own viewing area. I also inserted the site that shows the most current regional satellite photo. This shows the actual real time cloud cover. Also linked was the regional Doppler radar image. This shows specific areas receiving some form of precipitation. This would be a factor if you needed to protect an optical instrument. Even a cloud covered night doesn't need to deter a viewing opportunity. Sometimes cloud breaks appear and opportunities are reestablished. The satellite photo serves as a predictor of potential breaks in clouds and other clearing patterns.
Site Construction: General Comments
The site is in the introductory phase for the purpose of this project. I will use this site later as a repository for my astrophoto collection as well as any relevant information and links that become relevant to amateur astronomy. The photos inserted in the site were scanned and compressed into jpg format. Jpg format images sometime lose their image quality more than images in gif format. The needs of the site as well as the maximum allotted capacity of the internet service provider, can influence the compression size of the graphics. I use AOL as my ISP. Each screen name allows 2MB space for each individual home page. AOL offers four screen names for each account. That allotment gives you a potential web site, with links to each other, with a capacity of 8MB.
There is a compromise between load time and the use of uncompressed or animated images. My astronomy web site takes about 30 seconds to load at 28.8kb. By removing the introductory rotating graphic (104kb), the load time is reduced to 15 seconds. The compromise is more significant in sites, such as astronomy, art, commercial sites, etc., that relate to a visual media. I developed a parallel site, without the rotating earth, until I find a more suitable replacement for the high content graphic. Content should be the primary consideration, but bells and whistles are a significant visual focus on the web. Twenty seconds seems to be the industry load time "comfort zone." Anything over that limit becomes a risk of losing the undivided attention of the site guest. I tried to keep the primary site to a limit of two typed pages.
I used AOLPress as an editing and web construction tool. It is a free, downloadable shareware program sposored by AOL, but interchangeable with other ISP's. This program allows for a WYSIWYG presentation. Insertion of images altered the presentation on several occaisions, but the program allows for editing tools in the HTML screen option. Other quality editing programs include: Microsoft Front Page 98 and Hot Dog Pro.
