|
|
 Because light behaves in some ways like a wave, it is bent or “diffracted” by a telescope’s structure (the edges of the optical tube, for example). This happens in the same way that ocean waves are partially bent or turned in a new direction as they pass a dock piling or the corner of a jetty. This scattered light prevents a star from being focused to a point. Telescopes always show stars as small disks of light (called Airy disks, after British Astronomer Royal Sir George Airy, 1835-1892). The disks are surrounded by faint rings of light called diffraction rings. The size of the Airy disk is determined by the aperture of the telescope – the larger the aperture, the smaller the Airy disk. The illustration shows the simulated Airy disk of a star seen through an unobstructed refractor. The brightness of the first and second diffraction rings has been emphasized for clarity. |
Home | How to pick a telescope | Telescopes | Accessories | New Products | Used & Demo / Special Sales | Binoculars & Spotting Scopes |
Link Support
Terms of Sale | PRIVACY POLICY 7/1/2004 | Fine Print
Toll-Free Telephone Astronomics: 800-422-7876; Christophers, Ltd.: 800-356-6603
Alternate Telephone: 405-364-0858 24 Hour Fax Line: 405-447-3337
Telephone Hours: Monday 8 AM - 6 PM CST
Tuesday-Friday 8 AM - 8 PM CST
Saturday Noon - 5 PM CST
Store Hours: Monday-Friday 9 AM - 5 PM CST
Saturday Noon - 5 PM CST
Astronomics / Christophers, Ltd.
680 S.W. 24th Ave.
Norman, OK, 73069
© 2009 by Ad-Libs Advertising, Inc. All rights reserved
|
|
Printer friendly version
Email page link to a friend