AJ's Cosmic Thing version 1.1 revision notes

The version 1.1 Cosmic Thing is a slight revision of the original code, bringing it more into compatibility with existing browsers.

The original Cosmic Thing was JVM 1.0.2-compatible code (written using the original Sun JDK 1.0.2, sometime in 1997, if memory serves). Since this release, Java has evolved some, and I figure it's well past time that the Thing caught up.

The rev 1.1 Thing was compiled in August of 1999 by A Milne, a systems analyst currently living and working in the Washington, D.C area.

Mechanism

The Thing works by reading a (proprietary) database file of the brightest objects in the night sky (down to mostly sixth magnitude, though I included a number of deep sky objects that are fainter), and doing a simple set of calculations based on the date and time (which it first converts to Julian date) and observer position (longitude/latitude) entered to determine where each object should appear in the sky. It's mostly trigonometry, and not terribly complicated — there are a number of sources for these formulae — on the web, you can consult Nasa/JPL's library of IDL routines (most of the Thing's formulae are ported from these). In print, consult Peter Duffett-Smith's works (he has a few), or, for the irredeemably precise, there's Meeus' Astronomical Algorithms.

Acknowledgements

I really must thank the people who contributed images for the Thing's library — please patronize their sites — the URLs appear below the images. I had meant to build a larger library of images, but my patience for writing solicitous email is sadly less than my patience for writing code, and I'm not a CCD kinda guy myself. Anyone out there who wants to volunteer images, please do get in touch with me.

Thanks also to Jack Brezina, at the mighty Times of Minden, where I was when I first wrote this thing