SUNSET: 
A Scale of Seeing
Amateurs long have recorded the seeing quality in their observing logbooks on a rather subjective scale of 1 to 10, with 1 hopeless and 10 perfect.
A Pupil Primer: How Big Should a Telescope's Exit Pupil Be?
Image brightness, magnification, and why the old ideal of a 7-millimeter exit pupil is not so ideal at all.
Light Pollution In The Night Sky
Light pollution has become so pervasive that it compromises the view of the universe for an estimated 90 percent of Americans.
8 Backyard Observatory Mistakes to Avoid
Here are a few potential problems that you might not see on your blueprints.
Binocular Basics: Glossary of Binocular Terms
Exit pupils. Eye relief. Image stabilization. What matters most for astronomers? Our expert explains it all.
Collimation Tools
Three tools are commonly used to collimate Newtonian reflectors.
Freeware from Sky & Telescope
Handy — and free — observing and optics utilities.
Astronomy Software: Public Domain, Freeware, and Shareware
Dozens of free or inexpensive computer programs can aid your observing or simply allow you to explore the sky.
BASICally Speaking
Suzanne Rich From a casual exploration of the new-upload libraries of online services, and seeing recent freeware and shareware offerings, there is no question that plenty of programmers are still hacking away in their dens and basements. Furthermore, the creators of these utilities are more imaginative than those nearly two…
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Thank you for submitting your observing report to Sky & Telescope's AstroAlert service. If we have any questions about your data, we'll contact you by e-mail. Please note that at present we are interested only in reports following up a nearby-supernova alert. Observations in response to other types of alerts…
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Results of Nearby-Supernova AstroAlert Test
Our February 2003 AstroAlert test went very well. Here we report on what we learned, thanks to the enthusiasm and dedication of the test's participants.
