This interactive tool is designed to give you answers to your commonly asked questions about your telescope's performance when changing eyepieces and accessories.
Ceres, the biggest asteroid and brightest dwarf planet,shines at magnitude 6.9 or brighter from December 12-25.
Now you can calculate the dates and times (local and Universal Times) when the center of the Great Red Spot should cross Jupiter's central meridian, the imaginary line down the center of the planet's disk from pole to pole.
Click here to find the positions of Jupiter's moons and the Great Red Spot.
Here are a few hints to enhance your meteor-watching experience.
As the moon wanes in the gibbous phase in the nights to come, see if you can find and observe some of 100 of Charles Wood's classic lunar hit list, including craters, basins, mountains, rilles, and domes.
Meteors, meteoroids, meteorites, and fireballs — keep all these look-alike terms straight.
Mark your calendars for August 21, 2017 — when the Moon's umbral shadow will race coast to coast across the United States for the first time in nearly a century.
We'll see a "blue Moon" next Friday, but what does that mean? From the Middle Ages to the game of Trivial Pursuit, a folklorist explores the origin of the phrase.
The "King of Planets," which will dominate the evening sky from late 2011 through early 2012, is a captivating sight no matter how you look at it.
The two brightest asteroids are close to each other in late 2012 and early 2013. Moreover, they're traversing one of the most interesting areas in the night sky.
The two brightest asteroids are in fine view for binoculars or a telescope. Here are instructions and charts to find them.
Lurking in the seemingly changeless constellations are a few inconstant stars that pulse and eclipse. Here are a dozen variables that are easy to observe.
Occultations of stars and planets by the Moon and asteroids are exciting to watch, and amateur occultation timings can have real scientific value. But first you need to know what occultations will be happening in your area.
Vesta shines at magnitude 7 or brighter through mid-May 2010.
The Triangulum Galaxy shows more detail through backyard telescopes than any other galaxies except the Magellanic Clouds and our own home, the Milky Way. But M33's treasures don't just jump out and grab your eye. To see them, you need dark skies, patience . . . and this guide from the December 2004 issue...
Thanks to a generous bequest, each year amateur astronomers earn a beautiful plaque and a cash prize for discovering one or more comets.
Robin Leadbeater of Wigton, UK, has reported the first sign of the long-awaited eclipse of Epsilon Aurigae, one of the most remarkable eclipsing variable stars in the sky.
Beta Lyrae, an eclipsing binary, is one of the brightest and easiest-to-find variable stars in the sky.
For a few days each May, you might see the International Space whenever it passes overhead throughout the night.
The Galilean-satellite events published in Sky & Telescope's May 2008 issue are incorrect. Here's the correct listing.
You can see 9% more Moon than just what's on the near side thanks to lunar libration.