One of the real celestial treats through any size telescope is the giant planet Jupiter. Even a 2-inch scope will let you view its main markings and four largest moons. By watching the moons change their positions night after night, you can experience “real-time” astronomy. That would be a good start. If, however, you want to go deeper into Jupiter observations, I recommend Jupiter and How to Observe It by John W. McAnally (Springer, 2008). Even before...

On Tuesday evening, April 8, you can experience one of the most beautiful events the sky can deliver. Head outside no later than an hour or so after sunset (around 8:30 P.M. local daylight time) and look to the west. Your eyes should land immediately on the slender crescent Moon, oriented with its cusps standing nearly straight up from the horizon. Point your binoculars at the Moon to reveal a stunning sight: the bright Pleiades star cluster (M45...

There’s no better place to find astronomy related software than the web archive created by Astro Events Group of Ostend, Belgium. “Our compilation will actually never be complete,” says Patrick Jaecques, a member of the group. “We have updates about every week. It’s also the only part of our Dutch web site that is translated into French, German and English.” There you’ll find hundreds of programs for a wide variety of computing environments, including...

Update from January 9: Since our last update, we have received numerous tracking measurements of asteroid 2007 WD5 from four different observatories. These new data have led to a significant reduction in the position uncertainties during the asteroid's close approach to Mars on Jan. 30, 2008. As a result, the impact probability has dropped dramatically, to approximately 0.01% or 1 in 10,000 odds, effectively ruling out the possible collision with...

Happy Thanksgiving! Many of us will take this holiday as an opportunity to reunite with family and friends. We'll cook, enjoy a variety of food, nap, and watch our favorite football teams. Ok, then what? I have a suggestion. If it's clear, pull out your telescope. Better yet, have it already set up and ready to go. If you're like me, you won't be helping out much in the kitchen. Not that I don't want to, mind you. My talent just...

If you've been watching the Moon after sunset this week, you may have noticed it lies lower in the sky than usual (at least if you live at mid-northern latitudes). It's not your imagination — the Moon is figuratively scraping the treetops this week. Although this is no great mystery, it never hurts to remind yourself about the Moon's monthly and yearly cycles. The Moon's maximum altitude from any given location depends on its declination...