Weekend Stargazer: October 20 – 22

Uranus chart
Use this chart to locate Uranus this weekend.

Uranus reached opposition on Thursday, which makes this weekend a good one for getting acquainted with the faraway world.

Uranus was the first planet discovered after the invention of the telescope. British astronomer William Herschel found it with his 6-inch reflector from his home in Bath, England, in March 1781. When Herschel stumbled across Uranus, he mistook it for a comet. Only after months of accumulated observations was an orbit calculated and the planet’s true nature became apparent.

Currently, slow-moving Uranus is a 5.7-magnitude dot residing in Pisces. As the chart above shows, the planet is positioned roughly 2 degrees west-northwest of 4th-magnitude Omicron (ο) Piscium. Even under light-polluted skies, Uranus is within easy reach of binoculars, though you may have some trouble distinguishing it from nearby stars. This is where a telescope comes in handy. Once you’ve located the correct field, bump up the magnification and look for a tiny, pale-green disc. That’s Uranus. It spans only 3.7 arc seconds, so there’s not much to see—the fun lies in repeating Herschel’s discovery. Even with a much smaller telescope, you should have little trouble finding the planet. After all, you have the considerable advantage of knowing exactly where to look, and what you’re looking for!

To read more about what’s happening in the current sky, be sure to check out my regular This Week’s Sky column at SkyNews.ca.