Not many people pay attention to the 7th planet. Sure, sure we have lots of fun with its name, but have you have stepped out at night to see it with your own eyes? Several nights ago under a dark sky, I could faintly see Uranus just by looking up at the right spot in Pisces the Fish, its haunt for the past few years. No binoculars, no telescope. How many thousands of eyes over the centuries must have run across this point of light? Not a one knew it stood apart until English astronomer William Herschel “put it on the map” in 1781.
Dark skies were the norm hundreds of years ago. Now they’re the exception. That’s why I don’t expect you to just walk out and find Uranus. But the good news is a pair of binoculars will do the job, and the planet is ideally placed for viewing during the early evening hours.
Start with the giant Square of Pegasus, a big, connect-the-dots square of stars high in the southeastern sky around mid-month. Next, shoot a diagonal line through the Square downward into the dim constellation Pisces to the two faint stars Epsilon and Delta Piscium. Uranus lies a short distance directly below Epsilon.
It looks just like a star, similar to several in its neighborhood. That’s why the detailed map will help you to figure out exactly which is which.
Uranus moves westward until the day after Christmas, then resumes its normal eastward motion. All the outer planets take a several-month-long side jaunt to the west around the time they’re closest to Earth. It’s called retrograde motion because the planet appears to stop and move “backwards” (west) in retrograde. What’s really happening? The faster Earth passes the slower, more distant planet, making it look like it’s falling behind. We see the same thing happen when passing a car on the freeway – as we speed by, it temporarily appears to travel backwards.
While binoculars will only show the planet as a “star”, a small telescope magnifying around 100x reveals a tiny disk, exposing its true identity. Owners of telescopes in the 10-inch and larger range may want to seek out the planet’s two brightest moons, Titania and Oberon. Although nearly buried in Uranian glare, a night of steady air coupled with magnifications of 200x or higher will coax each into view. To find out where they are at any time on any night, launch Sky and Telescope’s Uranus Moon Finder.
Close-up photos taken by the Voyager 2 spacecraft during its January 1986 flyby of the planet showed mostly a bland blue sphere, but Uranus is anything but boring. Here are 8 fast facts to help illuminate this faraway world:
- Twice as far from the sun (1.8 billion miles) as the planet Saturn. If you could fly there in a transcontinental jet cruising along at 550 mph, it would take 373 years to arrive. Even Voyager 2 needed 8 1/2 years to make the journey.
- Its axis is tilted 98°, so Uranus orbits the sun on its side with its poles periodically facing Earth.
- Uranus looks blue because methane in its atmosphere absorbs red light. While its atmosphere is primarily hydrogen and helium, it has more methane than Jupiter or Saturn.
- Uranus is the first planet discovered with the telescope. English astronomer William Herschel stumbled across it with his homemade 6.2-inch reflecting telescope on March 13, 1781.
- Each season on Uranus lasts 21 years. Due to its sideways rotation, each pole is plunged into complete darkness for 21 years of every orbit around the sun. Brrrr!
- Uranus is an “ice giant”. Eighty percent of the planet’s mass is made up of a hot, dense fluid of water, methane and ammonia with a rocky core at center.
- The average temperature is -350°F (-212°C) compared to clement Earth’s 61°F (16°C) average.
- A day on Uranus lasts 17 hours and 14 minutes, hardly enough time to eat, sleep, work and do the grocery shopping.