¡SkyCaramba! Weekly astronomy blog for October 4 to 10, 2015
You have all night to try to see Uranus. The distant blue world is at opposition on October 12. The distant and dim blue world is close to the southern fish in Pisces. Do not confuse the use of “southern fish” here with the separate constellation Piscis Austrinus or you’ll never find Uranus!
Uranus will be just a little less than 19 astronomical units from us on October 12. That’s the same thing as saying almost 19 times the distance from the earth to the sun. It’s about 2,840 million kilometers. It takes Uranus 84 years to orbit the sun.
The planet has 13 rings and about 27 moons. The material making up the rings ranges in size from fine dust to boulders about ten meters wide.
Depending on how you choose to look at the situation, Uranus has an axial tilt of 89° and it rotates backwards (clockwise as viewed over the north pole) or it has an axial tilt of 91° with normal (counterclockwise) rotation.
Unfortunately, there isn’t a brighter object near Uranus to make it easy to find and identify. But here are some tips and a map to guide you. Uranus is barely visible to the naked eye. A dark sky is essential to seeing it that way though. If you have some light pollution where you are, or if you try to see Uranus when the moon is up, you may still be able to see it with a telescope or binoculars. Using planetarium software can help you find the planet. Longtime readers of SkyCaramba have seen the free program Stellarium recommended here.