Friday, September 28, 2012

How to See Uranus in Telescopes on Opposition

The planet Uranus reaches opposition in Pisces on Saturday, Sept. 29, 2012, and will be visible all night.
CREDIT: Starry Night Software

How to see Uranus

In binoculars, Uranus is indistinguishable from a star. Look for it currently in the constellation Pisces.

Opposition night is not the best night to look for it, because the full moon will be nearby flooding the sky with light. Look for it instead tonight, or in a week’s time when the moon has moved on.

Don’t try to use Pisces to find it, because this is a dim constellation. Instead, start with the Great Square of Pegasus, a conspicuous large square of stars. This will be in the southern sky (of the Northern Hemisphere) about two thirds of the way from the horizon to directly overhead at local midnight, or in the eastern sky earlier in the evening.

Use the two stars on the left side of the Great Square, Alpheratz and Algenib, and project a line joining them down towards the horizon. At almost exactly the same distance below the bottom star you will see (in binoculars) what looks like a double star. These will be the two brightest “stars” in this part of the sky.

The star on the left (in the Northern Hemisphere) is 44 Piscium. The “star” on the right is not a star at all, but the planet Uranus. Pay close attention to the distance between these two objects, and check it again in a night or two. Uranus will have moved away to the right, the distance between star and planet increasing.

In binoculars, Uranus will look just like a star. In a small telescope with about 200x magnification, you will see a tiny blue-green disk. Uranus has 27 known moons, but these are all too tiny to be seen in a small telescope.


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