URANUS AT OPPOSITION THIS WEEK: NOW IS THE TIME TO VIEW THIS ICE GIANT.
Photo By: NASA/ Voyager 2 (CLICK of photo for full size and see below for related links).
Thursday, October 3, 2013 at exactly 1358 UTC (0958 EDT) the Ice Giant Uranus reaches opposition. The location will be in the constellation Pisces. Like the opposition of Neptune in August this doesn’t mean a whole lot in the way of resolution and believe me the exact time posted above is just a formality as you can probably go out tonight and view it and then again while it’s at opposition and literally not see much of a difference.
We are 1AU from the Sun (About 93 million miles) while Uranus will be a distant 19AU from the Sun at the time of opposition. Best viewing is anytime really but on the surrounding opposition nights it will reach its highest point in the night sky around midnight wherever you are, shining at a naked eye magnitude of about 5.7 though at an angular size of 3.7” arcseconds, it will look like a faint star at best (1-arcsecond = 1/3600th of ONE degree of night sky). The mechanics are similar to a Full Moon as it is opposite the Sun, Uranus will be highest in the night sky when the Sun is at its lowest point below the horizon and will set approximately as the Sun rises. Every night after opposition Uranus reaches its highest point approximately four minutes earlier.
Let’s take a quick look at definitions for a moment just to clarify a couple of points. Opposition is when the Earth is placed exactly between the Sun and a given superior planet (Planets beyond Earth’s orbit) with Earth and said planet on the same side of the Sun. Because planetary orbits aren’t perfect circles, opposition doesn’t truly mean “closest point” to Earth. The term “perigee” (Yep it’s not just a term for the Moon) still applies here and they indeed happen at different times though very close.
As a baseline Uranus reaches opposition every 369.6 days or about 4 days later each successive year.
NAKED EYE PLANETS data page on Uranus: http://www.nakedeyeplanets.com/uranus.htm
IN THE SKY data page of the opposition of Uranus: http://in-the-sky.org/news.php?id=20131003_14_100
NASA Voyager 1&2 where are they now?: http://voyager.jpl.nasa.gov/where/