|
see with the unaided eye. The dwarf planet Pluto isn't visible to the unaided eye, either, by the way. Neptune shines quite close to the border of the constellations Aquarius and Capricornus now. It's also close to the ecliptic - the path the planets follow in front of the constellations of the Zodiac. Because of the moonlit glare, you probably won't see either Aquarius or Capricornus tonight. What will you see? Only the moon shining in all its splendor. You can gaze at it and imagine Neptune nearby.
• Although the moon and Neptune are close together on the sky's dome tonight, they're nowhere close in space. The moon resides about 1.3 light-seconds from Earth, whereas Neptune looms way out there at over four light-hours away. In other words, Neptune is over 11,000 times farther away than the moon in tonight's sky.
• Once the moon leaves the evening sky, starting in early December, Aquarius and Capricornus will easy to spot in a dark country sky. Then, if you're armed with a telescope or powerful binoculars, you might be able to glimpse Neptune.
• For another stellar reference, Neptune resides some two degrees from the dim yet visible fourth-magnitude star Iota Aquarii. (The width of your little finger at an arm's length approximates the spacing between Neptune and the star Iota Aquarii.) But Neptune demands high-quality binoculars or a telescope, patience and a detailed star chart. For the rest of the year, Neptune will be found about two degrees from Iota Aquarii, with the two readily taking stage within the same binocular field.
• Bottom line: On this November night - November 20, 2012 - use your mind's eye to envision the solar system's most distant major planet - Neptune - by tonight's waxing gibbous moon.
•
|
|
