The planet Neptune has reemerged into view in the pre-dawn sky. The distant ice giant was visible in the evening sky in late 2014 before reaching conjunction with the Sun at the end of February 2015. The planet has slowly emerged from the dawn glow in the constellation Aquarius just a few degrees west of the 4th-magnitude star Hydor (lambda Aquarii). Slooh will host a live show on May 23, 2015 to celebrate the return of Neptune in time for the summer observing season.
At a distance of more than 3 billion miles from Earth, the planet Neptune never gets very bright and cannot be seen with the unaided eye. It’s an easy sight in binoculars or a small telescope, and high magnification shows Neptune as a tiny pale blue-green disk. Keen-eyed observers with large backyard telescopes can see Neptune’s largest moon Triton. While few details are visible on the planet from Earth, the Voyager 2 spacecraft in 1989 showed the face of Neptune to have a rich tapestry of features including giant oval storms and high-altitude ammonia clouds set against a rich azure background. The color of Neptune results from traces of methane and other molecules in the atmosphere that absorb red light while passing green and blue. Because the planet generates more heat in its interior than Uranus, Neptune has far more active weather than its fellow ice giant.
Join Slooh astronomers for a live look at Neptune through our remote telescopes during our show on the night of May 23, 2015, or the early morning of May 24th, depending on your time zone.