These three pictures show three newly discovered moons of Neptune!
Click on image for full size
Courtesy of the Harvard Smithsonian Center for Astrophysics

Three New Moons Found Around Neptune!
News story originally written on January 14, 2003

A team of astronomers has discovered three previously unknown moons around Neptune using ground-based telescopes bringing the total number of moons up to 11!

The three moons were very difficult to detect because they are very small, only about 30-40 km (18-24 miles) across. Also, being so far from the Sun, the three moons do not shine very brightly. In fact, your eyes would have to be 100 million times better to see them without a telescope.

The astronomers were able to pick up the faint light from the moons by taking multiple pictures with two telescopes: the Blanco telescope in Chile and the Canada-France-Hawaii Telescope in Hawaii. They digitally combined the images and were able to see points of light where the moons were located.

Before their research, only 8 moons were known to orbit Neptune. The two largest, Triton and Nereid, were discovered in 1846 and 1949 respectively. The others were discovered by the Voyager probe in 1989. Voyager II probably missed the three new satellites because they are so small and faint and they all orbit a large distance from Neptune.

According to Mathew Hollman, one of the leaders of the team of astronomers, “Tracking these moons is an enormous, international undertaking involving the efforts of many people. Without teamwork, such faint objects could be easily lost.”

Last modified January 16, 2003 by Lisa Gardiner.

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