Not Another One!

Just like its bigger siblings, Neptune is amassing more moons.  As the eighth planet from the sun and, according to the AIA, the last planet in the solar system (insert Pluto for Planethood chanting here).

Neptune is also the 4th largest planet in the solar system behind Jupiter, Saturn and Uranus.  With a mass 17 times greater than the Earth, it is no wonder that smaller bodies passing by have been caught in its gravity well.

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Neptune was the first planet found by mathematical prediction rather than by direct observation. Changes in Uranus’s orbit led French mathematician and astronomer Alexis Bouvard to deduce that Uranus’ orbit was being effected by gravitational forces from an unknown planet.

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Using Bouvard’s astronomical tables of Uranus, the orbit of Neptune was calculated by Urbain Le Verrier.


Neptune was observed for the first time on September 23, 1846 by Johann Galle less than a degree from the position calculated byLe Verrier.  This is actually quite a feat considering the telescopes of the era.  Even today, Neptune is a hard target to find.

Neptune is also famous for one of its moons, Triton.  Triton It is the only large moon in the Solar System with a retrograde orbit (an orbit in the opposite direction to its planet’s rotation).  So Triton is probably a captured planet/moon (make up your mind IAU!).

Triton has a new sibling.  Well, not that new.  The newly discovered moon (Neptune’s 14th) has been designated as S/2004 N 1, until a real name is selected, is about 12 miles in diameter.  This would make it the smallest known moon in the Neptunian system.  It is so dim that it is roughly 100 million times fainter than the faintest star that can be seen with the naked eye.

It is so dim that Voyager 2 missed it during a flyby in 1989.  This is even more amazing because Voyager 2 was specifically looking for moons.

I can hardly wait for the naming games to begin.

– Ex astris, scientia –

I am and avid amateur astronomer and intellectual property attorney in Pasadena, California and I am a Rising Star as rated by Super Lawyers Magazine.  As a former Chief Petty Officer in the U.S. Navy, I am a proud member of the Armed Service Committee of the Los Angeles County Bar Association working to aid all active duty and veterans in our communities. Connect with me on Google +