Astronomy Picture of the Day
Discover the cosmos!
Each day a different image or photograph of our fascinating universe is
featured, along with a brief explanation written by a professional
August 17, 1995
Neptune: Big Blue Giant
This picture was taken by the
Voyager 2 spacecraft in 1986 - the only spacecraft ever to visit
Neptune will be the furthest planet from the
Sun until 1999, when the elliptical orbit of
Pluto will cause it to once again resume this status.
Neptune, like Uranus,
is composed mostly of liquid water, methane
and ammonia, is surrounded by a thick gas atmosphere of mostly hydrogen and
helium, and has many moons and rings.
Neptune's moon Triton is unlike any
other and has active volcanoes. The nature of
Triton's unusual orbit around
Neptune is the focus of much discussion and speculation.
Tomorrow's picture: Pluto: The Frozen Planet
| About APOD
Authors & editors:
NASA Technical Rep.:
Specific rights apply.
A service of:
Michigan Tech. U.