Year of the Comet
Comet C/2011 L4 (PANSTARRS)

PANSTARRS information

Comet C/2012 S1 (ISON)

ISON information

Discover the Solar System

Tour the solar system: Neptune

Its blue hue, changing atmosphere, thin rings, and dynamic moon make the eighth planet from the Sun a captivating place for astronomers to explore.
By Bill Andrews
Neptune
Distant, deep-blue Neptune as Voyager 2 captured it in 1989.
Photo by NASA

Welcome to “Tour the solar system.” In this series, we give you an overview of the objects in our stellar neighborhood. This video focuses on Neptune, the most distant planet from the Sun.

Yes, despite the objections of fervent Plutophiles, the International Astronomical Union’s “demotion” of Pluto to dwarf planet status in 2006 means Neptune once again has become the farthest planet. It’s a distinction the planet already held for 84 years, between its discovery in 1846 and Pluto’s in 1930, and for another 20 years (1979–1999) when Pluto’s eccentric orbit put it inside Neptune’s orbit. Neptune lies about 2.8 billion miles (4.5 billion kilometers) from the Sun on average, and it’s some 31,000 miles (50,000 km) wide — about 4 times as big across as Earth. A day on Neptune lasts just over 16 hours, and a year there takes almost 165 Earth-years.

Registered User Access Registered User Access
REGISTER TODAY to become a member of Astronomy.com
Registration is FREE and takes only a few minutes to complete. Registered members get access to these great online features:
  • Participate in our forums and online community
  • Comment on articles
  • Receive our e-mail newsletter
  • Manage your account online
  • Much more!
Already registered?
Login to view this article
Login
Haven't registered yet?
Register below
Register
SEARCH SITE
Subscriber Only Access
Subscriber Only Content
Look for this icon. This denotes premium subscriber content. Learn more »
Become a Member of Astronomy.com
Register today for access to more valuable resource information.
Interact in our forums, comment on articles, receive our newsletter and much more!
Not a member?
Subscriber and Member Login
Password
Remember me