How Long is a Day on Neptune?
Rotation of Neptune. Image credit: Hubble
[/caption]
A day on Neptune is 16 hours, 6 minutes and 36 seconds.
Wait, not so fast! Here’s the problem. Neptune isn’t a single solid object like the terrestrial planets, so different parts of the planet rotate at different speeds. This is a process that astronomers call differential rotation. Neptune’s equatorial zone takes about 18 hours to complete a rotation – that’s slower than the planet’s averate 16.1 hour rotation period. And the polar regions can take just 12 hours to rotate; much more quickly than the average.
This big difference in rotational rate between the equatorial regions and the planet’s poles means that Neptune has a strong latitudinal wind shear. This helps to generate the strongest winds in the Solar System. Astronomers have clocked winds on Neptune going as fast as 2,400 km/hour (1,500 miles/hour).
We have done several stories about Neptune on Universe Today. Here’s an article about movies of Neptune captured by Hubble. These show its rotation.
If you’d like more information on Neptune, take a look at Hubblesite’s News Releases about Neptune, and here’s a link to NASA’s Solar System Exploration Guide to Neptune.
We have recorded an entire episode of Astronomy Cast just about Neptune. You can listen to it here, Episode 63: Neptune.
Recent Posts
Can Entangled Particles Communicate Faster than Light?
Entanglement is perhaps one of the most confusing aspects of quantum mechanics. On its surface,…
IceCube Just Spent 10 Years Searching for Dark Matter
Neutrinos are tricky little blighters that are hard to observe. The IceCube Neutrino Observatory in…
Star Devouring Black Hole Spotted by Astronomers
A team of astronomers have detected a surprisingly fast and bright burst of energy from…
What Makes Brown Dwarfs So Weird?
Meet the brown dwarf: bigger than a planet, and smaller than a star. A category…
Archaeology On Mars: Preserving Artifacts of Our Expansion Into the Solar System
In 1971, the Soviet Mars 3 lander became the first spacecraft to land on Mars,…
Building the Black Hole Family Tree
Many of the black holes astronomers observe are the result of mergers from less massive…