Uranus
milhayser | July 30, 2015New measurements from NASA's New Horizons spacecraft revealed that Pluto, named for the Greco-Roman god once called Hades, is a little more swollen with ice than previously thought, making it the biggest trans-Neptunian object—more voluminous than rival dwarf planet Eris, which is nevertheless more massive. Greg Laden explains why these orbs are not considered full-fledged planets on his blog.
While Eris orbits the Sun within the 'scattered disc,' Pluto orbits in the Kuiper Belt, a collection of gravelly snowballs that Ethan Siegel says outnumber all the planets in our galaxy. The Kuiper Belt…
jhalper | May 16, 2013Have you complained about the weather recently? On the gas giants at the edges of our solar system, Uranus and Neptune, hurricane-like storm systems as big around as Earth blow 1000 km/h winds for years on end.
Voyager II image of Neptune, showing storm features. Image: NASA
But wait…What exactly constitutes weather on a giant gas planet? Here on planet Earth, there is a clearly delineated gas layer enveloping the solid/liquid layer we call home. Our weather arises from our planet’s rotation and the solar heating of its surfaces. On a rapidly-rotating gas planet (a day on Neptune is 16 hours…
esiegel | June 30, 2012"Don't go around saying the world owes you a living. The world owes you nothing. It was here first." -Mark Twain
So, you've been around a while, seen all sorts of things, and learned an awful lot about the world, solar system and Universe that we live in. But how well do you know it, really?
Image credit: NASA / Lunar and Planetary Laboratory.
To scale and in order, these are the eight planets you know so well. There are the four rocky worlds of our inner solar system: Mercury, Venus, Earth, and Mars, and the four gas giants that dominate the outer solar system: Jupiter, Saturn, Uranus, and…
esiegel | May 6, 2008(This is adapted from my public lecture, Afraid of the Dark: How We Know What We Can't See.)
Let's go back over 200 years ago, to 1781. William Herschel (left) discovered the planet Uranus, noticing that an object, as bright as a star, was actually moving relative to the other stars. The other five inner planets (besides Earth) were known for over 2000 years before that. But it was thought for a long time that Saturn was the farthest one.
But it clearly isn't; as you can see with modern telescopes, Uranus is a super-interesting planet, rotating on its side, surrounded by rings and moons.…