Steve Desch

Solar system swap: Uranus and Neptune switched places

Quick: What's the order of the planets in the solar system? It's Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto, right? That's right today. But four billion years ago, Uranus and Neptune switched places. How do we know? With the help of a very Nice model, for starters. --by Nikki Staab

Office of the Vice President for Research & Economic Affairs
Fulton Center, 3rd Floor: 300 E University Drive. | PO Box 877205, Tempe, AZ 85287-7205
Phone: 480-965-1225 | Fax: 480-965-8293 | Site contact