The Seven Wonders of the Solar System

People like to make lists of things, especially lists of superlatives: the best, fastest, oldest, largest, heaviest and so on. There are lists of the ten fastest animals and the ten longest rivers and even of the ten highest-paid rock stars. The Guinness company created a small industry from publishing lists exactly… » 9/14/14 3:30pm 9/14/14 3:30pm

The solar system's second tallest mountain is hidden away on the weird…

The tallest peak in the solar system is Olympus Mons of Mars, three times taller than Mount Everest. But it's not as easy to say what the second tallest mountain is...but it might be found in the unlikeliest of places. » 10/05/11 7:40am 10/05/11 7:40am

Mars's Grand Canyon is as long as the United States

This is the Valles Marineris, believed to be the biggest canyon in the entire solar system. At nearly 2,500 miles long, it would stretch clear across the continental United States. » 3/27/11 9:00am 3/27/11 9:00am

The Rough Guide to Solar System Mountaineering

The great challenge for any climber is to conquer each continent's tallest mountain. But tomorrow's climbers can consider a far more extreme challenge: leaving Earth to climb the tallest peaks of the solar system. Here's how they'll do it. » 10/01/10 9:30am 10/01/10 9:30am

Biggest Crater in the Solar System Found on Mars

For a small planet, Mars sure knows how to go big. It's about half as large as Earth, but it's got the hugest volcano in the solar system in the Arizona-sized Olympus Mons and the grandest of all canyons in the 7 kilometer-deep Vallis Marineris. Now it can add its coolest, most-braggable title: the Biggest Impact… » 6/26/08 9:41am 6/26/08 9:41am