Recap

Mars: Past & Present

Monday's main guest, astronomer and author, Ken Croswell (kencroswell.com) joined guest host Barbara Simpson (email) for a discussion about Mars. Because the red planet's ancient geologic history is better preserved than Earth's, Mars could offer significant clues as to how life evolved on our planet, Croswell said.

In the past, Mars underwent "an enormous and catastrophic transition," including the loss of its atmosphere, he said, adding that Mars' smaller diameter may have contributed to its fate. Interestingly, he said that Mars' proximity to Jupiter probably prevented it from growing larger when the planets were first forming, as the larger body attracted more matter to it.

Discussing Valles Marineris, a 2500 mile long canyon on Mars, Croswell said its location lines up near where a "canal" was once detected in earlier decades. Phobos and Deimos, the two Martian moons, could serve as "natural space stations," he suggested, for missions to Mars and further out in the solar system.

Related Articles

View of Mars

This photo (click on for larger) taken by the Hubble Telescope, which shows off the Martian North Pole, is one of the images featured in Ken Croswell's book Magnificent Mars.