Are you getting sick of Earth and all its petty little squabbles? Maybe you're thinking it's time to find a new planet upon which you and your progeny can frolic free of polluted lakes and hazy air?

	The dark ring in the foreground surrounds the central mountain peak of the 81-mile crater Herschel on Saturn's moon Mimas. This is among the images in "The Grand Tour: A Traveler's Guide to the Solar System" by William K. Hartmann and Ron Miller. Click photo for larger image.

You should check out Io. It's one of Jupiter's moons, where there are volcanoes more active than Mount St. Helens. Or look to Saturn's moon Enceladus, where a sea of water might exist below a giant sheet of ice. And there's always the old standby of Mars, hot interplanetary real estate where there once was water and could still be some forms of life.

Pittsburgh native William K. Hartmann wants to be your real estate agent. In his new book, "The Grand Tour: A Traveler's Guide to the Solar System," co-authored with longtime collaborator Ron Miller, the astronomer paints a picture of the planets and moons that are our neighbors, sharing recent discoveries and historical stories. It's part glossy travel book, part history lesson, part encyclopedia that covers more than the nine planets. In fact, if there's one thing we learn from Hartmann's book, it's that the old mnemonic to remember the planets' order, My Very Educated Mother Just Served Us Nine Pancakes, is outdated -- for today's solar system is a virtual alphabet of planets, moons, satellites and activity.

Hartmann grew up in New Kensington, where he first watched the stars through a homemade telescope in his back yard. He went on to Penn State, and left there in 1961 for graduate school in Arizona, where he still resides.

It was the right time to be delving deep into outer space. In 1957, the first satellite orbited the Earth, followed closely by the first dog in space. Then Yuri Gagarin went to space in 1961, and man landed on the moon in 1969 (unless, of course, you believe the conspiracy theories that argue otherwise).

William K. Hartmann Click photo for larger image. Lecture and book signing The Carnegie Science Center's Buhl Planetarium will host William K. Hartmann for a lecture and book signing Wednesday at 7 p.m. Tickets are $25 and include a copy of "The Grand Tour: A Traveler's Guide to the Solar System." For more information, call 412-237-3400.

Hartmann was involved in some of these early expeditions, including a moon mapping project to draw the dark side of the moon, and a planning team for the first Mars mission in 1971. But since the early days of planetary studies, astronomers like Hartmann have discovered other fascinating facts about the solar system, which he documents in his book.

For instance: the greenhouse effect on Venus has been trapping infrared radiation in the atmosphere for millions of years, which might be a useful warning about how planetary gases operate. And Europa, a satellite of Jupiter that is almost 800 million kilometers from the sun, is warmed by gravity and has a giant ice ocean.

He talks about recent discoveries, too. American rovers on Mars discovered sedimentary rocks last year, which are different from the volcanic lava previously found there. This indicates that Mars had lakes or seas, and that early Mars was similar to early Earth, Hartmann said. If early Mars and early Earth were the same, and if life started here, he wonders, did it start there?

"If we find fossils of bacteria, we're not alone in the universe," he said. "But if no life ever started there, that's pretty profound, too."

He speculates that we will know if there was life on Mars by the year 2020.

But Hartmann doesn't study space just for the sake of doing so.

"We see that petroleum reserves are running out, but solar energy is flowing through space," he said. NASA is building solar panels to harness some of that energy, and Hartmann said that alternative energy sources like those will be essential in the future.

To those who say that we should be spending our money down here on Earth rather than out in space, Hartmann argues that it will be important to think in the long-term about finding ways to conserve our planet by looking at others. He sometimes worries that the anti-science fundamentalists in our country and around the world are endangering the future of space exploration and thus of our own planet.

But practical stuff aside, part of Hartmann still likes to mull over the "big picture" questions that space study raises. He can't wait to find out if we're alone in the universe and how humans came to be here on Earth.

Early in his career, Hartmann thought about becoming an astronaut, but decided that his skills and talents could be better served on the ground, by helping plan missions for others and showing Earthlings about the giant galaxy in space.

Now that he has an asteroid named after him (No. 3341), has written numerous books about space and evolved into a space artist as well, he's pretty sure he made the right decision. His form of space travel works well for him too.

"I travel to other planets," he said, "only in my imagination."