Imagine you were going on a very long car trip. The first thing you would do is find out about the place you are going. You might get pictures to see what it looks like, and weather reports to see what kind of clothes to wear. You would check to see if you need snow tires on your car or four-wheel drive for bumpy roads. If you were going to another country, you might even get shots to make sure you wouldn't get sick. Once you were ready, you'd bring lots of snacks, pack the car, and go.

Going to Mars is just like going on that car trip, except that nobody's ever been there before. At NASA, we'd like to visit Mars as soon as possible, but we have a lot of learning and packing to do first.

Recently, planning for the Mars trip got a big boost. In a speech given in January, President George W. Bush announced that he wanted to send humans back to the moon—and then land astronauts on Mars by the year 2020.

First Steps

The first step was to figure out what Mars looks like. During some parts of the year, you can see Mars in the sky as a bright, red dot. If we're going to go there, though, we need much better pictures. In 1971, NASA launched Mariner 9, a spacecraft that orbited Mars and took pictures. From those images we learned that Mars had volcanoes three times larger than Mount Everest and a canyon more than 10 times larger than the Grand Canyon.

The next step was to land something on Mars that could record the weather and take pictures of the ground. In 1977, spacecrafts named Viking I and Viking II landed on Mars. They sent back analyses of the dirt and reported on the weather for almost four years.

In 1997, NASA sent Sojourner, a robot with wheels. Sojourner drove around a few feet and sent back even better pictures than Viking. This year, Spirit and Endeavor landed and drove much farther. They not only took pictures of rocks, but also scraped them and dug in the dirt around them.

Better Robots

Over the next 20 years, we are going to send more and better robots to Mars. Those robots will send back better pictures, maps, samples, and weather reports. There is a limit to what robots can tell us, though, so eventually we will have to send people to study the planet.

Before people can visit Mars, we need to invent a spaceship that can take us there. Mars is very far away. Depending on where Mars and Earth are in their orbits around the sun, it could take between six months to a year to get there.

The moon is much closer, and we were there, 25 years ago. Over the next 10 years, we are going to work on building a new spacecraft that can go to the moon. Using this craft, we will practice the skills we need to go to Mars.

Once we return to the moon, we are going to build a station so that people can live and work on the moon for months at a time. This is important so that we have a place to start from when we want to visit Mars, but it is also important because it gives us practice with living away from Earth.

By the time you are old enough to be an astronaut, we will have people spending months on the moon. By the time you are old enough to be a commander of a space mission, we will be taking trips to Mars. By the time your kids are old enough to be astronauts, we may have people living on Mars. Wouldn't it be cool to get a postcard from someone who was building a house on Mars? Wouldn't it be cooler if it was you who sent the postcard?

Salvatore Domenick Desiano is a research scientist working at the NASA Ames Research Center.