美国有线新闻 CNN 中国成功进行火星着陆器测试（在线收听）

Which planet is closest to Earth in terms of mass and size?

Mars, Venus, Neptune, or Saturn.

Scientists say it's Venus that's most similar in size, though its atmosphere it said to be a poisonous inferno.

OK. Now that this show is off the ground, we're reporting on a new Mars lander that China has gotten off the ground. It's not headed to the Red Planet yet. But the lander was recently tested in a part of China that said to have a landscape like that of Mars, with slopes and craters all around.

At first, the vehicle was suspended about 230 feet above the Earth. And then it hovered in the air and slowly descended until it was just a few feet over the ground. Scientists say the point of this was to test out the lander's ability to stay in the air and avoiding hitting any obstacles.

Landing safely on Mars is said to be one of the most challenging parts of any mission, even though the planet's gravitational pull is only about a third of that of Earth's.

China has invested billions of dollars into its space program. It's hoping to become a leading power in space. And it's planning to launch an unmanned Mars exploration mission next year.