[by:www.51voa.com] [00:00.00]更多听力请访问51VOA.COM [00:00.88]The video of the massive SpaceX rocke [00:05.72]t landing safely back on Earth [00:09.16]was like the take-off, but in reverse. [00:13.44]The rocket is called Falcon 9. [00:16.68]And the safe landing is a big deal. [00:20.52]It means that space travel could become a lot easier in the future. [00:26.72]Normally rockets deliver their payload [00:31.20]– a satellite, for example, or supplies [00:35.32]– and then burn up on their way back to Earth. [00:38.68]What the SpaceX mission proved Monday night [00:42.44]is that a rocket may be able to safely return to Earth and be used again. [00:49.16]The successful landing is even more notable [00:53.84]considering a similar rocket failed when it launched six months ago. [01:00.24]The way it works is that the entire rocket unit leaves Earth's atmosphere, [01:06.24]and then the 15-story-tall rocket booster separates, flips [01:11.80]and comes back to a landing zone six miles away. [01:16.64]If the rocket booster can be used again [01:19.60]it means the cost of entering space can be significantly reduced. [01:24.36]For example, similar boosters cost $60 million to build, but are only used once. [01:31.76]If SpaceX is a success, it will cost $60 million once, [01:38.20]and then future missions will only include the cost of repairs and fuel. [01:44.40]The owner of SpaceX is businessman Elon Musk. [01:49.16]He also owns the Tesla electric car company. [01:54.84]A company called OrbComm hired SpaceX to deploy 11 satellites. [02:01.88]That part of the mission was a success, too. [02:05.68]Musk says the success of this week's launch and return is exciting, [02:12.08]but his real goal is to send a human mission to Mars. [02:16.92]"This was a critical step along the way [02:20.44]to being able to establish a city on Mars. [02:24.68]That's what all this is about." [02:26.80]The rocket launch and landing took place in Cape Canaveral, Florida, [02:32.48]a city famous for many other successful rocket launches, [02:36.92]but none where the booster returned in one piece. [02:40.88]Observers say the test will have to be repeated several times [02:45.48]to prove that it is possible to reuse space rockets. [02:50.00]I'm Dan Friedell. [02:51.52]更多听力请访问51VOA.COM