VOA慢速英语2010年-EXPLORATIONS - On Mars Day, the Red Pl（在线收听）

DOUG JOHNSON: I’m Doug Johnson.

FAITH LAPIDUS: And I’m Faith Lapidus with EXPLORATIONS in VOA Special English. Mars Day at the Smithsonian Air and Space Museum in Washington is a celebration of our solar system’s most famous planet. The event, on July sixteenth, was a rare chance for planetary scientists to share with the public the mysteries of Mars.

(MUSIC: "Mars"/Gustav Holst)

DOUG JOHNSON:Of all the planets, none has captured the world’s imagination like Mars. Its reddish color and changes in brightness over time make the planet an unforgettable sight.

In “Cosmos,” the television science series from the nineteen eighties, scientist Carl Sagan talked about some traditional ideas about Mars. Some of these ideas are from the English science fiction writer H.G. Wells’ “The War of the Worlds.” Others are from the mistaken science of Percival Lowell, the American astronomer who believed intelligent beings lived on Mars.

Wells described Martians as threatening. Lowell imagined them as the hopeful engineers of great works. Carl Sagan said that both ideas influenced the public deeply.

FAITH LAPIDUS:Today, Mars continues to excite -- not as the object of science fiction but of scientific study. Space scientists have collected a wealth of information from spacecraft that have orbited, landed on and dug into the Martian surface.
　
Crowds gathered near Mars Day exhibits in the Milestones of Flight Gallery at the Smithsonian Air and Space Museum in Washington

The Smithsonian’s Mars Day offered a chance for people of all ages to touch Mars, or at least a piece of it. Allison and Alycia from Silver Spring, Maryland, brought their children, Grace, Sam, Ryan and Emma. They heard about Mars and its geology from experts. They could see a test version of the Viking landers that reached Mars in July of nineteen seventy-six.

They also saw meteorites known to have come from the red, or reddish, planet. Eight-year-old Sam learned that the ancient description of Mars as red is not exactly right.

SAM: “ It’s actually really orangish more than it’s red and it’s also kind of brown too. It’s not really red.”

Emma is six. She found out about the volcanic activity that has shaped the surface of Mars.

EMMA: “That the closest thing to Mars—the stuff—is from volcanoes mostly.”

DOUG JOHNSON:Orbiting spacecraft have shown a huge mountain on Mars called Olympus Mons. It is over twenty-five kilometers high and the largest known volcano in the solar system. Volcanoes on Mars suggest to Sam that the same kinds of processes that take place on Earth happen on other worlds.

SAM: “You’ll find something on Earth as close to what is pretty much on Mars. Like the volcanic rocks because I actually think those are very interesting.”

Mars Day offered Allison and Alysia’s children a chance to learn more about a world that humans may set foot on within their lifetimes. Emma is already looking forward to that day.

EMMA: “There are all sorts of rovers and stuff up there that are waiting to be discovered when people go up there.”

(MUSIC)

FAITH LAPIDUS:Can a space rock be a rock star? Meet Allan Hills 84001. American scientists discovered this meteorite in Antarctica in nineteen eighty-four. But it formed on Mars long before that. Scientists believe it is more than four billion years old.
　
A piece of Allan Hills 84001

Allan Hills 84001 is as close as any meteorite comes to being world famous. Visitors to Mars Day crowded around a piece of the meteorite in the huge Milestones of Flight Gallery. They were listening to an expert who is in charge of meteorites at the Smithsonian.

CARI CORRIGAN: “I’m Cari Corrigan. I’m a geologist over at the Natural History Museum. I curate the Antarctic meteorite collection at the museum, so we have about nineteen thousand six hundred seventy-five to be, you know, really vague.”

DOUG JOHNSON:Cari Corrigan does research on meteorites from Mars and the moon. She says the best places to find meteorites are very cold or very dry places.

CARI CORRIGAN: “They fall all over the Earth, not just Antarctica, but the best places for us to find them are the deserts because they don’t get weathered and they don’t break down as easily.”

Cari Corrigan says the search for Antarctic meteorites started in the late nineteen seventies. There are about forty Martian meteorites worldwide although there may be more hidden in collections around the world.

FAITH LAPIDUS: In nineteen ninety-six, a NASA study announced the discovery of what appeared to be the mineral remains of very simple forms of life in the Allan Hills meteorite. Research has shown that these possible fossils were not formed while the rock was here on Earth. They also have been linked to the presence of liquid water.

The true nature of the mineral formations remains the subject of debate. But one thing is sure. The discoveries in the meteorite helped shape policy and exploration efforts at the United States space agency, NASA.

Mars landers and rovers were designed to look for signs of liquid water that may have flowed on Mars in the distant past. And the search for evidence of Martian life was reborn. Looking down at a piece of the famous rock, Cari Corrigan suggested its historic importance.

CARI CORRIGAN: “So we have huge programs that came from this one research project about one football sized rock.”

Allan Hills 84001 is a plain-looking rock. But, the forces and heat that transform meteors into meteorites can create beauty as well.

CARI CORRIGAN: “This one is beautiful. This is one of my favorite rocks. You can see that black stuff on the outside, it’s called the fusion crust. And that’s what forms on the rock as it comes through the atmosphere. So a tiny bit of the outside is melted and is left with this really thin glass on the outside.”

(MUSIC AND SOUND)

DOUG JOHNSON:Long lines formed near another exhibit.

(SOUND)

Children and parents waited to have a chance to work with a robot. Orbiters, landers and rovers have all been used to explore Mars. But the NASA rovers, Spirit and Opportunity, are the closest things we have to the space robots of science fiction.

The rovers were launched in two thousand three. They can think for themselves in a limited way.

Spirit and Opportunity have wheels, an arm and camera eyes. Spirit stopped operating in March. But Opportunity continues to communicate with Earth. Both have traveled across many kilometers of the Martian surface performing experiments along the way.

FAITH LAPIDUS:On Mars Day, hundreds of people waited for their chance to use robot technology. Dan Grunberg is a student at the University of Maryland. He has been working on Mars Day for four years. He supervised the two robot activities.
　
Dan Grunberg helps a young robot operator

DANIEL GRUNBERG: “I’ve always loved working with the robots. And when I first started it was a challenge working with the robots, understanding how they worked and figuring them out. But over time, we slowly got used to it and we try to make it as kid friendly as possible because kids are what we gear towards and they’re the most important people that come through.”

FAITH LAPIDUS: In one activity, children try to get a robot arm to pick up a block and place it in a cup.

DANIEL GRUNBERG: “On station one, we have robot arms. And what happens is the robots have different joints like a human arm -- one at the shoulder, one at the elbow, wrist and then a claw. The kids are able to maneuver this with a remote control. A lot of it is like a human arm or like a space arm that you might find on the international space station.”

Another robot is designed to move and turn in a way that is similar to the Mars rovers.

DANIEL GRUNBERG: “And what happens is we have mazes and the children are able to organize the robots and see if they can get them through the maze within a certain time period.”

Judging from the long lines of people, the robot activities were the most popular at Mars Day. Children and many parents were completely absorbed in the robot-assisted tasks. This shows that the robots developed for Mars have won over a new generation of explorers.

(MUSIC AND SOUND)
　
Jim Zimbelman with some of Michael Benson's works from "Beyond: Visions of Plantary Landscapes"

JIM ZIMBELMAN: “My name is Jim Zimbelman. I’m a planetary geologist here at the Air and Space Museum. And what does that mean? It means I am trained in geology, but with interests in the other planets and Mars in particular.”

DOUG JOHNSON:Jim Zimbelman shared his studies of solar system geology with the public through images. The pictures he used are part of an exhibit called “Beyond: Visions of Planetary Landscapes” by artist Michael Benson. The exhibit shows detailed and colorful images of solar system objects including Mars.

Jim Zimbelman said Michael Benson started with publicly available images from NASA. But he used computer processing to turn them into something more -- works of art.

JIM ZIMBLEMAN: “It’s all information that is out there for anybody to look at, but Michael looked at tens of thousands of images on the Web, picked the ones that he liked, got the raw data and then did the processing.”

There are a growing number of high quality images of Mars from NASA. Last week, the space agency announced the most accurate maps ever of Mars. They show surface formations as small as one hundred meters. The maps are available for the public to use, study or turn into art. But the goal is to prepare for future robotic and human visits to Mars.

FAITH LAPIDUS: This program was written and produced by Mario Ritter. I’m Faith Lapidus.

DOUG JOHNSON: And I’m Doug Johnson. You can listen to part four of the science fiction story “A Princess of Mars” on our program AMERICAN STORIES this Saturday. You can find the whole series on our website, voaspecialenglish.com. You can also find a link to images by Michael Benson. Join us again next week for EXPLORATIONS in VOA Special English