This is Mary Tillotson.
And this is Steve Ember with the VOA Special English program EXPLORATIONS. Today we tell about the last task of the space vehicle, Galileo. We tell about the successful flight of NASA’s space shuttle Endeavour to the International Space Station. And we tell about exciting evidence of water ice on the planet Mars.
NASA has announced the best direct evidence of water ice on the planet Mars. A NASA spacecraft, the two-thousand-one Mars Odyssey, found the evidence.
William Boynton is a researcher at the University of Arizona. He is also the top investigator for one of the scientific instruments carried by the Odyssey Spacecraft. The gamma ray spectrometer can discover what is below the surface of Mars to a depth as great as one meter.
Mister Boynton is excited about the evidence produced by the gamma ray spectrometer. He says, “We were hopeful that we could find some evidence of ice, but what we have found is much more ice than we ever expected.”
Scientists used Odyssey’s gamma ray spectrometer instrument to find hydrogen, which is extremely good evidence of the presence of water ice. They found the main hydrogen evidence in the top meter of soil in a large area surrounding the south pole of Mars. Mister Boynton says it is really an area of ice that is full of dirt. It is dirty ice, not dirt that contains ice.
The amount of hydrogen discovered shows more than fifty percent ice between thirty and sixty centimeters below the surface. This means if a container of this soil was heated it might produce more than half a container of water.
This direct evidence of water ice is extremely important to future exploration of Mars. Finding water on Mars means a manned spacecraft could be launched from Earth without having to carry huge supplies of water. This would greatly cut the time and cost of planning a flight to Mars.
Stephen Saunders is the Odyssey project scientist at NASA’s Jet Propulsion Laboratory, in Pasadena, California. He says scientists have suspected for a long time that large amounts of water were present on Mars. Mister Saunders says the big questions they are trying to answer are ‘where did all that water go?’…and…’what does this water mean for life?’
NASA scientists believe this ice may have once supported life in a time when the climate of Mars was much warmer. Mister Saunders says there could still be life on Mars. He says that living organisms can be found in cold environments on Earth.
Jim Garvin is the Mars program scientist at the NASA headquarters, in Washington, D-C. He says it is important to measure and map the icy soils in the polar areas of Mars. He says NASA needs to continue searching perhaps deeper underground to find what happened to the rest of the water scientists think was once on Mars. The surface of Mars has provided good evidence that the planet was once covered by large areas of water. Now NASA wants to find it.
The two American members of the fourth crew of the International Space Station have set a new record. They returned to Earth on the American space shuttle Endeavour last week. Carl Walz and Daniel Bursch spent one-hundred-ninety-six days in space. They broke the record set by American astronaut Shannon Lucid. She spent one-hundred-eighty-eight days in space when she lived on the Russian space station, Mir, in nineteen-ninety-six.
NASA did not plan for the two Americans to break for the record for a single stay in space. But delays caused by rain at Cape Kennedy in Florida postponed the planned launch of the Endeavour. And bad weather again at Cape Kennedy forced the landing to be postponed for three days. Endeavor finally landed at Edwards Air Force Base in California last Wednesday. The space shuttle also returned to Earth Cosmonaut Yury Onufrienko (yoory oh-NEW-free-ehn-kaw) who was the third member of the space station crew.
Endeavour carried into space the fifth crew that will live and work on the International Space Station. The new crew members are Russian cosmonauts Valeri Korzun (vah-LARRY koor-ZOON) and Sergei Treschev (sehr-GAY TRESS-chev), and American astronaut Peggy Whitson.
The Endeavour also carried to the space station more than two tons of supplies and experiments in a device built in Italy. The device is called the Leonardo Multi Purpose Logistics Module. It is similar to a truck that carries supplies.
The module was carried inside Endeavour until the shuttle reached the space station. It was then taken out of the Endeavour’s cargo space and linked to the space station.
The crews of the Endeavour and the space station unloaded the experiments and supplies from Leonardo into the space station. Leonardo then was filled with completed experiments and equipment no longer needed on the station. Leonardo returned to Earth in Endeavour.
Endeavour also carried to the space station a new device called the Microgravity Science Glovebox. The European Space Agency designed and built it.
The Glovebox is an airtight container or box. Space station crewmembers can reach inside this closed box by using two rubber gloves that are built into its plastic front.
This lets them to do work with materials inside the box yet have their hands and the space station’s environment protected at the same time. The front of the box is clear plastic so the crewmembers can see inside.
The Glovebox is a safety device. It lets the crewmembers do science experiments involving dangerous fluids, chemicals, flames, and gases. The Glovebox is designed to stay in the space station for ten years.
The Space Shuttle Endeavour also carried the equipment needed on the space station to complete the Canadian Mobile Service System. The Mobile Service System uses a huge mechanical arm to move and lift objects from one place to another on the space station.
The Mobile Service System is really a large tool. One of its main purposes is to link new parts of the space station when they arrive. The large arm can move to different parts of the space station on something similar to a railroad track. Shuttle crewmembers worked outside the shuttle to complete this track.
Although the American record for longest single stay in space was broken, Russian Valery Polyakov is still the all-time record holder. Cosmonaut Polyakov spent four-hundred-thirty-eight days on the Mir space station in nineteen-ninety-four and ninety-five. Astronauts Carl Walz and Daniel Bursch said they would not want to try to break that record. They said they were ready to come home.
NASA’s Galileo spacecraft has sent back new pictures of Jupiter’s moon, Io. Taking photographs of Io was Galileo’s last task.
Galileo was launched from the space shuttle Atlantis in nineteen-eight-nine. The spacecraft flew by Venus, Earth and two asteroids on its way to Jupiter. It has been in orbit around Jupiter since December, nineteen-ninety-five. Scientists planned for Galileo to orbit Jupiter for two years. But it has survived as a successful scientific instrument now for more than six years.
Galileo flew more than thirty times near Jupiter’s four largest moons. It found evidence for liquid saltwater on the moons Europa, Ganymede and Callisto. It found volcanoes on the moon Io.
Galileo found more volcanoes during its last flight near Io. It has found evidence of more than one-hundred-twenty volcanoes on Io and taken pictures of seventy-four of them.
Galileo has returned to Earth about fourteen-thousand photographs of Jupiter and its moons. It will soon pass through an area of extreme space radiation near Jupiter. It will also fly near the moon Amalthea for the first time in November.
NASA says it has no plans at this time for Galileo to take photographs of Amalthea. NASA officials say the fuel used to control the space vehicle is almost gone. They say Galileo will pass Amalthea and circle one last time away from Jupiter. Then it will turn back and fall into Jupiter’s atmosphere. Galileo will be destroyed by Jupiter’s atmosphere in September, two-thousand-three.
This Special English program was written by Paul Thompson and produced by Cynthia Kirk. This is Mary Tillotson.
And this is Steve Ember. Join us again next week at this time for another EXPLORATIONS program on the Voice of America.