EXPLORATIONS - Space Digest
By Paul Thompson
Broadcast: Wednesday, March 03, 2004
This is Faith Lapidus.
Millions of people have seen pictures like this on NASA's website.
And this is Steve Ember with Explorations in VOA Special English. Today we tell the latest news from the International Space Station. We tell about new evidence of a black hole, one of the most powerful objects in space. We report about problems that must be solved before people can be sent to the planet Mars. We begin our report with news about the two vehicles that are now exploring that planet.
The National Aeronautics and Space Administration has set a new record. On February nineteenth, NASA reported it had received more than six-thousand-million "hits" to its Internet Web site. A hit is recorded for every piece of information a computer user receives from a Web site. All of these hits were to see the NASA photographs taken by the two Mars exploration vehicles, Spirit and Opportunity.
Glenn Mahone is the assistant administrator for NASA. He says this huge number of hits makes this the biggest Internet event in the history of the United States government. Mister Mahone says it could be the biggest single Internet event in history by the time the Mars rovers' ninety-day exploration is completed.
NASA says its Web sites have recorded at least one hit for every person on Earth since the first rover landed on Mars at the beginning of January. Public excitement about the Mars exploration was immediate. NASA says there were two-hundred-twenty-five-million hits within the first twenty-four hours after Spirit landed. NASA says the huge number does not really represent that many computers.
NASA officials say they believe about fifty-million individual computer users around the world have linked with NASA many, many times. Some of the computer users move from page to page within NASA's Internet Web site. Each of these movements counts as a hit. That is the reason the number of hits is so large. NASA says many people are following the daily progress of the two rover vehicles with the aid of the Internet.
What are all of these people seeing on the Internet? They are seeing the thousands of photographs taken by the two vehicles. And, they are reading the reports NASA releases about the exploration rovers.
For example, a recent photograph shows Spirit's mechanical arm lowered into a long hole the rover dug in the surface of Mars. Scientific instruments on the arm are inspecting soil and rocks.
The Opportunity rover is doing similar work on the other side of the planet. It is also inspecting soil. It has found strong evidence that water may have been extremely important in the ancient history of Mars.
If you would like to follow the progress of the two vehicles and can link with the Internet, type the letters WWW.NASA.GOV and follow the links that are provided.
All the recent excitement about Mars has again raised the question: When will people be able to visit the Red Planet? NASA scientists are working on one of the major problems that must be solved before such a trip can take place. The problem is the extreme amounts of radiation in deep space.
Frank Cucinotta works with NASA's Space Radiation Health Project at the Johnson Space Center in Houston, Texas. Mister Cucinotta says scientists know how much radiation is out in space. However, they are not sure how it will affect the human body.
NASA measures radiation danger in amounts that create a risk of causing cancer. For example, a healthy forty-year-old American man has a twenty percent chance of dying from cancer.
That is the risk for a man who stays on Earth. The risk increases if he travels to Mars. The main problem is that scientists do not know how much the risk increases.
Mister Cucinotta says the risk for women is even greater because female breasts and ovaries can be harmed by radiation. He says the risk of cancer is almost two times greater for women than for men.
Mister Cucinotta says NASA does not want to send astronauts to Mars and have them come home only to die of cancer. He says the Space Radiation Health Project is working on different methods to protect astronauts while they make the long trip to Mars. He says experiments with some kinds of plastics show they offer better protection from radiation than the metal aluminum that is found in spacecraft.
Mister Cucinotta says the Health Project is working with a very light and strong plastic that provides twenty percent more radiation protection than aluminum. He says plastic could become the choice for building a space craft that will go to Mars.
Mister Cucinotta believes that people can travel safely to Mars sometime in the future. He says scientists must find out how much radiation our bodies can stand and what kind of spacecraft we need to build.
A picture of a black hole taken with the Chandra and X-MM Newton X-Ray space telescopes.
Scientists have long suspected that one of the most powerful objects in space is a black hole. Black holes create huge amounts of gravity. The gravity produced by a black hole is so strong it can even capture light. Black holes pull everything into them. Recently, NASA experts released information and a photograph that shows a black hole slowly destroying a star.
The powerful gravity of the black hole is tearing the star apart. Observations from two x-ray telescopes show evidence of this.
The telescopes are NASA's Chandra and the European Space Agency's X-M-M-Newton X-Ray. They were combined with earlier images from the German Roentgen Satellite. Scientists have been observing the black hole for more than ten years.
Stefanie Komossa works at the Max Planck Institute for Extraterrestrial Physics in Germany. She is the leader of an international team of researchers. Mizz Komossa says stars can bend or be stretched a small amount. However, evidence shows this star has been stretched so far it is now breaking apart. She says the star moved too close to the black hole.Scientists say the black hole they are observing has a mass of about one-hundred-million times that of the Sun. They believe the star that was destroyed was about the same size as the Sun. The black hole and the star are in a galaxy about seven-hundred-million light years away from Earth.
Michael Foale takes a walk outside the International Space Station.
Last week, for the first time, both crewmembers of the International Space Station left the safety of their home. After preparing their safety equipment, American Astronaut Michael Foale and Russian Cosmonaut Alexander Kaleri opened the door and stepped into space.
This was the first time there was no crewmember inside who could take immediate action if equipment inside the station failed.
The two crewmembers were expected to spend about six hours working outside of the space station. However about half-way through, Russian Cosmonaut Kaleri reported a problem with his space suit. At first he said he was becoming very warm.
Then he told Russian Mission Control in Moscow, "It is amazing. I have rain inside the helmet." Russian space officials called a halt to the spacewalk and ordered both men back inside the Space Station.
The spacesuit's cooling system caused the problem. The system is supposed to take water out of the atmosphere of the suit. It failed. Once back inside
the Space Station, the two crewmen inspected the spacesuit.
The men quickly discovered a bend in the tube that provides water to cool the suit in the area of the stomach. Cosmonaut Kaleri straightened the tube and it began working correctly.The two crewmen were able to complete about half the planned work before they returned to the Space Station. They replaced devices that study the lack of normal gravity. They placed a special device which will provide information on how radiation affects the human body during space flight.
They also worked with several devices that are part of an experiment by the Japanese Aerospace and Exploration Agency. This experiment studies the effect of small meteors hitting the research device. The work they were unable to complete may be performed in the future.
This Special English program was written by Paul Thompson. It was produced by Mario Ritter. This is Steve Ember.
And this is Faith Lapidus. Join us again next week for another EXPLORATIONS program on the VOICE OF AMERICA.