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Why do robots travel places before people?

Subject Matter Expert: Donald Strayer and Jennifer Rochlis

Exploring space is exciting, yet scary. Some people argue that space exploration is too dangerous for humans. Should space explorers be human or robotic? Is there a right choice?

NASA suggests that there’s a place for both people and robots in space exploration. Astronaut Ken Bowersox has been on five space flights and logged over 211 days in space. He believes that humans and robots are both important to the study of space. According to Captain Bowersox, “There are a lot of environments where it is not safe or cost effective to send humans. There are also times when a combination of both human and machine working together can achieve the best results."

Why should robots travel to places before people do? Robots have fewer needs and can endure more hostile conditions. People need food, water, and oxygen – things that robots never need. Reduced gravity clearly affects the human body and causes the muscles and bones of space travelers to weaken. Space radiation also affects people in ways that can make them sick. Besides, it takes years to travel to the outer planets -- much too long for an astronaut’s journey.

Robots can be programmed to do amazing things, but they can only do what they have been programmed or commanded to do. Uncrewed space probes scout out places before astronauts arrive. Robotic explorers brave hostile worlds, like Venus with its temperatures of more than 482° C (900° F), high pressure, and acidic rainfall. Although the robots sent to Venus and other planets never returned to Earth, the valuable information they collected has been transmitted to Earth.

Uncrewed space probes are tools that enable astronauts and scientists to safely gather information about the planets. Understanding and using this information helps scientists prepare astronauts for their trips into space.

The human mind can analyze a situation and adjust to unexpected situations when necessary. NASA has landed three mobile robot rovers on Mars. Sojourner, Spirit and Opportunity did their jobs well – sending back amazing pictures and important information about the Martian surface, but all three rovers moved slowly across this surface. Astronauts could cover more ground and make choices while scouting, focusing their attention only on interesting and useful finds.

The Hubble Space Telescope, a space-based telescope that orbits Earth, has given us amazing pictures of objects never before seen. When necessary, humans repair and adjust the telescope. Space tools like the Hubble Space Telescope still need humans to operate and repair them.

Seeing space through robotic eyes is much different from seeing it through human eyes. The grainy black and white pictures of the moon’s surface taken during the Apollo Missions told only part of the story. The astronauts’ words helped us all feel as though we were there. Technology has advanced since we were on the moon, making images taken in space now more real than the ones taken during Apollo Missions.

And then there are the surprises of exploration that might be lost without humans. Eugene Cernan, the last man to walk on the moon, described unexpectedly finding a patch of orange-colored soil on the “shades of gray” moon. During an interview he talked about this discovery. “No one knew what it was, whether it was old soil, new soil, soil from oxidized soil, an indication of oxygen or iron ore deep from the inner surface or whatever. It didn't turn out to be what people thought it might be, but it was a major discovery. And that's why you send people.”

Robots might someday take over some spacewalking chores. NASA is working on a robot called Robonaut to handle some of the routine tasks astronauts do in space. What's different about the latest robotic astronaut is its humanoid design with a head, two eyes, arms, and five-digit hands. Astronauts inside the station, on Earth, or on lunar habitat can control the robonauts. Inside the station, astronauts will wear helmets and gloves wired to record their motions. Outside, these actions will immediately be transferred to robonaut that will perform the motions. Working together, astronauts and robots may make human space walks more efficient than we can possibly imagine.

Scientists are working on ways to program robots with forms of artificial intelligence similar to human thinking to enable robots to “learn” the best way to perform tasks. Does this mean robots in the near future will think like humans? Of course not, but by mimicking humans and learning from mistakes, robots will become more independent and more efficient. Communication between humans and robots will be easier.

There is a need for both robots and humans in space exploration. Working as a team, astronauts and robots will help us in our quest for space exploration. NASA is charting a bold new course into the cosmos -- a journey that will take humans back to the moon and eventually to Mars and beyond.

Why do robots travel places before people? Newsbreak
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