Control
Robotic spacecraft use telemetry to radio back to Earth acquired data and vehicle status information. Although generally referred to as "remotely-controlled" or "telerobotic", the earliest orbital spacecraft – such as Sputnik 1 and Explorer 1 – did not receive control signals from Earth. Soon after these first spacecraft, command systems were developed to allow remote control from the ground. Increased autonomy is important for distant probes where the light travel time prevents rapid decision and control from Earth. Newer probes such as Cassini–Huygens and the Mars Exploration Rovers are highly autonomous and use on-board computers to operate independently for extended periods of time.
Read more about this topic: Robotic Spacecraft
Famous quotes containing the word control:
“I have not ceased being fearful, but I have ceased to let fear control me. I have accepted fear as a part of life, specifically the fear of change, the fear of the unknown, and I have gone ahead despite the pounding in the heart that says: turn back, turn back, you’ll die if you venture too far.”
—Erica Jong, U.S. author. In an essay in The Writer on Her Work, ch. 13 (1980)
“The awareness that health is dependent upon habits that we control makes us the first generation in history that to a large extent determines its own destiny.”
—Jimmy Carter (James Earl Carter, Jr.)
“The poets were not alone in sanctioning myths, for long before the poets the states and the lawmakers had sanctioned them as a useful expedient.... They needed to control the people by superstitious fears, and these cannot be aroused without myths and marvels.”
—Strabo (c. 58 B.C.–c. 24 A.D., Greek geographer. Geographia, bk. 1, sct. 2, subsct. 8.