Science
| By : Gurpreet Kaur | Previous | Next |
| Posted on : 02 Sep, 2005 | Total Views : 270 |
ELECTRONICS 6
Electronics in Project Apollo
Man's first trip to the moon via the U.S. Apollo spacecraft represents a massive challenge to the electronics industry. Complex, highly sophisticated systems are being built, tested, and installed to accomplish such critical functions as stabilization, guidance and navigation, and communication. There will be little room for error or failure in any one of these electronic systems, each of which is densely packed with hundreds of thousands of electronic components.
Electronics will play several roles in the lunar mission. Guidance and control of the Saturn booster stage during blast-off will be handled by a combination of a ground-based computer and an electronic system housed in the second stage of the booster. Once the craft is in orbit around the earth, sensitive receivers and high-gain antennas at tracking stations throughout the world will keep contact with the space vehicle. Precise position information will be transmitted to the astronauts for insertion in their space-borne guidance computer. Information from the computer will determine the precise timing and duration of the booster refiring, as well as the exact attitude and position at the time of the refiring, to hurl the craft out of the earth's pull toward the moon. The astronauts and ground stations will then quickly compare guidance data to assure proper trajectory. Another group of electronic systems will aid in spacecraft control, positioning of the Command and Service Module (CSM) relative to the Lunar Excursion Module (LEM)—the vehicle which will descend to the moon—and midcourse corrections. After two of the astronauts have descended to the lunar surface in the LEM, leaving the CSM in orbit about the moon, rendezvous between the CSM and LEM is accomplished with the help of tracking radar. The two astronauts return in the LEM to join their companion in the CSM. The LEM is detached and left in a lunar orbit. Headed back to earth, the vehicle again depends on precise guidance and control exercised by electronic systems. The dangerous and critical phase of re-entry first involves precise control: If the vehicle enters the atmosphere at a shallow angle, it will bounce off the atmosphere and disappear into space; if entry is at too sharp an angle, the vehicle will burn up.
