- 行业: Aerospace
- Number of terms: 16933
- Number of blossaries: 2
- Company Profile:
The Executive Branch agency of the United States government, responsible for the nation's civilian space program and aeronautics and aerospace research.
A measure of electrical power equal to potential in volts times current in amps.
Industry:Aerospace
A vector quantity whose magnitude is a body's speed and whose direction is the body's direction of motion.
Industry:Aerospace
Literally means "above violet" radiation. Electromagnetic radiation in the neighborhood of 100 nanometers wavelength.
Industry:Aerospace
The world-wide scientific standard of timekeeping. It is based upon carefully maintained atomic clocks and is highly stable. Its rate does not change by more than about 100 picoseconds per day. The addition or subtraction of leap seconds, as necessary, at two opportunities every year adjusts UTC for irregularities in Earth's rotation. The U.S. Naval Observatory website provides information in depth on the derivation of UTC.
Industry:Aerospace
Also called Zulu (Z) time, previously Greenwich Mean Time. UT is based on the imaginary "mean sun," which averages out the effects on the length of the solar day caused by Earth's slightly non-circular orbit about the sun. UT is not updated with leap seconds as is UTC.
Industry:Aerospace
Downlink power amplifier in a spacecraft telecommunications subsystem, the final stage of amplification for downlink (same unit as TWT).
Industry:Aerospace
Downlink power amplifier in a spacecraft used to amplify radio frequency signals to high power, usually in an electronic assembly known as a traveling-wave tube amplifier (TWTA). Telecommunications subsystem, the final stage of amplification for downlink (same unit as TWTA).
Industry:Aerospace
Describing a spacecraft's downlink is not based upon a received uplink from DSN.
Industry:Aerospace
