อภิธานศัพท์ฟิสิกส์ (อวกาศ)


อภิธานศัพท์ฟิสิกส์ (อวกาศ)
เลือกดูโดยใช้ดัชนีคำศัพท์

พิเศษ | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ทั้งหมด

U

U BURST

A fast radio burst spectrum of a FLARE. It has a U-shaped appear- ance in an intensity-vs.-frequency plot.

ULTRA HIGH FREQUENCY (UHF)

Those radio frequencies exceeding 300 MHz.

UMBRA

The dark core or cores (umbrae) in a SUNSPOT with PENUMBRA, or a sunspot lacking penumbra.

UNIVERSAL TIME (UT)

See COORDINATED UNIVERSAL TIME.

UNSETTLED

With regard to geomagnetic levels, a descriptive word speci- fically meaning that 8 is less than or equal to the Ap INDEX which is less than or equal to15.