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 | ก | ข | ค | ฆ | ง | จ | ฉ | ช | ซ | ฌ | ญ | ฎ | ฏ | ฐ | ฑ | ฒ | ณ | ด | ต | ถ | ท | ธ | น | บ | ป | ผ | ฝ | พ | ฟ | ภ | ม | ย | ร | ล | ว | ศ | ษ | ส | ห | ฬ | อ | ฮ | ทั้งหมด
A term identifying cloud-like features in the solar atmosphere. The features appear as bright structures in the CORONA above the solar LIMB and as dark FILAMENTs when seen projected against the solar DISK.
Solar activity levels with at least on high energy event (Class X Flares)
By definition, the measurement of at least 10 protons/sq.cm/sec/steradian at energies greater than 10 MeV.
Any FLARE producing significant FLUXes of greater-than-10 MeV protons in the vicinity of the earth.
QUIESCENT PROMINENCE (FILAMENT)
Long, sheet-like prominences nearly vertical to the solar surface.
A descriptive word specifically meaning geomagnetic levels such that Ap LT 8 (see Ap INDEX).
Solar activity levels with less than one chromospheric event per day
Flares with Centimetric Bursts and/or definite Ionospheric Event (SID).
Used especially in reference to the recurrence of physical parameters every 27 days (the rotation period of the sun).
RIOMETER (Relative Ionospheric Opacity meter)
A specially designed radio receiver for continuous monitoring of cosmic noise. The absorption of cosmic noise in the polar regions is very sensitive to the solar low-energy cosmic ray flux.
In the SOLAR WIND, the area of demarcation between sec- tors, which are large-scale features distinguished by the predominant direction of the interplanetary magnetic field, toward or away from the sun.
SHORT WAVE FADE (SWF)
A particular ionospheric solar flare effect under the broad category of sudden ionospheric disturbances (SIDs) whereby short-wavelength radio transmissions, VLF, through HF, are absorbed for a period of minutes to hours.
SMOOTHED SUNSPOT NUMBER
An average of 13 monthly RI numbers, centered on the month of concern.
Central Meridian Distance (CMD). The angular distance in solar longitude measured from the central meridian.