Help - Abbreviatons
eZipSky uses several abbreviations in our nightly text messages to help convey as much information as possible. Here is an explanation of commonly used abbreviations and astronomical terms:
- (1/2): text message 1 of 2
- AM: after midnight tonight
- E,W,N, or S: cardinal directions East, West, North, or South
- SW, ESE, WNE, etc: Southwest, East-Southeast, West-Northeast, etc.
- L, R: left, right
- LL, UL, LR, or UR: lower left, upper left, lower right, and upper right
- apogee: Point in a satellite's orbit (such as the moon) when it is farthest from the earth. See perigee.
- asterism: A group of stars within a constellation that form a recognizable pattern, such as the Big Dipper (part of the Great Bear constellation).
- binocs: binoculars
- conjuntion: when a planet appears from the earth to be lined up with the sun or another planet.
- const: constellation
- deg: degrees. Used to measure distances on the sky (the full Moon is about 0.5 degrees across).
- elongation: the apparent angular separation of an object from the sun
- hr: hour (time)
- ISS: International Space Station
- mag: apparent magnitude (e.g. 3rd-mag). Used to measure brightness of astronomical objects (the brighter an object, the smaller its magnitude). The brightest star in the sky is Sirius, with a magnitude of -1.46. Other bright stars include Vega, at magnitude 0.04, and Rigel, at magnitude 0.12.
- min: minutes (time)
- occult: To cover, e.g. the Moon occults a star cluster when it passes in front of the cluster.
- perigee: Point in a satellite's orbit (such as the moon) when it is closest to the earth. See apogee.
- post-: after (e.g. post-sunset)
- pre-: before (e.g. pre-sunrise)
- SMS: cell phone text message ("Short Message Service")
- retrograde: the apparent westward motion of a planet, asteroid, or comet relative to the stars.
- terminator: the day-night boundary of the Moon
- w/: with
