right ascension
right ascension — phrase
1. the astronomy value that shows how far east a star, planet, or other object lies
the astronomy value that shows how far east a star, planet, or other object lies on the sky's equator from the vernal equinox, usually written as an hour-minute-second reading
During class, Lakan copied the moon's right ascension from the sky chart.
copy right ascension from a sky chart
The app showed Mars's right ascension in hours and minutes for tonight.
right ascension in hours and minutes
Before dawn, Amelia checked Sirius's right ascension on the observatory screen.
Zayd used right ascension and declination to aim the telescope at Vega.
In the guide, the star's right ascension was printed beside a small sky map.
- RA
the standard short form used in star charts, software, and observation notes
- sky longitude
a loose teaching comparison, not the strict technical term used by astronomers
文法句型
the right ascension of + celestial body
measure right ascension in + hours
right ascension and declination
用法筆記
Usually appears with declination when someone gives a sky position. In astronomy tables, it is commonly recorded in hours, minutes, and seconds rather than in degrees.