Right ascension
Also called: RA.
The sky's “longitude”, measured eastward in hours, minutes and seconds (0h to 24h).
Right ascension is measured from the point where the Sun crosses the celestial equator in March. It's counted in hours because the sky turns once a day: an object 1h further east in right ascension crosses the meridian an hour later.
In AstroPilot
Object pages give the right ascension and declination for the J2000 epoch.