It is the apparent direction from which the Meteors belonging to a certain meteoric rain seem to radiate over the celestial vault.
Because the solid corpuscles that make up the swarm of a meteoric rain, travel together along a certain orbit around the Sun in parallel paths, when the Earth intercepts them they penetrate our atmosphere showing the same radiant point. The radiant coincides with a certain point of the starry sky and usually takes the name of the constellation in which it is located.
The determination of the radiant is one of the investigations that are generally carried out by astrophiles, habitual observers of meteoric rains. It can be determined through visual or photographic observations; it is about establishing, on a celestial map, the trajectories seen or photographed of a certain number of meteors belonging to the same rain and prolonging back its point of origin: these extensions will converge, approximately, the only point of the sky that is precisely the radiant
In long-term meteor showers it is interesting to record the phenomenon of radiant displacement, consisting of a migration from the raining point as the days pass. This is due to the fact that, moving both the swarm and the Earth along its own orbits, the celestial background on which the radiant is projected changes.
|◄ Previous||Next ►|