(These dates of opposition are those of the opposition in
celestial longitude, not in right ascension.)
I took 30 [degrees] of
celestial longitude as the maximum extent of a "grouping," included the Sun and the Moon, but omitted the faint planets Uranus, Neptune, and Pluto.
The name means "division of the zodiac instrument." Jai Singh devised the Rashivalaya to permit direct observation of
celestial longitude and latitude (the angle above or below the ecliptic) of other objects as well as the Sun.
Finally the program gives the Moon's approximate
celestial longitude, which ranges from 0 |degrees~ to 360 |degrees~.
As time marches on, so does precession, which slowly shifts the stellar background eastward (parallel to the ecliptic) with respect to
celestial longitude. Thus our new star charts use the now-universal equinox 2000.0 coordinates.