What is the constellation of 300 degrees of the yellow meridian?

Aquarius. The longitude of the ecliptic refers to the longitude in the coordinate system of the celestial sphere, measured from vernal equinox to the east, with degrees ranging from 0 to 359 degrees. In the ecliptic coordinate system, the celestial sphere is evenly divided into two hemispheres by the equatorial plane of the sky. The ancients called the annual apparent motion line of the sun (that is, the reflection of the earth's orbit on the celestial sphere) the ecliptic, with a constellation every 30 degrees, totaling 12 constellations. These twelve parts are called the zodiac. Aquarius is the 1 1 th constellation of the ecliptic 12, Uranus is the ruler and Leo is the relative constellation.