What are the right ascension and declination at the vernal equinox? What about summer solstice, autumn equinox and winter solstice?

At the autumnal equinox, right ascension is 12H, and declination is 0 degrees.

During the summer solstice, the right ascension is 6H and the declination is +23.5 degrees.

In winter solstice, the right ascension is 18H, and the right ascension is -23.5 degrees.

The vernal equinox refers to one of the 24 solar terms, that is, when the sun is located at 0 degrees of the yellow meridian (vernal equinox). Gregorian calendar March 20th or March 2nd1day. At the vernal equinox, the direct point of the sun is on the equator, and then the direct point of the sun continues to move northward, so the vernal equinox is also called the "ascending equinox".

In ancient times, it was also called "Japan-China", "Day and Night" and "Mid-spring Moon". The vernal equinox is an important solar term, which not only has astronomical significance: the northern and southern hemispheres are equally divided day and night, but also has obvious characteristics in climate.

At the vernal equinox, theoretically, the world is as long as day and night (see the dawn). After the vernal equinox, the days in the northern hemisphere are getting longer and shorter, and the nights in the southern hemisphere are getting shorter and shorter. At the vernal equinox, there are no extreme days and nights in the world.

After the vernal equinox, it began to be extremely daytime near the North Pole, and its scope gradually expanded. Near the Antarctic, the extreme day ends and the extreme night begins, and the scope gradually expands. ?

When the vernal equinox comes, the climate is mild, the rain is abundant and the sun is shining. Winter crops in most parts of China enter the spring growth stage, which is also the sowing time of early rice.