When the termination line coincides with the meridian, what is the solar term?

Only when the direct point of the sun is on the equator can the termination line coincide with the meridian. Moreover, there are only two days in a year, that is, the vernal equinox and the autumnal equinox, which are the vernal equinox and the autumnal equinox respectively.

In these two days, the sunrise and sunset time anywhere in the world (except the poles) is 6: 00 local time, local time 18.