This program, called Equinoxes and Solstices (whose over-long name is Equinoxes and Solstices and Cross-Quarter Days) is a tool to precisely calculate the times and dates of Equinoxes and Solstices and Cross-Quarter Days (those days which are approximately between a solstice and an equinox).
For example, in a Northern hemisphere observatory it falls just half way between the Winter Equinox and the Spring Solstice. Equinoxes and Solstices calculates all the data in a few minutes.
In Equinoxes and Solstices you can make searches for any year, and for different time zones around the world.