Twice each year the Earth experiences an equinox. The autumnal equinox will be Sept. 22. These are times when the sun is located directly above the equator, and the days and nights are equal lengths. This year, on that date in Houston, the sun rises at 7:12 a.m. and sets at 7:13 p.m. The exact time of the equinox is 3:21 p.m. This marks the beginning of autumn for those in the northern hemisphere.
This is all part of the normal cycles of the solar system. It is based on our location in our elliptical orbit around the sun and the Earth’s axial tilt. As the Earth orbits the sun, our axis of rotation (think the North Pole) always points to Polaris, the North Star.
The Observatory will not be open for a public night in September due to the current COVID-19 resurgence. We will evaluate the situation for future events.