Autumn Equinox

Autum Equinox 2019 Girl-01Do you know that our Earth actually rotates on a tilted axis? Earth rotates by itself around a fixed axis called the rotational axis. At the same time, Earth also orbits around the Sun in a fixed axis called the orbital axis. The rotational axis is not actually perpendicular to the orbital axis. As the result, our Earth is tilted to a certain angle compared to its orbital axis. And the celestial equator, the imaginary line in the sky above Earth’s equator, is also tilted to a certain angle compared to Earth’s orbital axis. Continue reading