The equatorial coordinate system projects Earth's latitude and longitude onto the celestial sphere, using declination (angular distance from the celestial equator, measured in degrees) and right ...

The autumn equinox is now upon us! Today marks the moment that the sun crosses the celestial equator, ushering in the beginning of astronomical autumn in the northern hemisphere, which brings with it ...

As someone who has spent thousands of hours observing the night sky, I like to think that I’m pretty familiar with it and able to navigate my way around with some ease. That’s certainly true on the ...

Astronomical fall begins on Sept. 22 as the sun moves southward across the celestial equator. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works.