Add Yahoo as a preferred source to see more of our stories on Google. In 1612, Galileo Galilei looked at the sun through a telescope, drew what he saw, and observed that sunspots — dark areas near the ...

Earth rotates once in about 24 hours with respect to the Sun, but once every 23 hours, 56 minutes and 4 seconds with respect to other distant stars. Scientists call this difference crucial to ...

Many objects in space rotate. Earth completes a spin in roughly 24 hours, while Venus takes a whopping 243 Earth days. The moon's rotational period is about 27 days. The sun, it turns out, also ...