Saturn is below Venus and very low in the predawn sky. In late April it is five degrees above the horizon. You may need ...

A century ago, Edwin Hubble revolutionized our understanding of the universe by proving that the Milky Way is just one of many galaxies in an ever-expanding cosmos. This breakthrough led to the ...

Vivian Poulin asks if the tension between a direct measurement of the Hubble constant and constraints from the early universe ...

The Hubble Space Telescope captured an image of a spiral galaxy, NGC 4900, and a nearby star in the constellation Virgo. Despite appearing close, the star is 7,109 light-years away, while the ...