Mercury is notoriously difficult to see from Earth, thanks to its proximity to the Sun. But on July 4, Mercury reaches its ...

Stargazers in the U.S. will find the slender form of the crescent moon roughly 20 degrees above the western horizon right at ...

Friday, July 4 Mercury reaches its greatest eastern elongation from the Sun, standing 26° from our star at 1 A.M. EDT. We’ll ...

On July 4, Mercury will reach its greatest eastern elongation from the Sun, making it visible from Earth. While not as bright ...

The Moon’s albedo is 0.136, while the Earth’s is 0.434, making the Earth 3.2 times as reflective. That figure varies of course, depending on cloud and whether you’re facing mostly ocean or land.

Felton Davis offered thousands of strangers a close-up view of the Moon and planets orbiting New York City. Now he’s passing ...

A later variation appeared in a book, titled The Discovery of a World in the Moone by John Wilkins (1614-1672), an English ...

Moon phases reveal the passage of time in the night sky. Some nights when ... is half-illuminated from our point of view. We call it "first quarter" because the moon has traveled about a quarter of ...

In the early 1600s, Dutch spectacle maker Jan Lippershey discovered that combining lenses could magnify distant objects.

The astronauts who planted their feet on the moon were outfitted in the same glaring white as a wedding dress.” ...

Rubin Observatory begins 10-year sky survey to uncover dark matter, track asteroids, and build a detailed view of our ...