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How Earth looks from outer space

If you were looking with the eye alone, how far away in space would our planet Earth still be visible?

Asteroid Florence found to have 2 moons

3122 Florence passed yesterday, biggest near-Earth object to pass so close in a century. Radar revealed 2 orbiting moons! Plus a chart that’ll help you spot the asteroid.

September guide to the bright planets

Jupiter and Saturn are evening planets. Venus, Mercury and Mars are morning planets. Watch for the close conjunction of Mercury and Mars around mid-September.

Capricornus? Here’s your constellation

No matter where you live worldwide, Capricornus the Sea-goat climbs highest in the sky in early September. How to see it, and how a sea-goat came to reside among the stars.

Alpha Cephei is a rapidly rotating star

While not one of the most conspicuous stars in the night sky, Alderamin – aka Alpha Cephei – is easy to spot, and is interesting for its rapid rotation on its axis.

When is the Harvest Moon in 2017?

In 2017, the autumnal equinox for the Northern Hemisphere comes on September 22. Official Harvest Moon is October 5, but the September 5-6 full moon shares the characteristics of a Harvest Moon.

Astro festivals, star parties, workshops

What could be more fun on a cool, crisp autumn evening than a star party? Find a 2017 star party near you.

Biblical signs in the sky?

Will the sky on September 23, 2017 mirror “signs” from the Book of Revelation in the Bible? An astronomer responds.

How far is a light-year?

How can we comprehend the distances to the stars? This post explains light-years in terms of a scale of miles and kilometers.

When’s the next U.S. total solar eclipse?

After the August 21, 2017 eclipse, the next total solar eclipse visible from North America will be April 8, 2024.