How to see the Great Square of Pegasus

It’s easy! The Great Square of Pegasus consists of 4 stars of nearly equal brightness in a large square pattern. Once you find it, you can star-hop to other well-known sights in the sky.

A darkened skyline, with smoke from a chimney blowing sideways and a single star, Fomalhaut, above.

Fomalhaut: The loneliest star

It’s also sometimes called the autumn star for us in the Northern Hemisphere. In its large dark patch of sky, only Fomalhaut shines brightly. Here’s how to see it.

All you need to know: September equinox

We have an equinox coming up on September 23. Happy autumn, Northern Hemisphere. Happy spring, Southern Hemisphere.

All you need to know: 2019’s Harvest Moon

It’s an early Harvest Moon in 2019, coming up on September 13 and 14 for the Northern Hemisphere.

All you need to know: Zodiacal light

The zodiacal light is an eerie light extending up from the horizon before true dawn begins. Southern Hemisphere? Look after sunset!

September guide to the bright planets

There are only 2 planets easy to see in September 2019. Jupiter and Saturn can be found in the sky at nightfall and stay out until late night. Mercury and Venus are lost in the glow of sunset. Mars hides in the glare of sunrise.

Altair: Bright star of the Eagle

Altair is only 16.8 light-years from Earth, making it one of our closest stellar neighbors. At least 2 features of the star make it distinctive. For one thing, Altair needs only 10 hours to spin once on its axis, in contrast to roughly a month for our sun.

How many supermoons in 2019?

We had 3 full supermoons (close full moons) earlier this year. Now we’re having 3 new supermoons (close new moons). The dates are August 1 and 30, plus September 28. The August 30 supermoon will be the closest of this year.

A celestial cloud of swirling gases.

See Messier 8, the Lagoon Nebula

The Lagoon – aka M8 – is the largest and brightest nebula, or cloud in space, in the vicinity of the Teapot asterism in the constellation Sagittarius.

A large, 3-lobed cloud in space.

See Messier 20, the Trifid Nebula

The Trifid is another famous binocular object, visible in the direction toward the galaxy’s center. Its name means “divided into three lobes.” If you view this nebula through a telescope, you’ll see why.

Barren, rocky landscape with snow patches. Blue sky.

Astronomy ambassadors to Chile: ALMA radio telescope

Learn what it would be like to travel to Chile – sometimes called astronomy’s world capital – in this final report from Robert Pettengill with the Astronomy in Chile Educator Ambassador Program. Thank you for your dispatches, Rob!

Andromeda galaxy, closest large spiral

The Andromeda galaxy is the closest big galaxy to our Milky Way. At 2.5 million light-years, it’s the most distant thing you can see with the eye alone. The moon is waning. It’s the right time of year. Time to start looking! 

What are the full moon names?

Lists of common full moon names – both by month and by season – for North America. Also, Blue Moons … and a word about full moon names in the Southern Hemisphere.

What is the moon illusion?

It’s nearly full moon. So you might see an extra-large-looking moon low in the sky, one evening soon. Why does the moon look so big? It’s because of the “moon illusion,” a trick your brain is playing.

Perseid meteors 2019: All you need to know

In 2019, the peak mornings for the Perseid meteor shower – around August 11, 12 and 13 – will be troubled by moonlight. Plan to watch for Perseid meteors the weekend of Friday, August 9, to Sunday, August 11.

How to watch the Perseids in moonlight

You can avoid the moon during the 2019 Perseid meteor shower by watching in the days before the peak, in the hours before dawn. Or … you can embrace the moon. Here’s how to enjoy the Perseids in moonlight.

61 Cygni is the Flying Star

Although it’s not bright, 61 Cygni moves exceptionally rapidly against the background of more distant stars. Its motion reveals its nearness to Earth.

A space-based perspective showing an earthly vantagepoint on the moon, Jupiter and Saturn in December, 2020; Jupiter and Saturn appear close together.

When Jupiter and Saturn meet

Jupiter and Saturn have appeared close on our sky’s dome throughout 2019, but they’re due to get even closer in the coming months. Their conjunction will come on December 21, 2020. Here’s how to watch them.

Albireo, beloved double star

Albireo is known best for the striking color contrast between its two stars – the brighter gold star and the dimmer blue star.

Looking along a road toward a large telescope dome, with a second dome to the right.

Astronomy ambassadors in Chile: Cerro Pachón and Cerro Tololo

Robert Pettengill reports from the busy ACEAP (Astronomy in Chile Educator Ambassador Program) annual trip, happening now in Chile.