EarthSky

Learning to live on the moon … underwater

Astronaut teams practice living and working on the moon in the pool at at NASA’s Neutral Buoyancy Lab.

Diagram of w-shaped constellation

Close-up on Cassiopeia the Queen

The constellation Cassiopeia the Queen has the distinct shape of a W or M. Find her in the north-northeast sky on September and October evenings.

Shiny blue balls in a white circular net.

Milky Way’s black hole appears to be getting hungrier

“We have never seen anything like this in the 24 years we have studied the supermassive black hole. It’s usually a pretty quiet, wimpy black hole on a diet. We don’t know what is driving this big feast.”

Shedding light on black holes

How much of what think you know about black holes is true, and how much is myth? To separate fact from fiction, check out this 4-minute vIdeo from NASA.

Golden ball of Saturn, surrounded by nearly edgewise rings, and a little dot of a moon.

40 years ago today: Pioneer 11 swept past Saturn

Pioneer 11 was the first spacecraft ever to encounter Saturn. A true pioneer, it paved the way for 2 more sophisticated missions – the 2 Voyagers in 1980 and ’81 – and Cassini from 2004 to 2017.

September’s birthstone is the sapphire

Sapphires are typically blue stones, with the color caused by small amounts of titanium and iron in the crystal structure. But if the crystal contains different impurities, you might also see sapphires in gray, yellow, pale pink, orange, green, violet or brown.

Orion and Sirius the Dog Star

A sign of the changing season, Sirius – the sky’s brightest star – is visible before sunup. You’ll know it’s Sirius if the very noticeable 3 stars in Orion’s Belt point to it.

Would you have believed the Great Moon Hoax?

It sounds preposterous today. But – beginning on today’s date in 1835 – a newspaper claimed a famous astronomer had found life on the moon, including bat-men and unicorns. The Great Moon Hoax was widely read and believed.

How did Pluto become a dwarf planet?

It’s been 13 years since astronomers announced Pluto would no longer be considered a major planet in our solar system. When it happened, in 2006, the decision caused a shock wave around the world.

Andromeda galaxy.

Great Square points to Andromeda galaxy

If your sky is dark, you’ll enjoy locating these stars and using this method of finding the Andromeda galaxy.