Posts by 

Kelly Kizer Whitt

Here’s what ‘habitable’ means to astronomers

When astronomers say a distant world is 'habitable,' what do they mean? Do they mean humans could live there? Do they mean we've discovered alien life?

Crew-11 astronauts returned to Earth this morning

The 4 Crew-11 astronauts returned to Earth earlier this morning, January 15. The astronaut who needed evacuation, NASA says, is "doing fine".

Meet the Winter Circle, aka the Winter Hexagon

The brightest stars in the Northern Hemisphere's winter sky form the shape of the Winter Circle, or Hexagon, that will help you locate 6 constellations.

Earth’s ice ages shaped by tiny tugs from Mars

Computer simulations show the presence of Mars affects the cycles that cause Earth's ice ages. Without Mars, those cycles vanish.

Top 10 brightest objects in our solar system

Ready for some easy astronomy? How about the top 10 brightest objects in our solar system? If you've seen every one of these objects, congrats!

Potentially hazardous asteroid to pass Earth safely Monday

A potentially hazardous asteroid, 2005 UK1, will safely pass Earth on January 12, 2026. At this time it will be more than 32 times the moon's distance away.

Pictor and Reticulum, the Painter’s Easel and Net

Pictor and Reticulum, the Painter's Easel and Net, are two constellations in southern skies on either side of the Large Magellanic Cloud.

Greatest elongation, superior and inferior conjunction

When Mercury and Venus are as far from the sun as they get from our earthly point of view, they are at greatest elongation. It is the best time to observe them.

Deep-sky objects: Small telescope and binocular targets

Deep-sky objects - including bright and dark nebulae, star clusters and distant galaxies - are favorite targets for amateur stargazers.

Sky measurements: Degrees, arcminutes and arcseconds

What are sky measurements - or distances - in the night sky? Here's what it means for objects to be several degrees (or arcminutes or arcseconds) apart.

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