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Star of the week: Hadar

Hadar, aka Beta Centauri, joins Alpha Centauri in pointing to the Southern Cross. It’s a triple system. Two of its stars will someday become nearby supernovae.

See it! Meteors, moon, Venus photos

The Lyrid meteor shower didn’t produced as many meteors as hoped, but we some lovely photos. And the moon and Venus were awesome Sunday morning!

Asteroid 2014 JO25 bigger than expected

It’s coming closer today than any asteroid this large since 2004. It came into view of small telescopes a few hours ago. Early radar observations indicate it’s bigger than we thought.

All you need to know: Lyrid meteors

April 22 is the likely peak morning. Try April 21 and 23 as well. For this year’s Lyrid meteor shower, the moon is out of the way!

Why does the moon seem to follow me?

Here’s something you – or your kids – might notice. When you’re moving in a car, earthly objects get left behind, but the moon seems to follow. Why?

Watch for Venus before dawn

While watching Jupiter and the moon around April 9-11, don’t forget Venus! It passed between us and the sun on March 25 and now blazes in the east before dawn.

Jupiter and its moons

The 4 largest moons of Jupiter – called the Galilean satellites – are Io, Europa, Ganymede and Callisto. Recent photos here.

Overtaking the king of planets

This is what the opposition of Jupiter means.

April guide to the bright planets

All 5 bright planets appear in the April night sky.

What is Lunar X?

Is Lunar X a sign of an alien visitation? No. It’s an example of how lighting and topography can combine to produce a pattern that seems familiar to the human eye.

No kidding! April Fools’ Comet

Comet 41P/Tuttle-Giacombini-Kres├ík will be closer to Earth on April 1 than it’s been since its discovery. You need a telescope to see it, but there’s an online viewing Friday night.

What is earthshine?

When you see the crescent moon after sunset this week, notice the pale glow on its unlit portion. This glow is called earthshine.

Colors of scintillating Venus

Venus reaches inferior conjunction today, officially leaving the evening sky. It has been low in the sky, where Earth’s atmosphere has caused Venus to scintillate, or twinkle, in many colors.

Venus after sunset and before sunrise!

The planet Venus is now appearing in the west after sunset and in the east before sunrise. Don’t believe it? Astronomer Bruce McClure reports on his observation.

What is stellar magnitude?

Brightest stars to the eye are 1st magnitude, and dimmest stars to the naked eye are 6th magnitude. How the magnitude scale works in astronomy and why it’s useful.

Watch the sun’s shift on your horizon

Here’s a fun activity for the coming months. Note how far the sun moves on your horizon each day, as spring shifts toward summer (or autumn towards winter).

March equinox! Happy spring or fall

The 2017 vernal or spring (or fall) equinox occurred on March 20 at 10:29 UTC. Spring for the north – fall for the south – of Earth’s globe.

Fastest sunsets near equinoxes

We’re talking about the amount of time needed for the body of the sun to sink below the horizon. It’s true. The sun actually sets faster around the time of an equinox.

How to take great photos of star trails

When a camera captures a star’s movement across the sky, it’s called a star trail. An astrophotographer explains how he does it.

Total eclipse of sun: August 21, 2017

All you need to know about the 1st total solar eclipse visible from the contiguous U.S. since 1979, from eclipse master Fred Espenak.