1381–1400 of 2,477 results
Persistent Dust, Impermanent Nebula

Observing

Run Away With These Runaway Stars

Three stars that once belonged to Orion flew the coop millions of years ago, but you can catch up with them with binoculars the next clear night.

This Week's Sky at a Glance logo

This Week's Sky At a Glance

This Week's Sky at a Glance, December 11 – 19

Sirius is the brightest star in the night sky. Have you ever tried to catch Sirius rising? It rises between 7:30 and 8:30 p.m., depending on where you live.

Capella x 2

Observing

Tale of Capella and the Two Red Dwarfs

Bright Capella plays it close to the vest when it comes to companions, but with a good map and steady skies you can track down its dwarf binary.

Meteor

Observing

Geminids in 2015: Moonless and Marvelous

The nights of December 13th and 14th offer dark nights for this popular under-appreciated meteor display.

Measuring skyglow in Arizona

Save Dark Skies

Rate the Darkness of Your Sky

A new website shows how light pollution spreads around the globe — using data gathered by its users.

This Week's Sky At a Glance

This Week's Sky at a Glance, December 4 – 12

The Summer Triangle remains in the western sky these cold evenings. Its brightest star is Vega; look above for Deneb and farther to Vega's left is Altair.

Comet Catalina on Dec. 2, 2015

Observing

Get a Predawn Peek of Comet Catalina

Our current visitor from the Oort Cloud, rising into northern skies at last, can be glimpsed with binoculars low in the east before dawn. Spotting it will be especially easy on December 7th.

Venus by the Slice

Observing

Moon Occults Venus on December 7th

After taking us to Comet Catalina's doorstep, the Moon covers Venus in a spectacular daytime occultation visible from most of North and Central America on Monday, December 7, 2015.

Predawn planets on Dec 6-7_f

Sky Tour Astronomy Podcast

Tour December's Sky: Planets and Meteors

This month offers great variety in the night sky: planets (and a comet!) before dawn, a strong meteor shower, and a parade of bright stars after sunset.

This Week's Sky At a Glance

This Week's Sky at a Glance, November 27 — December 5

Before and during dawn, Venus shines within 5° of Spica from Saturday through December 2nd. Look also for star Gamma Virginis just to Mars's left.

Observing

Moon Illusion is All in Your Head

Is perception reality? Not when it comes to the Moon illusion. See the truth with your own eyes at the rising of the next full Moon.

This Week's Sky At a Glance

This Week's Sky at a Glance, November 20 – 28

Before dawn Saturday morning, look east for Jupiter and Venus. Between them is little orange Mars. Look carefully: very close to Mars is the star Eta Virginis.

Comin' at ya' Baby

Observing

Watch a Black Hole Eat Dinner

S5 0716+71, a bright blazar currently in a feeding frenzy, invites you over for dinner the next clear night.

Leonid fireball from 2001

Observing

Leonid Meteors in 2015: Modest but Moonless

This year's Leonid meteor shower, which peaks tonight, will offer modest numbers of "shooting stars" — but might reward you with some dazzling fireballs.

This Week's Sky at a Glance logo

This Week's Sky At a Glance

This Week's Sky at a Glance, November 13 – 21

The waxing crescent Moon hangs in the southwest after sunset. As twilight fades, can you make out any last stars of summery Sagittarius to its left? Bring binoculars!

Blue Q-tip

Observing

Catalina Comet Sails Into Northern Skies

Comet Catalina returns this month with naked-eye potential. Follow its every move with our guide and maps.

This Week's Sky At a Glance

This Week's Sky at a Glance, November 6 – 14

As predicted, this has become a great year for the Taurid meteor shower. Occasional brilliant meteors should continue through about Tuesday, November 11th.

Far but Familiar

Observing

Triple Treasure in Triangulum's Pinwheel

Travel 2.7 million light-years from home to the Pinwheel Galaxy, where we'll visit a supergiant star, an extragalactic globular cluster, and one of the largest nebulae in the known universe.

Taurid 2005 by Hiroyuki Iida

Observing

Be Alert for Taurid Fireballs This Week

If you see a really bright autumn fireball, it might be a Taurid meteor — a fragment of Comet 2P/Encke.

This Week's Sky at a Glance logo

This Week's Sky At a Glance

This Week's Sky at a Glance, October 30 – November 7

The long-lasting Taurid meteor shower is sparse, but a high proportion of its meteors are bright. This year we're predicted to see more of them than usual.