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Astronomy Essentials

Photo Credit:  A. Dupree, R. Gilliland, NASA
Blogs | Feb 10, 2015

How far is Betelgeuse?

Finding star distances isn’t easy. Here’s how it’s done, and why astronomers recently modified the distance estimate to the famous star Betelgeuse.

Circumpolar stars, via Wikimedia Commons
FAQs | Feb 03, 2015

What are circumpolar stars?

From Earth’s North and South Poles, all the stars appear as circumpolar. No star rises or sets. At Earth’s equator, no star is circumpolar. And in between?

Groundhog Day
Tonight | Feb 02, 2015

Everything you need to know: Groundhog Day 2015

Groundhog Day – a celebration with its roots in astronomy – comes every year on February 2. It’s the year’s first “cross-quarter” day.

J-shaped Scorpius with Shaula and Lesath
Tonight | Feb 02, 2015

Two stars in Scorpius are a harbinger of spring

Will you see the Scorpion’s stinger stars – Shaula and Lesath – in the cold dawn sky? Look southeast anytime this month, to enjoy a Pawnee version of Groundhog Day.

Moon shot with blue filter via our friend Jv Noriega
Tonight | Jan 14, 2015

When is the next Blue Moon?

Blue Moon can be second of two full moons in a month. Or it can be third of four full moons in a season. Next Blue Moon is the second full moon of July, 2015.

Total solar eclipse via Fred Espenak
Blogs | Jan 07, 2015

How many solar and lunar eclipses in one calendar year?

Each calendar year has at least four eclipses – two solar and two lunar. Most years have four, but five, six or even seven eclipses are also possible.

Meteor via Cumbrian Sky
Blogs | Tonight | Jan 07, 2015

When is the next meteor shower?

No major meteor showers are predicted until the Lyrid shower, peaking on the morning of April 23, 2015. Between now and then … fireball season!

earth_sun_300
FAQs | Jan 03, 2015

Are the December solstice and January perihelion related?

December solstice 2014 is December 21. Earth is closest to the sun in 2015 on January 4. Coincidence?

Quadrans Muralis via Atlas Coelestis.
Tonight | Jan 02, 2015

Everything you need to know: Quadrantid meteor shower

The 2015 Quadrantid meteor shower is likely to produce the most meteors before dawn January 4, although in the glare of the almost-full moon.

quadrantid-radiant-cp
Tonight | Jan 02, 2015

Quadrantid meteors fly in moonlight in early January 2015

You might see the 2015 Quadrantid meteor shower peak in moon-free skies just before dawn on January 3 or 4.