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See 5 bright planets at once

Since late January, and through mid-February, 5 bright planets are visible at once in the predawn sky. This image is from February 8, 2016.  It's by Eliot Herman in Tucson, Arizona.  View on Flickr.

Since late January, and through mid-February, 5 bright planets are visible at once in the predawn sky. This image is from February 8, 2016. It’s by Eliot Herman in Tucson, Arizona.

UPDATE February 8, 2016. The new moon comes to pass on February 8, 2016, at which juncture the moon transitions from the morning to evening sky. Many people around the world witnessed the moon sweeping by all five visible (naked-eye) planets from late January until February 7, 2016. But you still can see all these planets together in the morning sky for at least another week. Read more inside…

How do snowflakes get their shape?

Photo by EarthSky Facebook friend Paula Lancaster Lupi of a snowflake and frost on her car window.

Anyone still interested in snow?

What’s a safe distance between us and an exploding star?

Artist's illusration of a supernova via SmithsonianScience.org

Artist’s illustration of a supernova via SmithsonianScience.org

A supernova is a star explosion – destructive on a scale almost beyond human imagining. If our sun exploded as a supernova, the resulting shock wave probably wouldn’t destroy the whole Earth, but the side of Earth facing the sun would boil away. Clearly, the sun’s distance – 8 light-minutes away – isn’t safe. Fortunately, our sun isn’t the sort of star destined to explode as a supernova. But other stars, beyond our solar system, will. What is the closest safe distance? Follow the links inside to learn more.

When does the Age of Aquarius begin?

Leonardo da Vinci's famous Vitruvian Man, a drawing created circa 1487, with the 7 chakras or energy centers indicated.  Image via Wikimedia Commons

Leonardo da Vinci’s famous Vitruvian Man, a drawing created circa 1487, with the 7 chakras or energy centers indicated. Image via Wikimedia Commons

The Age of Aquarius is an astrological age, which shifts roughly every 2,150 years. It’s defined by the sun’s position at the time of the March, or vernal, equinox. The Age of Aquarius begins when the March equinox point moves out of the constellation Pisces and into the constellation Aquarius. But there’s no definitive answer as to when that will be. This post explores some of the possibilities.

Dates of sun’s entry into each constellation of the Zodiac

506px-Capricornus_IAU.svg

The sun enters the constellation Capricornus the Sea-goat on January 20, 2016. Dates of sun’s entry into each zodiacal constellation and the corresponding ecliptic longitude (sun’s position in degrees, east of the March equinox point), inside.

What are cloud streets?

NASA's Aqua satellite captured this image of cloud streets over the Black Sea on January 8, 2015.  NASA Earth Observatory image courtesy Jeff Schmaltz LANCE/EOSDIS MODIS Rapid Response Team, GSFC.

NASA’s Aqua satellite captured this image of cloud streets over the Black Sea on January 8, 2015. NASA Earth Observatory image courtesy Jeff Schmaltz LANCE/EOSDIS MODIS Rapid Response Team, GSFC.

Cloud streets are long rows of cumulus clouds that are oriented parallel to the direction of the wind. They’re formed by convection rolls of rising warm air and sinking cool air, and ultimately become oriented parallel to the direction of the wind. Check out some cool images of cloud streets, inside.

What is Lunar X?

Aniruddha Bhat in Maryland caught this Lunar X on January 16, 2016.

Aniruddha Bhat in Maryland caught this Lunar X last night (January 16, 2016).

Lunar X is a famous optical feature on the moon, visible through telescopes. When the terminator – or line between light and dark on the moon – is located in just the right place, it appears as the letter X on the moon’s surface. A sign of an alien visitation? No.

Why stars seem brighter this time of year

On June, July and August evenings, we look toward the galaxy’s center as indicated by the red arrows. On December, January and February evenings, we look away from the center, as indicated by the blue arrows. Other features, including our galaxy’s primary spiral arms and the sun’s location in the Orion Spur, are also shown. Artist’s illustration via NASA/JPL/Caltech/R.Hurt. View larger.

As seen from the Northern Hemisphere, the stars seem brighter in winter. Here’s why …

What causes the aurora borealis or northern lights?

Photo by Ruslan Merzlyakov. Visit him on Facebook.

Photo by Ruslan Merzlyakov.

People at high northern latitudes sometimes experience an ethereal display of colored lights shimmering across the night sky – the aurora borealis or northern lights. What causes them?
Don’t miss the photos at the bottom of this post!

Supermoons of 2016

What most call a Blue Moon isn't blue in color. It's only Blue in name. This great moon photo from EarthSky Facebook friend Rebecca Lacey in Cambridge, Idaho.

Moon photo is from Rebecca Lacey in Cambridge, Idaho.

According to the definition of supermoon coined by Nolle, the year 2016 has a total of six supermoons. The new moons of March, April and May and the full moons of October, November and December all qualify as supermoons. Follow the links inside to learn about the supermoons of 2016.