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FAQs

Will I see the northern lights tonight?

UPDATED MAY 24, 2013 AT 1900 UTC (2 p.m. CDT). An M5-class solar flare on May 22, 2013 released a coronal mass ejection or CME. which has – as expected – now delivered a glancing blow to Earth’s magnetic field. The Advanced Composition Explorer (ACE) spacecraft – used by the Space Weather Prediction Center to provide warnings of these events – detected it beginning at about 1735 UTC (12:35 p.m. CDT) today. The Space Weather Prediction Center says to look for G1 (minor) geomagnetic storm levels over the next 24 hours. The estimate is for a 55% chance of polar geomagnetic storms in response to the strike. Aurora alert at high latitudes.

What is a supermoon?

Full moon via Lance Bullion

Full moon via Lance Bullion

What’s a supermoon? We confess: before a few years ago, we in astronomy had never heard that term. To the best of our knowledge, the term supermoon was coined by the astrologer Richard Nolle over 30 years ago. The term is only now coming into popular usage. Nolle has defined a supermoon as:

… a new or full moon which occurs with the moon at or near (within 90% of) its closest approach to Earth in a given orbit.

That’s a pretty generous definition and allows for many supermoons. The first “super” full moon – for 2013 – is tonight!

Video: How does toothpaste make orange juice taste bad?

Via Bytesize Science

Via Bytesize Science

On the latest video from ByteSize Science – released May 20, 2013 – the American Chemical Society (AMS) explains why orange juice and toothpaste is such a bad taste combo.

What are cloud streets?

cloud-streets-bering-sea-20jan2006-540

Cloud streets over the Bering Sea on January 20, 2006. Image Credit: Jesse Allen, NASA.

Cloud streets are long rows of cumulus clouds that are oriented parallel to the direction of the wind. Check out these cool images!

What are the 10 deadliest U.S. tornadoes?

 A radar image of the supercell that produced the 2011 Joplin tornado. Base reflectivity is on the left and storm relative velocity on the right. The area of high reflectivity just to the right of the Joplin label is debris lofted into the air by the tornado.

A radar image of the supercell that produced the devasting tornado in Joplin, Missouri on May 22, 2011. Base reflectivity is on the left and storm relative velocity on the right. The area of high reflectivity just to the right of the Joplin label is debris lofted into the air by the tornado. Image via Wikimedia Commons.

These are the 10 deadliest U.S. tornadoes since 1900.

What makes a halo around the sun or moon?

View larger. | Halo around the sun seen over New Jersey by EarthSky Facebook friend Jay Herbst.  Thank you, Jay!

View larger. | Halo around the sun seen over New Jersey by EarthSky Facebook friend Jay Herbst. Thank you, Jay!

A ring or circle of light around the sun or moon is called a halo by scientists. We get many messages throughout each year from people who’ve just spotted a ring around the sun or moon. On May 14, 2013 a solar halo was seen over the U.S. east coast … see photos here. People want to know: what causes a halo around the sun or moon?

Why aren’t there eclipses at every full and new moon?

Photo credit: pizzodisevo

A solar eclipse happens at the new moon – when the moon passes between the sun and Earth. A lunar eclipse happens when the Earth, sun and moon align in space, with Earth in the middle. Why aren’t there eclipses at every full and new moon?

How can I watch the May 9-10 solar eclipse safely … or online?

Big fun in Austin, Texas at the May 20, 2012 solar eclipse when an EarthSky employee passed out solar eclipse glasses at a local restaurant.

Whether you’re in a location to view the May 9-10 “ring of fire” annular eclipse, or not, this post can help you see it. If you’re not in the eclipse path, click inside for a link to online viewing. If you’re in eclipse path, you must find a way to protect your eyes. Amateur astronomer with a telescopes will be using safe solar filters on the sky end of their ‘scopes to watch the eclipse. If you don’t have this setup, you still have options. Just remember, east of the International Date Line, the ring of fire eclipse happens May 9, but if you’re in Australia, the eclipse happens after sunrise May 10. Click inside for safe eclipse viewing methods.

Why were prehistoric insects so huge?

OK .. they were never quite this big!

Do you complain about dead bugs on your windshield? Well, be thankful that insects today are considerably smaller than some of their prehistoric ancestors.

Why more Eta Aquarid meteors in Southern Hemisphere?

Image Credit: kevincole

Image Credit: kevincole

Everyone around the globe can enjoy the Eta Aquarid meteor shower in early May. But it’s better viewed from the Southern Hemisphere than the Northern Hemisphere. Why? If you traced the paths of Eta Aquarid meteors backward on the sky’s dome, you’d find that these meteors appear to stream from an asterism, or recognizable pattern of stars, known as the Water Jar in the constellation Aquarius. The later sunrises in the Southern Hemisphere at this time of year let Aquarius rise higher into the predawn sky as seen from that part of the globe. More details inside this post.