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Powerful 7.9-magnitude earthquake rocks Nepal

earthquake-Kharahara-tower-collapse-BBC

The U.S. Geological Survey (USGS) reports a 7.9-magnitude earthquake in Nepal today (April 25, 2015). It originally reported the quake at a 7.5-magnitude and later upgraded it. This powerful quake’s tremors were felt across the region, and into neighboring India, Pakistan and Bangladesh. Some 700 people are known to have died from the quake so far, which wrecked many historic buildings.

First quarter moon with Jupiter on April 25

The moon's change of position relative to the planet Jupiter and the star Regulus at nightfall April 25, 26 and 27. The green line represents the ecliptic.

The moon’s change of position relative to the planet Jupiter and the star Regulus at nightfall April 25, 26 and 27. The green line represents the ecliptic.

Be sure to watch the magnificent pairing of the moon and Jupiter as darkness falls on these next few evenings – April 25, 26 and 27. The moon and Jupiter rank as the brightest and third-brightest heavenly bodies of nighttime. What’s the second-brightest? It’s blazing planet Venus, also beaming in your western sky at dusk on these April 2015 evenings.

Biggest five – or six? – mass extinctions ever

Over 99% of all the animal species that have ever lived are now extinct. Here are Earth’s biggest extinctions, in under 5 minutes. New video from AsapSCIENCE.

Love is in the air

Purple Finches at a bird feeder in Weatherly, Pennsylvania, April 22, 2015.  Photo by Tom Wildoner.

Photo taken April 22, 2015 by Tom Wildoner. Visit him on Facebook.

It’s spring here in the N. Hemisphere and the thoughts of this male Purple Finch are turning to … well, hello, ladies!

Moon near Gemini stars on April 24

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Tonight – April 24, 2015 – the rather wide waxing crescent moon passes in front of the constellation Gemini the Twins. The two brightest stars in Gemini are Castor and Pollux. The other bright star on the other side of the moon is Procyon, the brightest in Canis Minor the Lesser Dog. The king planet Jupiter, which outshines all these bright stars, lies to the east of tonight’s moon. Look for the moon to be closer to Jupiter tomorrow night, April 25.

Spectacular Calbuco volcano in Chile!

Calbuco volcano on April 22, 2015 via Flickr user Philip Oyarzo Calisto.

Calbuco volcano on April 22, 2015 via Flickr user Philip Oyarzo Calisto.

After remaining dormant for 42 years, the Calbuco volcano in southern Chile erupted twice on Wednesday (April 22, 2015). An ash cloud rose at least 15 kilometers (9 miles) above the volcano. Some 1,500 to 2,000 people were evacuated; no casualties have been reported so far. The first eruption sent up vast plumes of smoke. The second eruption later that night sent up red-hot rocks and produced volcanic lightning. Airlines cancelled flights. A flow of lava was reported into Chapo Lake, which lies lies immediately southeast of the volcano, on the same day.

More earthquakes due to human activities, says USGS

Blue dots 1960-2012.  Green dots 2013.  Red dots 2014. Note that an older methodology was used to count earthquakes from 1960-2012.  Map via USGS.

Blue dots 1960-2012. Green dots 2013. Red dots 2014. Note that an older methodology was used to count earthquakes from 1960-2012. Map via USGS.

The U.S. Geological Survey (USGS) released a new report and its first map today showing the frequency of earthquakes thought to be triggered by human practices. The agency said in its April 23, 2015 announcement:

Earthquake activity has sharply increased since 2009 in the central and eastern United States. The increase has been linked to industrial operations that dispose of wastewater by injecting it into deep wells.

Fly through Hubble’s 25th anniversary image

This visualization from NASA provides a three-dimensional perspective on Hubble’s 25th anniversary image of the nebula Gum 29 with the star cluster Westerlund 2 at its core. Wow!

Watch the Arctic ice pack vanish

Decades ago, most of Arctic’s winter ice pack was made up of thick, perennial ice. Not anymore. Watch the change in this one-minute animation.

10 things to know about brown recluse spiders

Brown recluse spider. The photo shows its size in relation to a quarter. – Photo courtesy of K-State Research and Extension

Brown recluse spider. The photo shows its size in relation to a quarter. – Photo courtesy of K-State Research and Extension

It’s their active season. Here are ten things to know about these venomous spiders that like to live where we do.