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Video: What would happen if humans suddenly disappeared?

What would happen to our planet if all us humans – for some reason – suddenly vanished? Here’s AsapSCIENCE’s take on it.

Orion Nebula is a place where new stars are born

The three stars in a short, straight row represent Orion’s Belt. A curved line of stars hangs from the Belt that represents Orion’s Sword. The Orion Nebula can be seen as a fuzzy object, about midway down in the Sword. Click here to expand image

Many people are familiar with Orion, the most noticeable of all constellations. The three stars of Orion’s Belt jump out at you midway between Orion’s two brightest stars, Betelgeuse and Rigel, which are two of the brightest stars in the sky. Once you find the Belt stars, you can also locate the Orion Nebula, otherwise known as M42, a stellar nursery where new stars are being born. If you look closely, you’ll notice a curved line of stars “hanging” from the three Belt stars. These stars represent Orion’s Sword. Look for the Orion Nebula about midway down in the Sword of Orion.

This date in science: First modern suspension bridge completed

The Menai Bridge between Wales and Anglesey is considered the first modern suspension bridge in the world. Image credit: Ingy the Wingy/Flickr

January 30, 1826. Workers completed construction of the first modern suspension bridge on this date. It was the Menai Bridge between Wales on the island of Great Britain and the smaller island of Anglesey, to the west. According to local reports about the bridge from nearly 200 years ago, travel in the strait between Wales and Anglesey was hazardous, due to shifting currents and unpredictable weather patterns. But the island of Anglesey had the Atlantic Ocean and Irish Sea to its west, and, especially after Ireland joined the United Kingdom in 1800, people increasingly wanted to use Anglesey as a jumping off point to reach the Emerald Isle by ferry boat.

Ancient skull offers clues to humans’ migration out of Africa

Views of the human skull, with missing jaw, found in western Galilee, northern Isreal and estimated at 55,000 years old. Photograph: Tel Aviv University and University of Vienna

Views of a human skull, with a missing jaw, found in northern Isreal and estimated at 55,000 years old. Photograph via Tel Aviv University and University of Vienna

An international team of researchers says a partial skull from a cave in northern Israel is some 55,000 years old. They say it sheds light on the interbreeding of our ancestors with Neanderthals and provides new insights into the migration of modern humans out of Africa.

What causes the aurora borealis or northern lights?

Reisafjorden, Norway bathing in auroras on January 2, 2014.  Copyright 2014 Tor-Ivar Næss.

Reisafjorden, Norway bathing in auroras on. When charged particles from the sun strike atoms in Earth’s atmosphere, they cause electrons in the atoms to move to a higher-energy state. When the electrons drop back to a lower energy state, they release a photon: light. This process creates the beautiful aurora, or northern lights. Image copyright 2014 Tor-Ivar Næss. Via WaitForIt on Facebook.

Don’t miss the photos at the bottom of this post!

Moon, Mars and Venus from a sea cave

View larger. | The moon, Mars and Venus from a sea cave by Jack Fusco.  Visit Jack Fusco on Facebook

Photo by Jack Fusco.

Jack Fusco captured this photo at Solana Beach in San Diego County, California on January 23. He’s working on a series of images from sea caves throughout the San Diego area.

Identify the Winter Circle and winter’s brightest stars

2015-jan-30-orion's-belt-winter-circle-winter-triangle-moon-night-sky-chart

Tonight’s chart covers a wider area of sky than we typically show. It’s in answer to a reader in Nashville, who wrote, I’ve heard mention of the Winter Circle of Stars. Could you list the stars in this circle?

Winter Circle: Winter’s brightest stars

You will find these stars at this time of year by looking southeast at early-to-mid evening, and more southward from mid-to-late evening. Although the almost-full waxing gibbous moon shines within the Winter Circle tonight, all the stars of the Winter Circle (sometimes called the Winter Hexagon) are first-magnitude stars, so they should be able to withstand tonight’s drenching moonlight. Note also that the Winter Triangle – formed by bright stars Sirius, Betelgeuse and Procyon – make up the southeast part of the Winter Circle.

Astronomers discover oldest known Earth-sized planets yet

Kepler-444 hosts five Earth-sized planets in very compact orbits. The planets were detected from the dimming that occurs when they transit the disc of their parent star, as shown in this artist's conception. Image credit: Tiago Campante/Peter Devine

Kepler-444 hosts five Earth-sized planets in very compact orbits. The planets were detected from the dimming that occurs when they transit the disc of their parent star, as shown in this artist’s conception. Image credit: Tiago Campante/Peter Devine

Scientists have located an ancient solar system, dating back to the dawn of the galaxy, which appears to be a miniature version of the inner planets in our own solar system.

Hear the birth of an iceberg

Distinctive underwater sounds announce the birth of an iceberg, say researchers. In a recent study, scientists used underwater microphones aboard buoys to record a variety of iceberg births at the Hans Glacier in Svalbard, Norway during three days in August 2013. These recordings were combined with time-lapse photos of the glacier during the same time period.

Flowing water on Vesta?

This image shows Cornelia Crater on the large asteroid Vesta. On the right is an inset image showing an example of curved gullies, indicated by the short white arrows, and a fan-shaped deposit, indicated by long white arrows. Image Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.  View larger and read more about this photo.

This image from the Dawn spacecraft shows Cornelia, a crater on the large asteroid Vesta. The inset on the right shows an example of curved gullies, indicated by the short white arrows, and a fan-shaped deposit, indicated by long white arrows. Image via NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.

Fascinating news this month about asteroid 4 Vesta – fourth asteroid to be discovered and second-most-massive asteroid after the dwarf planet 1 Ceres. NASA’s Dawn spacecraft visited Vesta from 2011 to 2013, and the new study is based on evidence from Dawn. The new study shows that – although Vesta was once assumed to be completely dry, incapable of retaining water because of the low temperatures and pressures at its surface – there’s evidence that Vesta may have had short-lived flows of water-mobilized material on its surface. Wow, yes?