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Chinese rocket breaks up in northern lights

Spirit Lake, Idaho. Photo credit: Donny Mott

Spirit Lake, Idaho. Photo credit: Donny Mott

Last night, lucky observers across western North America saw a cluster of bright lights moving across the sky – the break-up of a Chinese rocket body.

Saharan dust feeds Amazon rainforest, perfectly

Conceptual image of dust from the Saharan Desert crossing the Atlantic Ocean to the Amazon rainforest in South America. Credit: Conceptual Image Lab, NASA/Goddard Space Flight Center

Conceptual image of dust from the Saharan Desert crossing the Atlantic Ocean to the Amazon rainforest in South America. Image via Conceptual Image Lab, NASA/Goddard Space Flight Center

Dust is lifted each year from the world’s largest desert, the Sahara, which lies across the northern third of Africa. This dust can be seen in satellite images, sweeping out to sea, making a 3,000-mile journey to South America. The Amazon rainforest is a dense green mass of humid jungle that covers northeast South America. The Sahara dust, a tan cloud in the air, stretches between these continents, and ties together the desert and the jungle. Scientists have been studying this process, and, as it turns out, Saharan dust feeds the Amazon rainforest just enough to replace lost nutrients there.

Buddhist statue has a mummy inside

Buddhist statue with mummy inside

Buddhist statue with mummy inside.

Ye-ow! What a story. The image above is making the rounds on science websites this week (February 23, 2015). It shows a Buddhist statue with (surprise!) a mummified body inside. A CT scan, at right on the image above, shows the mummy. It’s a strange image, but the story around it is even stranger.

Does dark matter cause mass extinctions?

This painting by Donald E. Davis depicts an asteroid slamming into tropical, shallow seas of the sulfur-rich Yucatan Peninsula in what is today southeast Mexico. The aftermath of this immense asteroid collision, which occurred approximately 65 million years ago, is believed to have caused the extinction of the dinosaurs and many other species on Earth.

Does dark matter play a role in space impacts, such as the one that may have killed the dinosaurs approximately 66 million years ago? This painting is by space artist Don Davis via Wikimedia Commons.

Earth detectors haven’t yet detected dark matter. We know it’s there only because dark matter interacts, gravitationally, with visible matter and radiation. Modern theories suggests that dark matter makes up a substantial portion of the mass of our universe, and the inner part of our galaxy, where our solar system resides, is thought to contain dark matter. This month – in a paper published February 18, 2015 in the Monthly Notices of the Royal Astronomical Society - a New York University (NYU) professor cites dark matter as the cause for earthly catastrophes, specifically mass extinctions and geologic upheavals. The idea seems far-fetched, but has an easy-to-visualize logic behind it.

Barnard’s Loop and more in Orion

View larger. | Orion Molecular Cloud Complex -  a large group of bright nebulae, dark clouds, and young stars located in the constellation of Orion - as captured by Max Corneau in Texas.  Thank you, Max!

Orion Molecular Cloud Complex – a large group of bright nebulae, dark clouds, and young stars located in the constellation of Orion – submitted to EarthSky by Max Corneau in Texas. Thank you, Max!

When you look at the sky at this time of year, one of the most prominent constellations you see is Orion the Hunter. It’s recognizable mainly for the short, straight row of three medium-bright “Belt” stars at its mid-section. See those stars on the photo above? What you don’t see, with the eye alone, is the great complex of bright and dark nebulae – vast clouds drifting in our Milky Way – in and around Orion. That’s what Max Corneau has captured in this long-exposure photograph.

Waxing moon in Taurus, heading toward Jupiter

2015-february-24-taurus-pleiades-moon-night-sky-chart

Tonight – February 24, 2015 – the fat waxing crescent moon shines in front of the constellation Taurus the Bull. Despite the lunar glare, you should be able to make out the Bull’s brightest star, Aldebaran, and the tiny, dipper-shaped Pleiades star cluster, aka the Seven Sisters.

Can you be scared to death?

Short answer: Yes, it’s possible. Newest video by the AsapSCIENCE guys.

This date in science: Closest supernova since 1604

Supernova SN 1987A, one of the brightest stellar explosions since the invention of the telescope more than 400 years ago, is no stranger to the NASA/ESA Hubble Space Telescope. The observatory has been on the frontline of studies into this brilliant dying star since its launch in 1990, three years after the supernova exploded.  Image via spacetelescope.org

Supernova SN 1987A, one of the brightest stellar explosions since the invention of the telescope more than 400 years ago.

February 24, 1987. When Supernova 1987A first appeared in earthly skies – during the night of February 23-24, 1987 – astronomers were beside themselves with delight. It was the closest observed supernova since 1604. In this shining pinpoint in our sky, those fortunate to be in Earth’s Southern Hemisphere (in whose sky the supernova appeared) could see the death throes of a giant star. The new star remained visible to the eye for many months. It has been studied by astronomers for decades since. Follow the links inside to learn more about Supernova 1987A.

Star of the week: Procyon the Little Dog Star

Orion with his Dogs. The Dog Stars are Sirius in the constellation Canis Major, and Procyon in the constellation Canis Minor. In this photo, Orion is in the upper right. Notice that the three stars of Orion’s Belt point to the brightest star in this photo, Sirius. Procyon is the bright star on the far left of the photo. Procyon and Sirius make a large triangle with the bright star Betelgeuse in Orion. Photo by Daniel McVey in Colorado. Thank you, Daniel!

It’s hard to think of Procyon – the Little Dog Star – without also thinking of the other Dog Star, Sirius. If you’re looking at the right time of year (or right time of night), you can always find Sirius because it’s the sky’s brightest star. Procyon is always near its brighter brother on the sky’s dome. Procyon isn’t nearly as bright as Sirius. It’s the 8th brightest star in the sky, and the 6th brightest of stars that are easily visible from the most populated regions of the Northern Hemisphere. Follow the links inside to learn more about Procyon, the Little Dog Star.

When is the next leap year?

2012 was a leap year.  2015 is not.  Image via free-printable-calendar.net

2012 was a leap year. 2015 is not. Image via free-printable-calendar.net

No leap year in 2015. The next leap day will be February 29, 2016. The reason for leap years explained here.