Even If We Cut Greenhouse Gas Emissions Tomorrow, it Would Take Decades for the Earth to Start Cooling Again

Our beautiful, precious, life-supporting Earth as seen on July 6, 2015 from a distance of one million miles by a NASA scientific camera aboard the Deep Space Climate Observatory spacecraft. Credits: NASA

If—or hopefully when—we cut our Greenhouse Gas (GHG) emissions, we won’t notice much difference in the climate. The Earth’s natural systems take time to absorb carbon from the atmosphere. We may have to wait decades for the temperatures to drop.

Of course, that doesn’t mean we shouldn’t do it. It’s just that we have to temper our expectations a little.

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Betelgeuse Probably Dimmed Because of Enormous Starspots

A few months ago we all watched as Betelgeuse dimmed. Between October 2019 and 22nd of February 2020 the star’s brightness dropped by a factor of about three. It went from magnitude 0.5, and from being the tenth-brightest star in the sky, to magnitude 1.7.

Naturally, we all wondered what was happening. Would it go supernova? Even though that was extremely unlikely, how could we help but wonder?

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How an Advanced Civilization Could Exploit a Black Hole for Nearly Limitless Energy

A black hole as a source of energy?

We know black holes as powerful singularities, regions in space time where gravity is so overwhelming that nothing—not even light itself—can escape.

About 50 years ago, British physicist Roger Penrose proposed that black holes could be a source of energy. Now, researchers at the University of Glasgow in Scotland have demonstrated that it may be possible.

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Pluto and Other Kuiper Belt Objects Started Out With Water Oceans, and Have Been Slowly Freezing Solid for Billions of Years

It seems unlikely that an ocean could persist on a world that never gets closer than 30 astronomical units from the Sun. But that’s the case with Pluto. Evidence shows that it has a sub-surface ocean between 100 to 180 km thick, at the boundary between the core and the mantle. Other Kuiper Belt Objects may be similar.

But time might be running out for these buried oceans, which will one day turn to ice.

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New Simulations Show How Black Holes Grow, Through Mergers and Accretion

One of the most pressing questions in astronomy concerns black holes. We know that massive stars that explode as supernovae can leave stellar mass black holes as remnants. And astrophysicists understand that process. But what about the supermassive black holes (SMBHs) like Sagittarius A-star (Sgr A*,) at the heart of the Milky Way?

SMBHs can have a billion solar masses. How do they get so big?

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The Meteor Impact that Wiped Out the Dinosaurs Created a Vast Underground Hydrothermal System

The Chicxulub impact event was an enormous catastrophe that left a huge imprint on the Earth’s surface. Not only did it cause the mass extinction of the dinosaurs, it left a crater 180 km (112 miles) in diameter, and deposited a worldwide layer of concentrated iridium in the Earth’s crust.

But a new study shows that the impact also left its mark deep underground, in the form of a vast hydrothermal system that modified a massive chunk of the Earth’s crust.

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