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.
Continue reading “Even If We Cut Greenhouse Gas Emissions Tomorrow, it Would Take Decades for the Earth to Start Cooling Again”
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?
Continue reading “Betelgeuse Probably Dimmed Because of Enormous Starspots”
At first glance, Jupiter’s moon Europa doesn’t seem much like Earth. It’s a moon, not a planet, and it’s covered in ice. But it does have one important thing in common with Earth: a warm, salty ocean.
Now there’s even more evidence that Europa’s sub-surface ocean is habitable.
Continue reading “More Evidence that Europa’s Oceans Could be Habitable”
So you want to colonize Mars, huh? Well Mars is a long ways away, and in order for a colony to function that far from Earthly support, things have to be thought out very carefully. Including how many people are needed to make it work.
A new study pegs the minimum number of settlers at 110.
Continue reading “The Bare Minimum Number of Martian Settlers? 110”
The Moon is easily the most well-studied object in the Solar System, (other than Earth, of course.) But it still holds some puzzles for scientists. Why, for instance, is one side of the Moon so different from the other?
Continue reading “Do We Now Understand Why the Moon’s Near and Far Sides Look So Dramatically Different?”
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.
Continue reading “How an Advanced Civilization Could Exploit a Black Hole for Nearly Limitless Energy”
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.
Continue reading “Pluto and Other Kuiper Belt Objects Started Out With Water Oceans, and Have Been Slowly Freezing Solid for Billions of Years”
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?
Continue reading “New Simulations Show How Black Holes Grow, Through Mergers and Accretion”
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.
Continue reading “The Meteor Impact that Wiped Out the Dinosaurs Created a Vast Underground Hydrothermal System”
The Chandra X-Ray Observatory has spotted a distant black hole shooting out jets of material, at close to the speed of light. No worries, this beast is about 10,000 light years away from us. It’s more of a spectacle than a danger.
But it’s a spectacle laden with scientific insights.
Continue reading “Black Hole Seen Blasting Out Jets at Close to the Speed of Light”