Antarctica Lost an Ice Shelf, but Gained an Island

The eastern coast of Antarctica has lost most of the Glenzer and Conger ice shelves, as seen in these satellite images taken between November 15, 1989 - January 9, 2022. Credit: NASA GSFC/UMBC JCET.

Collapsing ice shelves on the eastern coast of Antarctica has revealed something never seen before: a landform that might be an island. But this is not the first newly revealed island off the Antarctic coast. A series of islands have appeared as the ice shelves along the continent’s coastline has disintegrated over the past few years.

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Because of Extreme Drought, Lake Powell is Barely a Lake Anymore

This Copernicus Sentinel-2 image allows us a wider view of Lake Powell and its dwindling water levels amidst the climate crisis. Contains modified Copernicus Sentinel data (2022), processed by ESA.

The two largest reservoirs in the United States are now at their lowest levels since they were first created. After several decades of drought – with the past two years classified as intense drought in the US Southwest — both Lake Powell and Lake Mead are shrinking. Recent satellite images show just how dramatic the changes have been, due to the ongoing the climate crisis..

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Scientists Simulate the Climate of Arrakis. It Turns Out Dune is a Pretty Realistic Exoplanet

Is the planet Arrakis realistic? Image Credit: By The Central Intelligence Agency - The World Factbook - Algeria, Public Domain, https://commons.wikimedia.org/w/index.php?curid=29196928

Science fiction author Frank Herbert is renowned for the richly-detailed worlds he created. None of his work is more well-known than “Dune,” which took him six years to complete. Like his other work, Dune is full of detail, including the description of planet Dune, or as the Fremen call it, Arrakis.

Dune is an unforgiving desert world that suffers powerful dust storms and has no rainfall. Scientists who specialize in modelling climates set out to see how realistic Dune is compared to exoplanets. Their conclusion?

Frank Herbert did a great job, considering he created Dune in the 1960s.

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Mars Might Have Lost its Water Quickly

This artist's concept depicts the early Martian environment (right) – believed to contain liquid water and a thicker atmosphere – versus the cold, dry environment seen at Mars today (left). Image Credit: NASA's Goddard Space Flight Center

Mars is an arid place, and aside from a tiny amount of water vapour in the atmosphere, all water exists as ice. But it wasn’t always this arid. Evidence of the planet’s past wet chapter dots the surface. Paleolakes like Jezero Crater, soon to be explored by NASA’s Perseverance Rover, provide stark evidence of Mars’ ancient past. But what happened to all that water?

It disappeared into space, of course. But when? And how quickly?

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Scientists in Japan Have Found a Detailed Record of the Earth’s Last Magnetic Reversal, 773,000 Years Ago

Earth Observation has come a long way. But if satellites could orbit closer to Earth, in VLEO, then our observations would be a lot better. Image Credit: NASA Earth Observatory.

Every 200,000 to 300,000 years Earth’s magnetic poles reverse. What was once the north pole becomes the south, and vice versa. It’s a time of invisible upheaval.

The last reversal was unusual because it was so long ago. For some reason, the poles have remained oriented the way they are now for about three-quarters of a million years. A new study has revealed some of the detail of that reversal.

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Pluto has Snowcapped Mountains, But Why?

On the left, the region of "Cthulhu" near the equator of Pluto and on the right, the Alps on Earth. Two identical landscapes, created by very different processes. Image Credit: © NASA / Johns Hopkins University Applied Physics Laboratory / Southwest Research Institute © Thomas Pesquet / ESA

We can thank NASA’s New Horizons spacecraft for opening our eyes up to Pluto’s complexity. On July 14th, 2015, the spacecraft came within 12,500 km (7,800 mi) of the dwarf planet. During the flyby, New Horizons was able to characterize Pluto’s atmosphere and its surface.

Among the things New Horizons saw was a region of snowcapped mountains.

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Ancient Meteorites Can be Found Embedded in Rocks, Like Fossils

Fossil meteorites from the mid-Ordovician period, around 460 million years ago, indicate that Earth may have been hit by debris from an asteroid collision at that time. Image credit - Birger Schmitz

Comets visit the inner Solar System, and leave without saying goodbye. Maybe they leave a trail of dust behind, and when the Earth passes through it, we get a pretty light show in the night sky, in the form of a meteor shower. Likewise, asteroids frequently go whizzing by, though they don’t leave us with a pyrotechnic display.

Sometimes these rocky interlopers head straight for Earth. And when they do, the results can be cataclysmic, like when an asteroid struck Earth about 66 million years ago, wiping out the dinosaurs and 75% of life on Earth. Other times, it’s not quite as cataclysmic, but still devastating, like in about 2350 BC, when debris from a disintegrating comet may have caused the collapse of an ancient empire.

But regardless of the severity of any of these individual events, the conclusion is crystal clear: Earth’s history is intertwined with the coming and going of space rocks. The evidence is all around us, sort of.

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There’s A Fire in Greenland… Again. It’s 10 Degrees Hotter Than Normal

This fire in Greenland is near Sisimiut, in Western Greenland. It was likely caused by a hiker. Image Credit: NASA Earth Observatory

As global warming ramps up, expect to see Greenland in the news a lot. That’s because its ice sheet is under threat of melting. But that’s not the only reason. The other reason is fire.

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NASA’s Long-Term Climate Predictions have Proven to be Very Accurate, Within 1/20th of a Degree Celsius

The map shows temperature changes for the last decade—January 2000 to December 2009—relative to the 1951-1980 mean. Credit: NASA

There are a handful of major science institutions around the world that keep track of the Earth’s temperature. They all clearly show that the world’s temperature has risen in the past few decades. One of those institutions is NASA.

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Astronomy Cast Ep. 516: Polar Vortices

It’s cold right now. Okay, fine, here on Vancouver Island, it’s actually pretty warm. But for the rest of Canada and big parts of the US, it’s terrifyingly cold. Colder than Mars or the North Pole cold. This is all thanks to the break up of the polar vortex. What are polar vertices, how do they form, and where else to we find them in the Solar System?

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