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.
Continue reading “Scientists in Japan Have Found a Detailed Record of the Earth’s Last Magnetic Reversal, 773,000 Years Ago”
Northern Canada has been keeping a secret from the rest of the world. It’s home to “Resurrection,” a tectonic plate that has been much theorized but never found until now. A team of researchers used what amounts to a CAT scan of northern Canada and the mantle underneath it to find the missing plate.
Finding it could lead to better hazard prediction and also to finding mineral and hydrocarbon deposits. But better than that, it’s helping scientists piece together Earth’s history.
Continue reading “Geologists Have Found the Earth’s Missing Tectonic Plate”
Ever since NASA’s Magellan orbiter was able to peak beneath Venus’ dense cloud layer and map out the surface, scientists have puzzled over the planet’s geological history. One of the greatest mysteries is the role volcanic activity has played in shaping Venus’ surface. In particular, there are what is known as “tesserae,” tectonically deformed regions on the surface that often stand above the surrounding landscape.
These features comprise about 7% of the planet’s surface and are consistently the oldest features in their immediate surroundings (dating to about 750 million years ago). In a new study, an international team of geologists and Earth scientists showed how a significant portion of these tesserae appear to be made up of layered rock, which is similar to features on Earth that are the result of volcanic activity.
Continue reading “Ancient Terrain on Venus Looks Like it Was Formed Through Volcanism”
Most everybody knows that the dinosaurs perished rapidly in a tumultuous extinction, caused by an asteroid strike about 66 million years ago. But it looks like another extinction prior to the appearance of the dinosaurs paved the way for their long reign. That extinction took place about 233 million years ago.
And scientists have only now discovered it.
Continue reading “A New Mass Extinction has been Discovered, Wiping Out Life 233 Million Years Ago, and Leading to the Rise of the Dinosaurs”
Scientists are getting better at understanding exoplanets. We now know that they’re plentiful, and that they can even orbit dead white dwarf stars. Researchers are also getting better at understanding how they form, and what they’re made of.
A new study says that some carbon-rich exoplanets could be made of silica, and even diamonds, under the right circumstances.
Continue reading “There Could Be Carbon-Rich Exoplanets Made Of Diamonds”
It takes oxygen to make iron rust. So when scientists discovered hematite spread widely through lunar high latitudes, they were surprised. How did that happen?
A new study suggests that oxygen from Earth could be playing a role in rusting the Moon.
Continue reading “Earth’s Oxygen Could be Making the Moon Rust”
Hundreds of millions of years ago, Earth went through two episodes of severe glaciation. These two episodes—the Sturtian and the Marinoan glaciations—occured during the Earth’s Cryogenian Period. The Cryogenian lasted from about 720 million to 635 million years ago.
The phenomenon is called “Snowball Earth” and both instances of it happened in pretty quick succession. And while a planet encased in ice and snow sounds devastating, these episodes may have paved the way for the development of complex life.
The question is, what caused the Earth to freeze over like that?
Continue reading “Did Snowball Earth Happen Because of a Sudden Drop in Sunlight?”
Could lava tubes on the Moon and Mars play a role in establishing a human presence on those worlds? Possibly, according to a team of researchers. Their new study shows that lunar and Martian lava tubes might be enormous, and easily large enough to accommodate a base.
Continue reading “Lava Tubes on the Moon and Mars are Really, Really Big. Big Enough to Fit an Entire Planetary Base”
Earth’s lithosphere is made up of seven large tectonic plates and a number of smaller ones. The theory of plate tectonics that describes how these plates move is about 50 years old. But there’s never really been an understanding of how this system developed, and how the Earth’s shell split into separate plates and started moving.
Now a group of researchers have a possible explanation.
Continue reading “What Cracked the Earth’s Outer Shell and Started its Plate Tectonics?”
Venus’ surface is no stranger to volcanoes. Radar images show more than 1,000 volcanic structures on the planet. But for the most part, they appear to be ancient and inactive.
Now a new study says that Venus is still volcanically active, and has identified 37 volcanic structures that were recently active. If true, there’s more going on inside Venus than thought.
Continue reading “It Looks Like There are Still Active Volcanoes on Venus”