Californians woke up to an alien-looking sky this morning, Wednesday, September 9, 2020.Continue reading “Can you tell the difference between California, Venus, Titan and Mars? Hint: California is the one with buildings.”
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?”
At the bottom of the ocean in the South Pacific Gyre, there’s a sediment layer that is among the most nutrient-starved environments on Earth. Because of conditions in that area, there’s almost no “marine snow”—the shower of organic debris common in the ocean—that falls to the ocean floor. Without all that organic debris falling to the floor, there’s a severe lack of nutrients there, and that makes this one of the least hospitable places on Earth.
A team of researchers took sediment samples from that area, and extracted 101.5 million year old microbes. When they “fed” those microbes, they sprang back to life.
The results are expanding our knowledge of microbial life and how long it can be dormant when conditions force it to be.Continue reading “Microbes Were Dormant for Over 100 Million Years, But They Were Able to Spring Back to Life”
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?”
Natural processes here on Earth continually re-shape the planet’s surface. Craters from ancient asteroid strikes are erased in a short period of time, in geological terms. So how can researchers understand Earth’s history, and how thoroughly it may have been pummeled by asteroid strikes?
Scientists can turn their attention to our ancient companion, the Moon.Continue reading “800 Million Years Ago, it Was Raining Asteroids on the Earth and Moon”
The origin of Earth’s water is a big piece of the puzzle in Earth’s history. Did it come from comets and asteroids? From water-bearing space dust? The scientific debate is not settled.
Now a new study shows that water could have been delivered to Earth by organic matter.Continue reading “Organic Matter Could Have Delivered Earth’s Water”
An iceberg that calved off of from a larger ice formation has spent three years floating on the ocean near Antarctica. The iceberg broke off of the Larsen Ice Shelf in mid-July 2017. It’s been battered and split up into three pieces, but it’s still going.Continue reading “This Giant Iceberg Has Been Sailing the Southern Seas for Three Years Now”
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 new study shows that the Moon is more metal-rich than previously thought. That has some far-reaching implications for our understanding of the Moon’s formation. If their results are solid, it means that we may need to re-think the giant impact hypothesis for the formation of the Moon.Continue reading “The Moon Might Be More Metal-Rich Than We Thought”
On July 2, 2019, the Moon cast its shadow on the surface of the Earth. This time, the shadow’s path travelled across the South Pacific Ocean. It also passed over some of Argentina and Chile. For surface dwellers in the path, the Moon briefly blocked the Sun, turning night into day.
But for one “eye” in orbit around the Moon, the view was different. A camera on a tiny satellite watched as the circular shadow of the Moon moved over the Earth’s surface.Continue reading “Last Year’s Total Solar Eclipse on Earth, Seen From the Moon”