Last Year’s Total Solar Eclipse on Earth, Seen From the Moon

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.

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It Should Be Easiest to Search for Young Earth-like Planets When They’re Completely Covered in Magma

How did Earth evolve from an ocean of magma to the vibrant, life-supporting, blue jewel it is now? In its early years, the Earth was a blistering hot ball of magma. Now, 4.5 billion years later, it’s barely recognizable.

Is it possible to find exoplanets out there in the vast expanse, which are young molten globes much like young Earth was? How many of them can we expect to find? Where will we find them?

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Astronomers Have Found the Star/Exoplanet Combo That’s the Best Twin to the Sun/Earth

At times, it seems like there’s an indundation of announcements featuring discoveries of “Earth-like” planets. And while those announcements are exciting, and scientifically noteworthy, there’s always a little question picking away at them: exactly how Earth-like are they, really?

After all, Earth is defined by its relationship with the Sun.

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Ocean Circulation Might Be the Key to Finding Habitable Exoplanets

Artist's depiction of a waterworld. A new study suggests that Earth is in a minority when it comes to planets, and that most habitable planets may be greater than 90% ocean. Credit: David A. Aguilar (CfA)

We’ve found thousands and thousands of exoplanets now. And spacecraft like TESS will likely find thousands and thousands more of them. But most exoplanets are gassy giants, molten hell-holes, or frozen wastes. How can we find those needles-in-the-haystack habitable worlds that may be out there? How can we narrow our search?

Well, first of all, we need to find water. Oceans, preferably, since that’s where life began on Earth. And according to a new study, those oceans need to circulate in particular ways to support life.

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Magnetic north is migrating towards Siberia. Here’s why

The North Pole ain’t what it used to be. Well, the geographic North Pole stays fixed over time (mostly because we define it to stay fixed over time) but the magnetic north pole constantly moves. And over the past decade it’s been moving out of Canada towards Siberia four times faster than it has in the past couple centuries. Armed with data from the ESA’s Swarm satellite, scientists might finally know why: the shifting of our magnetic field north pole is caused by a titanic struggle between two competing massive magnetic plumes.

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Worlds With Hydrogen in Their Atmospheres Could Be the Perfect Place to Search for Life

We’re waiting patiently for telescopes like the James Webb Space Telescope to see first light, and one of the reasons is its ability to study the atmospheres of exoplanets. The idea is to look for biosignatures: things like oxygen and methane. But a new study says that exoplanets with hydrogen in their atmospheres are a good place to seek out alien life.

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When Comets Break Up, the Fragments Can Be Devastating If They Hit the Earth

Comet breakups are a timely topic right now. The interstellar comet 2I/Borisov just broke into at least two pieces. And though that comet is speeding out of the Solar System, never to be seen again, most of them don’t leave the Solar System. Most of them orbit the Sun, and return to the inner Solar System again and again.

A new paper examines the potential hazard to Earth from comets that break into pieces. The author makes the case that comet breakups could have had a hand in shaping the ebb and flow of life on Earth. It could happen again.

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Seriously, Life Really Does Get Around. It was Found in Rocks Deep Beneath the Seafloor

After a lot of hard work spanning many years, a team of scientists have discovered something surprising. They’ve found abundant bacterial life in tiny cracks in undersea volcanic rock in the Earth’s crust. The bacteria are thriving in clay deposits inside these tiny cracks.

This discovery is generating new excitement around the hope of finding life on Mars.

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70 Million Years Ago, Days Were 30 Minutes Shorter, According to this Ancient Clam

Has humanity been doing it all wrong? We’re busy staring off into space with our futuristic, ultra-powerful telescopes, mesmerized by ethereal nebulae and other wondrous objects, and trying to tease out the Universe’s well-kept secrets. Turns out, humble, ancient clams have something to tell us, too.

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