Space and astronomy news
Direct images of exoplanets are rare and lack detail. Future observatories might change that, but for now, exoplanet images don’t tell researchers very much. They merely show the presence of the planets as blobs of light.
But a new study shows that only a few pixels can help us understand an exoplanet’s surface features.
Continue reading “Just a Few Pixels Would let Astronomers Map Surface Features on an Exoplanet Like Oceans and Deserts”
Before the InSight Lander arrived on Mars, scientists could only estimate what the planet’s internal structure might be. Its size, mass, and moment of inertia were their main clues. Meteorites, orbiters, and in-situ sampling by rovers provided other clues.
But when InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) arrived on Mars in November 2018 and deployed its seismometer, better data started streaming in.
Continue reading “Marsquakes are Caused by Shifting Magma”
Something ancient and primordial lurks in Earth’s core. Helium 3 (3He) was created in the first minutes after the Big Bang, and some of it found its way through time and space to take up residence in Earth’s deepest regions. How do we know this?
Scientists can measure it as it slowly escapes.
Continue reading “Primordial Helium, Left Over From the Big Bang, is Leaking Out of the Earth”
Earth formed over 4.5 billion years ago via accretion. Earth’s building blocks were chunks of rock of varying sizes. From dust to planetesimals and everything in between. Many of those chunks of rock were carbonaceous meteorites, which scientists think came from asteroids in the outer reaches of the main asteroid belt.
But some evidence doesn’t line up well behind that conclusion. A new study says that some of the Earth-forming meteorites came from much further out in the Solar System.
Continue reading “The Building Blocks of Earth Could Have Come From Farther out in the Solar System”
Earth formed from the Sun’s protoplanetary disk about 4.6 billion years ago. In the beginning, it was a molten spheroid with scorching temperatures. Over time, it cooled, and a solid crust formed. Eventually, the atmosphere cooled, and life became a possibility.
But how did all of that happen? The atmosphere was rich in carbon, and that carbon had to be removed before the temperature could drop and Earth could become habitable.
Where did all the carbon go?
Continue reading “How did Earth go From Molten Hellscape to Habitable Planet?”
What is humanity? Do our minds set us apart from the rest of nature and from the rest of Earth? Or does Earth have a collective mind of its own, and we’re simply part of that mind? On the literal face of it, that last question might sound ridiculous.
But a new thought experiment explores it more deeply, and while there’s no firm conclusion about humanity and a planetary mind, just thinking about it invites minds to reconsider their relationship with nature.
Overcoming our challenges requires a better understanding of ourselves and nature, and the same is true for any other civilizations that make it past the Great Filter.
Continue reading “Does the Entire Planet Have a Mind of its Own?”
The Moon has orbited Earth since the Solar System’s early days. Anyone who’s ever spent time at the ocean can’t fail to notice the Moon’s effect. The Moon drives the tides even in the world’s most remote inlets and bays. And tides may be vital to life’s emergence.
But if Earth were more massive, the Moon may never have become what it is now. Instead, it would be much smaller. Tides would be much weaker, and life may not have emerged the way it did.
Continue reading “Massive Rocky Planets Probably Don’t Have big Moons”
North Korea released some pictures they say come from their recent missile test. The missile they tested—the intermediate-range Hwasong-12—can reach the U.S. territory of Guam. According to most North Korea observers, the country hopes the tests will bring the U.S. back to the negotiating table.
Continue reading “North Korea Releases Pictures of Earth They Say Were Taken From Space”
Earth has had a long and complex history since its formation roughly 4.5 billion years ago. Initially, it was a molten ball, but eventually, it cooled and became differentiated. The Moon formed from a collision between Earth and a protoplanet named Theia (probably), the oceans formed, and at some point in time, about 4 billion years ago, simple life appeared.
Those are the broad strokes, and scientists have worked hard to fill in a detailed timeline of Earth’s history. But there are a host of significant and poorly-understood periods in the timeline, lined up like targets for the scientific method. One of them concerns UV radiation and its effects on early life.
A new study probes the effects of UV radiation on Earth’s early life-forms and how it might have shaped our world.
Continue reading “The Early Earth was Really Horrible for Life”
A lot has to go right for a planet to support life. Some of the circumstances that allow life to bloom on any given planet stem from the planet’s initial formation. Here on Earth, circumstances meant Earth’s crust contains about 5% iron by weight.
A new paper looks at how Earth’s iron diminished over time and how that shaped the development of complex life here on Earth. Is iron necessary for complex life to develop on other worlds?
Continue reading “Life on Earth Needed Iron. Will it be the Same on Other Worlds?”