The Korea Aerospace Research Institute (KARI) both ended 2022 and started 2023 on a very high note as its first-ever lunar orbiter, Danuri, sent back black-and-white images of the Earth with the Moon’s surface in the foreground that were photographed between December 24 and January 1, KARI announced in a January 3rd statement. Both the images and videos were taken less than 120 kilometers (75 miles) above the Moon’s surface, and will be “used to select potential sites for a Moon landing in 2032,” KARI added in the statement.
Continue reading “South Korea’s Danuri Mission Sends Home Pictures of the Earth and Moon”The Outer Solar System Supplied a Surprising Amount of Earth’s Water
In a recent study published in Science, a team of researchers at Imperial College London examined 18 meteorites containing the volatile element zinc to help determine their origin, as it has been long hypothesized that Earth’s volatiles materials, including water, were derived from asteroids closer to our home planet. However, their results potentially indicate a much different origin story.
Continue reading “The Outer Solar System Supplied a Surprising Amount of Earth’s Water”NOAA’s New Weather Satellite is Operational, and its Pictures of Earth are Gorgeous

You’d have to be in some kind of sense-of-wonder-repressed coma not to appreciate satellite images of Earth. If you are, then images from the NOAA’s newest satellite might pull you out of it.
And they’re only a taste of the fascinating images that it will provide.
Continue reading “NOAA’s New Weather Satellite is Operational, and its Pictures of Earth are Gorgeous”Earth’s Water is 4.5 Billion Years Old

The origin of Earth’s water has been an enduring mystery. There are different hypotheses and theories explaining how the water got here, and lots of evidence supporting them.
But water is ubiquitous in protoplanetary disks, and water’s origin may not be so mysterious after all.
Continue reading “Earth’s Water is 4.5 Billion Years Old”Asteroids Didn’t Create the Moon’s Largest Craters. Left-Over Planetesimals Did

The Moon’s pock-marked surface tells the story of its history. It’s marked by over 9,000 impact craters, according to the International Astronomical Union (IAU.) The largest ones are called impact basins, not craters. According to a new study, asteroids didn’t create the basins; leftover planetesimals did.
Continue reading “Asteroids Didn’t Create the Moon’s Largest Craters. Left-Over Planetesimals Did”OK, Artemis. Now You’re Just Showing Off. A Stunning View of the Moon Eclipsing Earth From the Orion Spacecraft
Have you ever seen a lunar eclipse of the Earth from the far side of the Moon? Now we have.
On Monday (November 28, 2022) NASA’s Orion spacecraft streamed back live video showing the Earth and Moon right next to each other, followed by a stunning view of the Moon eclipsing the Earth.
What a time to be alive! Image editor Kevin Gill might have said it best:
Continue reading “OK, Artemis. Now You’re Just Showing Off. A Stunning View of the Moon Eclipsing Earth From the Orion Spacecraft”Mars Once had Enough Water for a Planet-Wide Ocean 300 Meters Deep

Today, Mars is colloquially known as the “Red Planet” on a count of how its dry, dusty landscape is rich in iron oxide (aka. “rust”). In addition, the atmosphere is extremely thin and cold, and no water can exist on the surface in any form other than ice. But as the Martian landscape and other lines of evidence attest, Mars was once a very different place, with a warmer, denser atmosphere and flowing water on its surface. For years, scientists have attempted to determine how long natural bodies existed on Mars and whether or not they were intermittent or persistent.
Another important question is how much water Mars once had and whether or not this was enough to support life. According to a new study by an international team of planetary scientists, Mars may have had enough water 4.5 billion years ago to cover it in a global ocean up to 300 meters (almost 1,000 feet) deep. Along with organic molecules and other elements distributed throughout the Solar System by asteroids and comets at this time, they argue, these conditions indicate that Mars may have been the first planet in the Solar System to support life.
Continue reading “Mars Once had Enough Water for a Planet-Wide Ocean 300 Meters Deep”What’s the Best Mix of Oceans to Land for a Habitable Planet?

Earth is about 29% land and 71% oceans. How significant is that mix for habitability? What does it tell us about exoplanet habitability?
Continue reading “What’s the Best Mix of Oceans to Land for a Habitable Planet?”Volcanoes are the worst. They’ve caused extinctions on Earth, and probably killed Venus

Is there anything good about volcanoes? They can be violent, dangerous, and unpredictable. For modern humans, volcanoes are mostly an inconvenience, sometimes an intriguing visual display, and occasionally deadly.
But when there’s enough of them, and when they’re powerful and prolonged, they can kill the planet that hosts them.
Continue reading “Volcanoes are the worst. They’ve caused extinctions on Earth, and probably killed Venus”Three New Potentially Hazardous Asteroids Discovered, Including a big one That Measures 1.5 km Across

An asteroid 1.5 km across is no joke. Even a much smaller one, about the size of a house, can explode with more power than the first nuclear weapons. When an asteroid is greater than 1 km in diameter, astronomers call them “planet-killers.” The impact energy released from a planet-killer striking Earth would be devastating, so knowing where these asteroids are and where they’re headed is critically important.
Our defensive capability against asteroid strikes is in its infancy, so advance notice of asteroids that could cross Earth’s orbit is critical. We’ll need time to prepare.
Continue reading “Three New Potentially Hazardous Asteroids Discovered, Including a big one That Measures 1.5 km Across”