A New Study of Lunar Rocks Suggests Earth's Water Might Not Have Come from Meteorites

*Meteorites bombard a molten landscape in this illustration of the Late Heavy Bombardment. Credit: NASA Goddard Space Flight Center Conceptual Image Lab*

High-precision oxygen isotopes in Apollo lunar soils reveal a persistent impactor fingerprint, showing that impacts contributed only a tiny fraction of Earth’s water.

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Researchers Match Up 12 Meteorites with the Near-Earth Asteroids They Came From

Every day meteoroids blast through our planet’s atmosphere to hit the ground as meteorites. A team of researchers in Italy traced twelve of them to progenitor asteroids that orbit in near-Earth space. Scientists treasure meteorites because they reveal information about their parent bodies. In an arXiv paper, two Italian researchers—Albino Carbognani and Marco Fenucci—analyze the characteristics of the parent bodies of 20 selected meteorites. They were able to track all but eight back to their parent asteroids. Based on their work, the pair says at least a quarter of meteorites come from collisions that happened in near-Earth space and not in the Main Belt. Meteorites from Near-Earth Asteroids: How They Got Here Many meteorites are chondritic, similar to asteroids in the Main Belt (or came from it). In their paper, the authors point out that progenitor meteoroids (including many that fall to Earth and become meteorites) formed millions of years ago following collisions between main-...

More Data and Machine Learning has Kicked SETI Into High Gear

For over sixty years, astronomers and astrophysicists have been engaged in the Search for Extraterrestrial Intelligence (SETI). This consists of listening to other star systems for signs of technological activity (or “technosignatures), such as radio transmissions. This first attempt was in 1960, known as Project Ozma, where famed SETI researcher Dr. Frank Drake (father of the Drake Equation) and his colleagues used the Robert C. Byrd Green Bank Telescope in West Virginia to conduct a radio survey of Tau Ceti and Epsilon Eridani. Since then, the vast majority of SETI surveys have similarly looked for narrowband radio signals since they are very good at propagating through interstellar space. However, the biggest challenge has always been how to filter out radio transmissions on Earth – aka. radio frequency interference (RFI). In a recent study, an international team led by the Dunlap Institute for Astronomy and Astrophysics (DIAA) applied a new deep-learning algorithm to data collecte...

JWST Takes a Detailed Look at Jupiter’s Moon Ganymede

Nature doesn’t conform to our ideas of neatly-contained categories. Many things in nature blur the lines we try to draw around them. That’s true of Jupiter’s moon Ganymede, the largest moon in the Solar System. The JWST took a closer look at Ganymede, the moon that’s kind of like a planet, to understand its surface better. Ganymede is basically a planet, except it doesn’t orbit the Sun. If it did orbit the Sun instead of Jupiter, it would be indistinguishable from a planet. It has a differentiated internal structure with a molten core that produces a magnetic field. It has a silicon mantle much like Earth’s, and has a complex icy crust with a deep ocean submerged beneath it. It has an atmosphere, though it’s thin. It’s also larger than Mercury, and almost as large as Mars. According to the authors of a new study, it’s an archetype of a water world. But even with all this knowledge of the huge moon, there are details yet to be revealed. This is especially true of its complex surface...

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