The Earth’s magnetic field is produced by the geodynamo, the rapid motion of huge quantities of liquid iron alloy in the Earth’s outer core. A team of French researchers suggests that elastic deformation of our planet’s mantle due to tidal effects caused by the Moon — overlooked until now — transfers energy to the Earth’s outer core, keeping the geodynamo active.
Did the “Man in the Moon” look different from ancient Earth? New NASA-funded research provides evidence that the spin axis of the Moon shifted by about five degrees roughly three billion years ago. The evidence of this motion is recorded in the distribution of ancient lunar ice, evidence of delivery of water to the early solar system.
The Moon was formed by a violent, head-on collision between the early Earth and a “planetary embryo” called Theia (pronounced THAY-eh) approximately 100 million years after the Earth formed, UCLA scientists reveal. This new research also refutes the work of a team of German scientists who, in 2014, reported that the Moon also has its own unique ratio of oxygen isotopes, different from Earth’s.
About 600 miles from Earth’s surface is the first of two doughnut-shaped electron swarms, known as the Van Allen Belts. Understanding the shape and size of the belts, which can shrink and swell in response to incoming radiation from the Sun, is crucial for protecting technology in space. A new study of data from NASA’s Van Allen Probes reveals that the story is a complex one.
NASA’s Lunar Reconnaissance Orbiter (LRO) recently captured a unique view of Earth centred just off the coast of Liberia from the spacecraft’s vantage point in orbit around the Moon, about 83 miles above the crater Compton, which is located just beyond the eastern limb of the Moon, on the lunar farside.
Dark matter is an invisible, mysterious substance that makes up about 27 percent of all matter and energy in the universe. A new NASA study publishing this week proposes that when a stream of dark matter particles goes through a planet, the planet’s gravity bends and focuses the particles into an ultra-dense filament, or “hair,” of dark matter. In theory, there should be many such hairs sprouting from Earth.
Astronomers believe that the Earth-Moon system was created in a giant impact 4.5 billion years ago. Southwest Research Institute scientists combined dynamical, thermal, and chemical models of the Moon’s formation to explain the relative lack of volatile elements like potassium, sodium, and zinc in lunar rocks, when compared to those of Earth.
Using a new process in planetary formation modelling, where planets grow from tiny bodies called “pebbles,” Southwest Research Institute scientists can explain why Mars is so much smaller than Earth. This same process also explains the rapid formation of the gas giants Jupiter and Saturn, as reported earlier this year.
Earth came early to the party in the evolving universe. According to a new theoretical study, when our solar system was born 4.6 billion years ago only eight percent of the potentially habitable planets that will ever form in the universe existed. And, the party won’t be over when the Sun burns out in another 6 billion years. The bulk of those planets — 92 percent — have yet to be born.
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