According to the most widely-accepted theory, the Moon formed roughly 4.5 billion years ago when a Mars-sized object named Theia collided with Earth (aka. the Giant Impact Hypothesis). This impact threw up considerable amounts of debris which gradually coalesced to form Earth’s only natural satellite. One of the most compelling proofs for this theory is the fact that the Earth and the Moon are remarkably similar in terms of composition.
However, previous studies involving computer simulations have shown that if the Moon were created by a giant impact, it should have retained more material from the impactor itself. But according to a new study conducted by a team from the University of New Mexico, it is possible that the Earth and the Moon are not as similar as previously thought.
Continue reading “New Study Shows the Earth and Moon are not so Similar After All”
For decades, scientists have held that the Earth-Moon system formed as a result of a collision between Earth and a Mars-sized object roughly 4.5 billion years ago. Known as the Giant Impact Hypothesis, this theory explains why Earth and the Moon are similar in structure and composition. Interestingly enough, scientists have also determined that during its early history, the Moon had a magnetosphere – much like Earth does today.
However, a new study led by researchers at MIT (with support provided by NASA) indicates that at one time, the Moon’s magnetic field may have actually been stronger than Earth’s. They were also able to place tighter constraints on when this field petered out, claiming it would have happened about 1 billion years ago. These findings have helped resolve the mystery of what mechanism powered the Moon’s magnetic field over time.
Continue reading “The Moon’s Magnetosphere Used to be Twice as Strong as the Earth’s”
To put it simply, the Earth’s Moon is a dry, airless place where nothing lives. Aside from concentrations of ice that exist in permanently-shaded craters in the polar regions, the only water on the moon is believed to exist beneath the surface. What little atmosphere there is consists of elements released from the interior (some of which are radioactive) and helium-4 and neon, which are contributed by solar wind.
However, astronomers have theorized that there may have been a time when the Moon might have been inhabitable. According to a new study by an astrophysicist and an Earth and planetary scientist, the Moon may have had two early “windows” for habitability in the past. These took place roughly 4 billion years ago (after the Moon formed) and during the peak in lunar volcanic activity (ca. 3.5 billion years ago).
Continue reading “Was There a Time When the Moon was Habitable?”