CURRENT AFFAIRS

Detailed explanation-1: -Using a new statistical method called astrochronology, astronomers peered into Earth’s deep geologic past and reconstructed the planet’s history. This work revealed that, just 1.4 billion years ago, the moon was significantly closer to Earth, which made the planet spin faster.

Detailed explanation-2: -Bye! The moon used to be closer. When it first formed, about 4.5 billion years ago, molded out of rocky debris that had been floating around Earth, the moon orbited 10 times nearer to the planet than it does today.

Detailed explanation-3: -The moon’s distance from Earth varies throughout its monthly orbit because the moon’s orbit isn’t perfectly circular. Every month, the moon’s eccentric orbit carries it to apogee – its most distant point from Earth – and then, some two weeks later, to perigee – the moon’s closest point to Earth in its monthly orbit.

Detailed explanation-4: -At the time of formation it was about 4 Earth-radii distant-that is, it was orbiting about 15, 000–20, 000 miles away, as opposed to the current average distance of 238, 000 miles.