Asteroid impact, source of moon’s magnetic anomalies

A new study says the magnetic anomalies found on the moon are remnants of an ancient gigantic asteroid that hit the lunar surface approximately 4 billion years ago.

The study published in the journal Science indicates that the asteroid collision left behind, at the moon’s South Pole, a gigantic crater which is one of the largest-known impact craters in the solar system.

The 2,400 kilometer-diameter crater helped scientists to provide the answer to the question regarding the reasons behind the existence of magnetic fields on some parts of the lunar crust.

Scientists have been able to find evidence that the moon generated its magnetic field long time ago, but the evidence was not strong enough to explain the observed anomalies.

"The conundrum has always been that the magnetism we see on the moon is not correlated with any surface geology,”‌ said co-author Sarah Stewart-Mukhopadhyay.

“The theory that has been most commonly cited to explain it is an 'impact-induced field,' in which an impact concentrates and amplifies the moon's magnetic field,”‌ she added. “But it was difficult to test. People have tried to model it, but it is right at the edge of what could work.”‌

"We have a simpler idea. Because the fields in this area are stronger than those found in any normal lunar rocks, our hypothesis is that it isn't lunar material. We know the magnetic properties of asteroidal material are much higher than that of the moon. It is possible that metallic iron from an asteroid could have been magnetized by the impact, and deposited on the moon," Stewart-Mukhopadhyay explained.

In the next stage of their study, researchers ran several sophisticated computer codes in order to model the impact and the formation of the crater.

"We modeled a number of scenarios using faster or slower impacts and more shallow or more vertical angles. Each time, the model produced similar results to what we see on the moon." Stewart-Mukhopadhyay added.

Source: presstv.com