Asteroid Shower On Earth May Have Triggered Ice Ages, Study Reveals

A major asteroid shower on Earth and the Moon about 800 million years ago may have helped trigger the planet’s ice ages, a new study found. According to the study’s authors, the combined mass of the asteroid shower was greater than that of the impact event that wiped out the dinosaurs.

The new study was carried out by a team of researchers from Japan. Their findings were presented in a new paper published in the journal Nature Communications.

Probably the most well-known impact event on Earth is the Chicxulub impact, which led to the extinction of the dinosaurs 66 million years ago. It is believed that an impact caused by an asteroid as big as the Chicxulub impactor, which was about 6 to 10 kilometers, could happen once every 100 million years.

Unfortunately, due to Earth’s volcanic activities and other geological events, traces of an asteroid impact dating back to over 600 million years ago have been erased. To study the history of asteroid impacts on Earth, the researchers looked to the well-preserved impact craters on the Moon.

For the study, the researchers observed 59 massive craters on the Moon measuring about 12 miles wide using Japan’s Kaguya lunar orbiter. Through their analysis, the researchers learned that many of the massive craters were created about 800 million years ago.

Due to the Moon’s proximity to Earth, the researchers assumed that the asteroids that bombarded the lunar surface also collided with Earth. Through their calculations, the researchers estimated that about 40 to 50 trillion metric tons of space rock material hit Earth during the asteroid shower, which is greater than the total mass of the Chicxulub asteroid.

Based on their timeline, the researchers noted that the asteroid shower occurred right before the Cryogenian period about 635 to 720 million years ago. During this period, Earth experienced its harshest ice ages that almost covered the entire planet.

Like the effect of the Chicxulub impact, the researchers believe that the massive asteroid shower triggered nuclear winters from different parts of the planet. The multiple impacts caused by the asteroids kicked up large amounts of dust and debris into the atmosphere, preventing sunlight from reaching the planet’s surface. The researchers believe this led to global cooling events that caused the ice age.

“From these considerations, I can say that it is not strange that an asteroid shower 800 million years ago might have triggered an ice age, because the total mass 800 million years ago in our study is 10 to 100 times larger than that of the Chicxulub impact and a meteoroid shower 470 million years ago,” the study’s lead author, Kentaro Terada, said, according to Space.com.