Blowing up asteroid to block sun could cool climate, scientists say

An illustration showing an asteroid collision between Mars and Jupiter that occurred 470 million years ago and produced the dust that led to an ice age on Earth.
An illustration showing an asteroid collision between Mars and Jupiter that occurred 470 million years ago and produced the dust that led to an ice age on Earth.PHOTO: REUTERS

STOCKHOLM (DPA) - Earth was plunged into an ice age 470 million years ago after the break-up of an asteroid created a giant dust cloud that blocked sunlight, new research released on Wednesday (Sept 18) found. Now, scientists are looking to create a similar man-made event to cool our climate today.

The research from scientists at Lund University in Sweden and Chicago's Field Museum found that the "unexpected discovery" could be relevant for tackling global warming if we fail to reduce carbon dioxide emissions.

"Our results show for the first time that such dust at times has cooled Earth dramatically," professor of geology Birger Schmitz of Lund University, the leader of the study, said.

For over a decade, researchers have discussed different artificial methods to cool the planet in case of a major climate catastrophe.

They are now looking at the possibility of placing asteroids, much like satellites, in orbits around Earth to continuously release fine dust and partly block sunlight.

"It is analogous to standing in the middle of your living room and smashing a vacuum cleaner bag, only at a much larger scale," Prof Schmitz explained.

For 25 years, there was a different hypothesis in terms of what led to the ice age. The study states that 470 million years ago, a 150km asteroid between Jupiter and Mars was crushed, and the dust spread through the solar system, causing a dust cloud to partially stop sunlight from reaching Earth.

This led to the climate changing from "being more or less homogeneous to becoming divided into climate zones", and subsequently created higher levels of biodiversity.