asteroids tagged posts

The majority of stars in the universe will become luminous enough to blast surrounding asteroids into successively smaller fragments using their light alone, according to a University of Warwick astronomer.

Electromagnetic radiation from stars at the end of their ‘giant branch’ phase – lasting just a few million years before they collapse into white dwarfs – would be strong enough to spin even distant asteroids at high speed until they tear themselves apart again and again. As a result, even our own asteroid belt will be easily pulverized by our Sun billions of years from now.

Recent research shows that our planet may have been pummeled with asteroids long before some scientists had previously thought. Welcome to the early solar system. Just after the planets formed more than 4.5 billion years ago, our cosmic neighborhood was a chaotic place. Waves of comets, asteroids and even proto-planets streamed toward the inner solar system, with some crashing into Earth on their way.

Now, a team led by University of Colorado Boulder geologist Stephen Mojzsis has laid out a new timeline for this violent period in our planet’s history...

These images show temperature maps as simulated by MAGHNUM as a result of mud convection, in a medium sized asteroid (above) and a large asteroid (below). Temperatures are shown in degrees Celcius. Credit: Planetary Science Institute

Scientists have long held the belief that planets – including Earth – were built from rocky asteroids, but new research challenges that view. The research suggests that many of the original planetary building blocks in our solar system may actually have started life, not as rocky asteroids, but as gigantic balls of warm mud. Phil Bland, Curtin University planetary scientist, undertook the research to try and get a better insight into how smaller planets, the precursors to the larger terrestrial planets we know today, may have come about.

Planetary Science...

A thankfully rare event: an asteroid hits the Earth. (Visualisations: iStock / Solarseven)

Do mass extinctions, like the fall of the dinosaurs, and formation of large impact craters on Earth occur together at regular intervals? “This question has been under discussion for more than 30 years now,” says Matthias Meier, ETH Zurich’s Institute of Geochemistry and Petrology. As late as 2015, US researchers indicated that impact craters were formed on Earth around every 26 million years. “We have determined, however, that asteroids don’t hit the Earth at periodic intervals,” says Meier, refuting the popular hypothesis.

In the past, researchers have even postulated the existence of a companion star to the Sun...