Scientists puzzled by asteroids that hit Earth 35 million years ago and seemingly left no climate impacts

Modeling studies of the larger Chicxulub impact, which killed off the dinosaurs, also suggest a shift in climate on a much smaller time scale of less than 25 years,

Wade said

What is remarkable about our results is that there was no real change following the impacts. We expected the isotopes to shift in one direction or another, indicating warmer or cooler waters, but this did not happen,

University College London Professor Bridget Wade said

It also has to have an absolute brightness of 22.0 or less (lower values of the magnitude are brighter = larger objects), i.e. an asteroid (or comet) that would cause significant regional damage if it hit the Earth,

Barstow added

Meteorites are actually cold by the time they hit the ground, despite the outside being hot as it goes through the atmosphere there's no time for the whole thing to heat up, only the very outer layer, and the heat is dispersed very quickly – well before it hits the ground,

Annemarie E. Pickersgill, a meteorite-impact scientist at the University of Glasgow, told Newsweek

Martin Barstowprofessor of astrophysics and space science

A potentially hazardous asteroid (PHA) is one that has an orbit intersecting the Earth's orbit around the Sun by less than 0.05 astronomical units (1 AU is the distance to the Sun), that's just over 4.5 million miles,

Martin Barstow, a professor of astrophysics and space science at the University of Leicester in the U.K., previously told Newsweek

Asteroid #C0WEPC5 (temporary designation) entered Earth's atmosphere at 16:15 UTC/17:15 CET, creating a fireball over Yakutia witnessed by people in the region,

ESA said in the post

Our study would not have picked up shorter-term changes over tens or hundreds of years, as the samples were every 11,000 years,

Wade said

The fossils are about the size of a grain of sand (0.5 mm) and we can separate them into different species under the microscope,

Wade said

We were expecting some kind of climate perturbation, most likely cooling to result from the impacts, so we were surprised to find no climatic response,

Bridget Wade, the study's co-author, told Newsweek

These large asteroid impacts occurred and, over the long term, our planet seemed to carry on as usual."

She added in a statement

Thanks to observations from astronomers around the world, our alert system was able to predict this impact to within +/- 10 seconds,

according to the agency

It's a win for science, and [for] anybody who happens to be in Siberia this evening, ... There's something to take your mind away from the no doubt quite chilly temperatures.

Fitzsimmons told New Scientist, adding

It’s a small one, but it will still be quite spectacular, ... It will be dark over the impact site and for several hundreds of kilometres around there’ll be a very impressive, very bright fireball in the sky.”

he told the outlet, adding