Dinosaurs extinct due to fine dust

Sixty-six million years ago, a meteorite struck and created a nearly 200-km-long crater in Mexico's Yucatán Peninsula. As huge amounts of sulphur particles and soot entered the atmosphere in the process, light and heat from the sun were blocked. The planet entered an exceptionally bleak, dusty and cold era.

But while sulphur was problematic, silicate dust with a much finer grain size than previously thought ensured that the dinosaurs' days were numbered. It is possible that dust continued to swirl in the atmosphere for up to 15 years after impact. The result? The Earth's temperature may have plummeted by as much as 15°C and, for two years, all photosynthesis failed and food became scarce. Animals and plants that could not adapt to the changed conditions died out en masse. This is what the VUB's Archaeology, Environmental Changes & Geo-Chemistry Research Group, the Royal Observatory of Belgium (ROB), the Royal Belgian Institute of Natural Sciences (RBINS) and KU Leuven infer from their examination of dust particles found at a geological site in the North American state of North Dakota.

Research at other major geological sites in the US and perhaps Europe is yet to confirm that theory. Science would also like to confirm whether the meteorite was an asteroid or a comet.