Asteroid that killed dinosaurs stopped a vital process for life on Earth, say experts.

The dinosaurs died 66 million years ago when a city-size asteroid hit a shallow sea off Mexico. How the catastrophic extinction of 75% of Earth's species occurred in the years after the devastating impact is unknown.

Previous study claimed that sulfur released from the impact, which formed the 112-mile-wide (180-kilometer-wide) Chicxulub crater, and wildfire smoke caused a worldwide winter and plummeting temperatures.

A new research published Monday in Nature Geoscience reveals that tiny particles from crushed rock flung into Earth's atmosphere after the impact played a significant effect. This dust obscured the sun so much that plants couldn't photosynthesize for over two years.

Scientists used a new computer model to predict global climate following the asteroid crash. The model was based on published climatic data and sediment samples from the Tanis fossil site in North Dakota that covered a 20-year period following the event.

The Tanis fossil site records what may have been the most important event in Earth's history. A springtime asteroid hit Mexico's Yucatán Peninsula, according to fossilized fish. Other fossils provide unique details of the terrible day.

The latest study's sample contains silicate dust particles that were ejected into the atmosphere before returning to Earth.

The study found that this tiny dust may have lingered in the atmosphere for 15 years after the asteroid hit. Global climate may have dropped by 15 degrees Celsius, experts said.

“It had been long assumed that extreme cold was the main killing mechanism after Chicxulub, but of course photosynthesis cessation is a mechanism,” Senel added.