The severity of the laboratory test was equivalent to an oblique collision with the rocky surface of the Earth - a comet coming in at an angle of less than 25 degrees from the horizon, rather than head on (perpendicular to the Earth's surface).
One answer might be that the two impacts were, in effect, simultaneous that the objects which created Shiva and Chicxulub were the daughters of a comet that had broken up in space and hit the Earth a few hours apart, as the pieces of comet Shoemaker-Levy 9 hit Jupiter in 1994.
Generally, comet debris can hit Earth's atmosphere at speeds as fast as 110, 000 miles per hour.
Sunday's eye-catching event occurred at the height of the annual Lyrid meteor shower, which happens every April as Earth plows through the dust and debris trailing a comet called Thatcher.
No special equipment was required to watch the shower, which occurs when Earth passes through a stream of dusty debris from the comet Swift-Tuttle.
The material that is burning up in Earth's atmosphere during the Quadrantids likely comes from a comet that broke into fragments centuries ago, NASA says.
CNN: Meteor shower will light up night sky for just a few hours
Stardust is an ambitious but low-cost mission to capture the first samples from a comet, as well as grains of interstellar dust, and return them to Earth.
These were formed when an asteroid or comet smacked into the lunar or Martian surface and threw out debris that fell into Earth's gravitational grasp.
"You can see a few almost every clear dark night if you look long enough, but periodically the Earth passes through a dense swarm of these particles which have only recently come from their parent comet, giving what we call a meteor shower, " he said.
Which is why, after a comet struck Jupiter in 1994, NASA decided to launch a research programme into Near-Earth Objects.
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