NASA attempted to stop a simulated asteroid impact, but failed

LOS ANGELES - A group of scientists and experts, at NASA’s behest, spent a week attempting to stop a fictitious asteroid from crashing into Earth and failed. 

The scientists were invited to a week-long tabletop exercise led by NASA in which they were instructed to use all of Earth’s technological advancements, which were hypothetically at their disposal, in order to stop the space rock from hitting the planet.

The fictitious asteroid, named 2021PDC, had a 5% chance of hitting Earth on Oct. 20, six months from its discovery date, according to the hypothetical mission.

The exercise started on April 26, and each day represented several weeks in the alternate roleplay scenario. 

In the exercise, when the asteroid was first discovered, it was estimated to be roughly 35 million miles away. Scientists then spent the next few "fictional weeks" mapping the asteroid’s path and impact probability. 

Over time, they concluded that the asteroid had a 100% certainty of hitting Earth. The scientists eventually found they simply did not have enough time to stop the asteroid, and in the end, it struck Eastern Europe. 

Some contingency plans to protect Earth from the imminent threat included deploying a nuclear weapon and a flyby reconnaissance space craft to "disrupt" the path of the asteroid, but neither intervention proved effective.

While it remained unclear what type of destruction the fictional asteroid would cause, scientists estimated that the damage radius could range from 114 feet to half a mile in size. 

"If confronted with the 2021PDC hypothetical scenario in real life, we would not be able us to launch any spacecraft on such short notice with current capabilities," the participants said.

All the experts found they could do was evacuate anyone they could who lived in the affected area. 

Exercise participants said that while they were unable to avert the crisis in such a short period of time, it helped them understand how to improve planetary defenses.

RELATED: Skyscraper-sized Asteroid Apophis won’t make contact with Earth for over 100 years, scientists say

"Each time we participate in an exercise of this nature, we learn more about who the key players are in a disaster event, and who needs to know what information, and when," said Lindley Johnson, NASA’s planetary defense officer. "These exercises ultimately help the planetary defense community communicate with each other and with our governments to ensure we are all coordinated should a potential impact threat be identified in the future."

Luckily for most humans, one of the most concerning asteroids, Apophis, which was believed to be on a potential collision course for Earth, is no longer going to be an issue for our big blue planet for another 100 years, scientists say.

After its discovery in 2004, the massive, 1,120-foot-wide space rock, which is basically the Empire State Building turned sideways, is supposed to fly 23,441 miles above Earth's surface on April 13, 2029, as well as in 2036.

Catherine Park contributed to this story.