Why and how the asteroid defense might work?

According to the American space agency NASA, there are more than a million asteroids in our solar system alone. More than 20,000 of these remnants of the formation of our solar system are so-called Near Earth Objects (NEOs for short), which in their orbit traverse our Earth’s orbit around the sun. According to astronomers, it is currently known that about 1,000 asteroids and comets have a greater than zero chance of colliding with Earth. The object with the greatest chance of impact is around ten percent.

Planetary Defense Departments Established
For this reason, the space agencies of Russia, Europe and the US have set up planetary defense departments to deal with possible dangers from asteroid impacts. At NASA this is the Planetary Defense Coordination Office, at ESA the Planetary Defense Office.

“Visitors” from space with a diameter of 1000 kilometers, as in the disaster movie “Armageddon”, do not worry scientists too much. “We all know these objects,” said Detlef Koschny of the European Space Agency (ESA). The researcher warns that only about one percent of so-called near-earth asteroids (NEOs) with a diameter of less than a kilometer are known.

Minimal course changes required with early intervention
With its DART (Double Asteroid Redirection Test) mission, NASA has now impressively demonstrated how a potentially dangerous asteroid could potentially be successfully diverted from its collision course with our Earth. It was the first maneuver in space to ever test defenses by significantly altering the course of the celestial body. To send a dangerous asteroid past Earth in an emergency would require only minimal course changes with early intervention.

“DART has provided us with some fascinating data on both the properties of asteroids and the effectiveness of a kinetic impactor (the probe) as a planetary defense technology,” said DART coordination manager Nancy Chabot on the NASA website. They are working hard to “completely understand this first planetary defense test of asteroid deflection”.

It’s already clear that the nature of the asteroid and the amount of “ejecta” (researchers call this the ejecta produced during the impact; ed.) generated when an impactor hits determines how well a “visitor” from the depths is. can be derived from space. During the DART mission, the dust and debris cloud created during the crash amplified the probe’s impact. “Like the air coming out of a balloon and sending it the other way,” explains researcher Chabot.

Job can be significantly shortened
The impact of the DART probe on the asteroid Dimorphos at more than 23,000 kilometers per hour changed its orbit around its big brother Didymos. It was intended to shorten the orbit of the celestial body by up to ten minutes. This goal was clearly exceeded, because it actually took half an hour, NASA calculated from observations with several telescopes.

Experts say the course of action depends on the warning time and size of a dangerous asteroid. The last option they see is to use nuclear weapons “because that’s the greatest amount of available energy you can deposit into an object in the shortest amount of time.” An atomic bomb detonated on the surface of an asteroid that is dangerous to Earth would – according to current knowledge – change its orbit so much that it hurtles past the Earth and thus a catastrophe can be avoided.