Message #261137

[Astra]

 According to NASA, it would take $100 billion to create one milligram of antimatter in a particle accelerator.

Creating a spacecraft engine with the stuff would require finding a way to make tons of it, then harnessing the intense energy from a matter/antimatter reaction. If human beings figured that out, some scientists believe an antimatter engine could propel a spacecraft forward at 70 percent the speed of light.

In that case, it would take a 2,000 years to reach Kepler-452b.

"That is a long time," Charles Liu, an associate in astrophysics at the American Museum of Natural History, told NBC News. "Two thousand years ago, the Roman Empire was around."