NOUN
- the distance light travels in a vacuum in one second; approximately 300,000 kilometers
How To Use light second In A Sentence
- We'll accelerate until we're about half a light second from the planet, then we'll cut engines and slingshot around for another boost in speed.
- The EPOXI spacecraft is indeed in interplanetary space; during the DINET test its distance from Earth varied between 81 and 49 light seconds, which is around 50 times the distance to the Moon, around 1/4 of the distance to Mars at closest approach, and around 1/20 of the maximum distance to Mars. Extending Cyberspace Into Outer Space - NASA Watch