centauri-dreams.org

j6AEn TIL a propulsion system travelling at light speed is possible with our current knowledge, but the amounts of energy required are too great for it to be feasible. A spacecraft with a 100m radius would need an amount of energy that is 100s of times Jupiter's mass just to maintain the speed of light.
BjDy TIL there is a star “Przybylski’s star” with elements that are thought to be impossible to exist in nature in its light spectrum. gadolinium, einsteinium, etc. Many theories say it’s aliens dumping them there as a signal of their existence