A photon from a star billions of light-years away takes no time to reach a telescope. It’s not too little time. There is nothing. That result is not a measured or poetic way of speaking. It comes directly from the mathematics of special relativity, and it points to another strange thing about the nature of … Read more
A Theory of Gravity That Could Rewrite the Universe’s First Minutes The first fraction of a second after the Big Bang has always posed a problem. Physics can explain a lot about the universe once it’s stable and expanding, but in the beginning, when heat and energy were extremes, it was still hard to pin … Read more
In 1916, just a year after Albert Einstein published his general theory of relativity, Karl Schwarzschild used mathematical calculations to show this: If enough mass were packed into a very small volume, then this dense enough mass would create a region where the gravitational force is so strong that nothing, including light, could escape from … Read more
For decades, nuclear activity has been the center of proposals for aeronautical engineering and government studies, always promising, never leaving the laboratory. That changes in 2028. NASA has announced that it will launch the Space Reactor-1 Freedom, described by the agency as the first nuclear-powered interplanetary spacecraft, on its way to Mars before the end … Read more