Dark energy is one of those cosmological features that we are still learning about. While we can't see it directly, we can most famously observe its effects on the universe—primarily how it is causing ...

In A Nutshell A star 3,260 light-years away dimmed by over 95% for six months, one of the longest stellar blackouts ever ...

For the first time, scientists have watched high‑energy cosmic rays at work deep inside a thick cloud of gas, not just at its outer surface. Using the High Altitude Water Cherenkov Observatory (HAWC), ...