For something like 5,000 years, astronomy was the analysis of starlight (some of it reflected). In the mid 20th century, cosmic rays (which are mostly protons) were added to the mix, and then neutrinos. Two years ago came gravitational waves.
That means that, in about a percent of its entire history, astronomy has quadrupled its ontology. A new field, called multimessenger astronomy, has begun characterizing single cosmic events through multiple signal types. Already, light has been paired with gravitational waves and with neutrinos.
It’s a reminder that science advances, not just by seeing better, but by inventing whole new categories of seeing.
Welcome to “The Unseen.”Read the Issue