We know that deep space is dark, but just how dark is it? Or, put another way, how bright is it? And how much of that brightness comes from galaxies? Astronomers have gotten a clearer answer to those questions, thanks to observations sent back from billions of miles away.
Nine years after its history-making flyby of Pluto, NASA’s New Horizons spacecraft measured the brightness of the distant universe from a vantage point in deep, dark space.
“If you hold up your hand in deep space, how much light does the universe shine on it?” Marc Postman, an astronomer at the Space Telescope Science Institute in Baltimore, asked today in a news release. “We now have a good idea of just how dark space really is.”