(VOA) — The Babylonians thought it was the tail of their goddess Tiamat. Ancient Greeks believed it endowed Hercules with his godlike abilities. But it wasn’t until 1610, when he used his telescope to take a closer look at the Milky Way, that Galileo discovered it was stars — all stars.
And now scientists say that our view of those stars is being washed out by human light sources that continue to brighten our skies.
Losing the “Way”
An international group of scientists used high-resolution satellite data to update the World Atlas of Artificial Sky Brightness, which measures the amount of artificial light that reflects off the atmosphere back down onto Earth. The new data reveals that one-third of humanity is now unable to see the Milky Way, our home galaxy, in the night sky. “We now have a couple generations of people that live in areas that are cut off from viewing of astronomical features,” said Chris Elvidge, a physical scientist at NOAA’s National Centers for Environmental Information. “People no longer have that view and the connection that view gives them to the cosmos.”
As cities expand to accommodate rising populations, their artificial light output increases as well. This obscures the night sky from astronomers, hindering their ability to study the stars.
Artificial lighting also has adverse effects on wildlife. “Every year the research just keeps coming in and the number of different species that are affected by light pollution just keeps growing and growing,” said Cheryl Ann Bishop, communications director for the International Dark-Sky Association.
Ways to bring the lights down
Things aren’t all bad though. Lighting manufacturers are increasingly being asked to produce “dark sky friendly” products such as shielded residential light fixtures and directional flagpole lighting. “We’re not anti-light … we’re not going to go backwards, but we want to make sure it’s done responsibly,” said Bishop.
National parks in remote areas of the United States, particularly in the Southwest, have turned into stargazing destinations.
The Milky Way may be lost to many humans now, but there are people working to bring it back for future generations.
Courtesy of Voice of America