Astronomers Spot Ghostly Light Across Solar System

The deep darkness of space may not be so dark in our solar system.

Astronomers analyzed more than 200,000 images from NASA’s Hubble Space Telescope, performing tens of thousands of measurements in an attempt to locate a residual background glow in the night sky. The project is called Skysurf, and it’s based at Arizona State University and involves researchers there and around the world.

The team harvested data from the images and then subtracted the glow from planets, stars, galaxies and even ethereal zodiacal light, which is light reflected from dust in our solar system.

After taking all of this into account, there was still a tiny bit of glow or “ghost light,” which the researchers describe as equivalent to the glow of 10 fireflies spread across the night sky.

“We believe this is a local phenomenon that does not come from far outside the solar system,” ASU researcher Tim Carleton explained in a statement Thursday. “This may be a new piece of solar system content that has been hypothesized but not measured quantitatively so far.”

One main explanation is that the glow comes from a previously unknown sphere of dust left behind by countless comets traveling through the solar system in all directions.

The discovery is documented in a handful of studies. Two were published in Astronomical Journal and another in Astrophysical Journal Letters.

One of the studies was led by ASU’s Rogier Windhorst, who points out that more than 95% of the photons in the Hubble images come from distances on our side of the universe, less than 3 billion years- earth light.

“Since the very early days of Hubble, most Hubble users have rejected these photons from the sky because they are interested in faint discrete objects in Hubble images, such as stars and galaxies,” Windhorst said. “But those sky photons contain important information that can be extracted through Hubble’s unique ability to measure low levels of light with high precision over its three-decade lifespan.”

And among that information, Windhorst and others may have just located a whole new piece of ethereal architecture underlying our entire solar system. If you consider a light but pervasive layer of dust to be architecture, sure.