The Case of the Mysterious Lights on Dwarf Planet Ceres

ceres
Two views of Ceres are seen in images acquired by NASA's Dawn spacecraft from a distance of about 52,000 miles (83,000 kilometers) February 12, 2015. Courtesy of NASA, via Reuters

It's one of the oldest questions to plague humanity: Are we alone in the universe? Nobody knows the answer (for now), but something weird is out there: Namely, a pair of strange, shiny spots on the dwarf planet Ceres. Even NASA is "puzzled."

CNET reports that NASA's Dawn spacecraft, which has been studying objects in the asteroid belt between Mars and Jupiter since 2007, has detected not one but two mysterious lights as it drifts closer to Ceres. The frozen and rocky dwarf planet, discovered in 1801, is the largest space object lying between Mars and Jupiter's orbit.

On Friday, NASA released a statement confirming that the spacecraft had detected the appearance of peculiar bright spots on the dwarf planet's surface. Recent NASA photographs show two lights: one luminous and another slightly dimmer, becoming smaller and brighter as the spacecraft approaches Ceres's orbit.

"We expected to be surprised; we did not expect to be this puzzled," said principal Dawn mission scientist Chris Russell in the same statement.

One of the lights was spotted from quite far away—83,000 kilometers—and the second from 46,000 kilometers from the planet, according to Ars Technica. Until the spacecraft can zoom in further and produce better images, the source of the lights will likely be unclear.

Scientists are already speculating a variety of possibilities that could explain said lights: One hypothesis suggests that volcanic activity underneath the surface of the protoplanet could be a cause, with the lights stemming from explosions of ice volcanoes. Experts believe that Ceres contains ice underneath its exterior—perhaps even vast freshwater lakes or oceans of liquid, reports Space.com.

Seemingly the most convincing hypothesis thus far purports that when Ceres collides with other space objects in the Mars-Jupiter orbit, cracks could form, causing the icy spots to reflect outward. The problem? Ice reflects almost 100 percent of light as it hits the surface, and these spots are reportedly beaming back only 40 percent of the light cast upon them, according to Ars Technica.

Another camp speculates that the so-called lights are actually magnesium silicates—a kind of mineral that's common in other asteroids—but there's no evidence to support this yet, and while Ceres is technically in the asteroid belt, it bears different properties than asteroids.

And then there's the Twilight Zone-esque hypotheses: Some believe the tiny planet may be "watching us" as we approach it, and the lights are a kind of greeting.

The spacecraft is slated to reach Ceres's orbit on March 6, where it will study the dwarf planet for 16 months, according to CNET. The Dawn will be the first craft to study a dwarf planet this closely, and will take close-up photographs that could solve the case of the mysterious lights. The results could be groundbreaking: In addition to perhaps discovering the origin of the lights, the Dawn may be able to confirm the long-held speculation that Ceres bears more freshwater than Earth, according to The Guardian.

But as Space.com reports, the Dawn isn't physically equipped to search for life on the dwarf planet—so those hopeful for the discovery of alien life forms may have to tide themselves over with an episode of The X-Files or five.