Ice? Volcano? Or alien life? The discovery of two bright spots on Ceres -- the dwarf planet in the asteroid belt between Mars and Jupiter that happens to be the largest body in that asteroid belt -- has baffled scientists and space enthusiasts.
On May 11, NASA released a sequence of images taken by its Dawn spacecraft. The images were taken from a distance of 8,400 miles (13,600 kilometers).
In this closest-yet view, the brightest spots within a crater in the northern hemisphere are revealed to be composed of many smaller spots. However, their exact nature remains unknown.
"Dawn scientists can now conclude that the intense brightness of these spots is due to the reflection of sunlight by highly reflective material on the surface, possibly ice," said Christopher Russell, principal investigator for the Dawn mission from the University of California, Los Angeles.
These images offer scientists new insights into crater shapes and sizes, and a host of other intriguing geological features on the surface. The image resolution is 0.8 mile (1.3 kilometers) per pixel.
From the moment they were discovered, the two bright spots on Ceres have fascinated scientists and amateur astronomers across the world. What are they and why are they there?
Conspiracy theorists also contributed their own suggestions. UFO and alien enthusiasts said the lights could be evidence of an alien civilization on the dwarf planet.
They scoffed at the idea that the lights were from volcanoes, saying that volcanoes would not give off white light but instead a red and orange light.
Scientists, however, pointed out that cryovolcanoes that form on icy asteroids could actually give off the type of light found in the bright spots on Ceres.
UFO Sighting Daily's Scott Waring said they were either electric lights or massive reflectors on a pair of massive doors leading to an underground alien space station.
He believes the lights are beacons to guide alien space ships approaching the entrance to an underground station.
On May 9, the spacecraft powered on its ion engine to begin the month-long descent toward its second mapping orbit, which it will enter on June 6. In this next phase, Dawn will circle Ceres about every three days at an altitude of 2,700 miles (4,400 kilometers) -- three times closer than the previous orbit.
During this phase, referred to as Dawn's survey orbit, the spacecraft will comprehensively map the surface to begin unraveling Ceres' geologic history and assess whether the dwarf planet is active.
The spacecraft will pause twice to take images of Ceres as it spirals down into this new orbit.
Sicilian astronomer Father Giuseppe Piazzi spotted Ceres in 1801. As more such objects were found in the same region, they became known as asteroids, or minor planets. Ceres was initially classified as a planet and later called an asteroid. In recognition of its planet-like qualities, Ceres was designated a dwarf planet in 2006, along with Pluto and Eris.
Ceres is named for the Roman goddess of agriculture and harvests. Craters on Ceres will similarly be named for gods and goddesses of agriculture and vegetation from world mythology.
Images Courtesy: NASA
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