Dawn Spies Mysterious Luminous Points on Ceres Closely As the End of the Mission (Photos)

NASA's Dawn spacecraft got its best look at the strange dots of light that stain the dwarf. The planet Ceres.

Early last month, Dawn maneuvered into a new orbit around Ceres, an elliptical path that takes the probe 34 km from the dwarf planet to the nearest approach. It's more than ten times closer than Dawn had done during her three years and over in Ceres.

The views of this low altitude are amazing, as have shown new images of the 92 kilometers of Occator Crater. [In Pictures: The Changing Bright Spots of Dwarf Planet Ceres]

The floor of the Occator contains strange bright deposits that Dawn discovered during his approach to Ceres in early 2015. Subsequent observations of the probe revealed that the substance brilliant, which is also found in several places around Ceres, is composed of sodium carbonate. .

Scientists believe that this material was abandoned when salt water evaporated in space. But we do not know exactly where this water comes from. Was it concentrated in tanks near the surface? Or is it snuck up to the surface through deep subterranean cracks?

The photos of the Occator, recently captured by Dawn on June 14 and 22, could illuminate this mystery by painting a more complete picture of the crater's bottom, "The acquisition of these spectacular images was the One of the biggest challenges of the extraordinary extraterrestrial expedition to Dawn, and the results are better than we had hoped for, "said Marc Rayman, chief engineer and project manager at Dawn. Propulsion Laboratory (JPL) in Pasadena, California, said in a statement. "Dawn is like a master artist, adding rich details to supernatural beauty in her intimate portrait of Ceres."

Launched in September 2007, the $ 467 million Dawn mission has an ambitious goal: to orient and study Vesta and Ceres, the two largest asteroid belt between Mars and Jupiter. Vesta and Ceres – respectively 330 km (530 km) and 590 miles (950 km) wide – are building blocks of the planet formation period of the solar system, which explains the name of the mission.

July 2011 to September 2012, when he left for Ceres. The probe arrived on the dwarf planet in March 2015, becoming the first spacecraft to orbit two objects beyond the Earth-Moon system.

Dawn's story-laden mission draws to a close; Last week, the spacecraft fired its super-efficient ion engine for probably the last time. Dawn is poor in hydrazine, the fuel that powers the smaller thrusters to control the orientation of the probe. When the hydrazine will be exhausted in September or so, Dawn will have finished; he will not be able to direct his scientific instruments to Ceres or his antenna to the Earth to communicate.

"Dawn's first views of Ceres have signaled us with a single, blinding light," Carolyn, Dawn's principal investigator, also from JPL, said in the same statement. "Discovering the nature and history of this fascinating dwarf planet during Dawn's long stay in Ceres has been fascinating, and it is particularly fitting that the last act of Dawn provide new sets of data to test these theories."

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