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F our and a half billion years ago, a star exploded and a cloud of dust spewed into the universe. As it collapsed, the cloud began to spin, and particles began to clump together into planets and moons. Hotter planets fell into the centre of the disk and, at the very centre, our sun was born. Small, icy planets like Pluto sat on the rim of the great spinning disk. One of those small, icy planets is the dwarf planet Ceres.

A week ago, on 6 March, NASA’s Dawn spacecraft entered orbit around Ceres, a relic from our solar system’s explosive beginnings. At 1000 kilometres across, Ceres is one of the largest planetary bodies in our solar system that hasn’t yet been explored, and is the first dwarf planet explored by a spacecraft.

Since Ceres was born with the birth of the galaxy, it’s considered a “protoplanet”. Like studying a fossil, investigating Ceres’ composition and processes is like looking through a portal to the dawn of time to get a glimpse of how the universe operated at its very birth.

Better yet, Ceres likely harbours water, and may even host microbial life.

Planetary scientists at NASA’s Jet Propulsion Laboratory (JPL) are nearly certain that they will find water in the form of a briny sea of ice when they land on Ceres. The idea came when planetary scientists spotted “unusually bright spots” on a 92 kilometre-wide crater in Ceres’ northern hemisphere. They believe the bright spots come from light reflected off frozen water.

As in Columbus’ days, when ships sailed the oceans for years in hope of discovering new lands, planetary exploration requires long journeys. Ceres was spotted from Earth in 1801, but it isn’t until now that a spacecraft is nearing the dwarf planet, 4.9 billion kilometres away from earth.

In fact, the Dawn spacecraft took off in September 2007 and has been roaming the universe for seven years — before it took off for Ceres, it visited Vesta, the second-largest rock in the asteroid belt. Like Mars, Vesta turned out to harbour watery minerals — most likely, they came from a smaller, water-rich asteroid that crashed into Vesta and left mineral residue in its crust.

The plan on Ceres is to analyse minerals and conduct planetary geology, similar tasks to those conducted on Mars or Vesta. Dawn will lower down onto the planet’s surface over the next few months and will stay for 16 months, with a planned departure on 16 June to fly home.

Hopefully, Dawn will bring back some clues into our solar system’s beginnings, and maybe even a further clue in the ongoing quest to discover extraterrestrial life.