NASA probe approaches Ceres as we explore the last corners of our solar system

This week, NASA’s Dawn spacecraft snapped the best picture yet of Ceres, the largest object in the Asteroid Belt and one of the last unexplored places in our solar system.

The historic image was taken about 237,000 kilometers away from Ceres, as the probe prepares to become the first human-made spacecraft to visit a dwarf planet. The resolution of pictures we are seeing has already surpassed those by the Hubble Space Telescope by 30 per cent. That’s because the Hubble telescope is a whopping 241 million kilometres away.

"We are already seeing areas and details on Ceres popping out that had not been seen before," said Carol Raymond, deputy principal investigator of the Dawn mission at NASA’s Jet Propulsion Laboratory. "For instance, there are several dark features in the southern hemisphere that might be craters within a region that is darker overall."

But the best is yet to come, because Dawn is scheduled to enter orbit around Ceres on March 6 and will get views of the alien surface from as low as 300 kilometres over the course of the rest of the year.

"Data from this mission will revolutionize our understanding of this unique body," Raymond said. "Ceres is showing us tantalizing features that are whetting our appetite for the detailed exploration to come."

Ceres orbits the Sun between Mars and Jupiter in the main asteroid belt, and has a diameter of about 950 kilometres. Tantalizing clues in recent years have suggested that the dwarf planet may harbour a ocean of liquid water under its icy mantle.

And while Ceres may not only offer an oasis for possible life beneath its surface, the worldlet could also offer future deep space human-missions a convenient refuelling stop on the way to the outer solar system.

Humans have surveyed much of the solar system, but after Ceres, the last remaining unexplored region of our Sun’s empire will be the outer fringes of the solar system – beyond the last great planet Neptune.

Another first in space exploration will take place in July when, after travelling over 3 billion miles over 9 years, the piano-sized New Horzions spacecraft arrives at the last unknown world – Pluto.

This frozen little world and its retinue of five moons lie at the edge of the solar system, and on the list of things scientists plan to do are characterizing the global geology and topography of Pluto and its large moon Charon, mapping their surface compositions and temperatures, examining Pluto’s atmospheric composition and structure, studying Pluto’s smaller moons and searching for new moons and rings.

After swinging through the dwarf planet’s realm next summer, New Horizons will continue its lonely journey on towards the Kuiper belt, a ring of Pluto-like frozen bodies circling the Sun at the edge of the known solar system.

The New Horizons mission will begin to reveal the characteristics of the objects within a region called the Kuiper Belt, which wasn’t discovered until the 1990s. In it are countless dwarf planets – lots. They’re the most common type of body in the solar system, and yet we know nothing about them.

Many in the space community are calling the Pluto mission the last great exploratory mission of our solar system, a modern equivalent of the Voyager mission of the 1980s that gave us our first detailed looks at Jupiter, Saturn, Uranus and Neptune.

Now this new mission is the first opportunity in a generation to discover not only a new planetary system, but also the vast outer reaches of the solar system.