If you think Pluto is the only thing orbiting the sun beyond Neptune, this new chart will set you straight. It shows 132 of the 1,400 "trans-Neptunian objects" that are known to exist in a region that lies 4.5 billion to 7.5 billion kilometers from the sun.
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The objects were all observed by the Herschel Space Observatory, which was launched in 2009 and remained active until 2013. Herschel was constructed and operated by the European Space Agency, which released the chart.
The objects are remarkable for their diversity, not only in size and shape but also the degree to which they reflect light (known among scientists as albedo).
Objects rendered in brown are those with low reflectivity (low albedo), an indication of dark minerals on their surfaces. Objects with high albedo, rendered in white, are likely covered with ice.
Ice or no ice, it's chilly out there.