Where Pluto fits in the family of ‘not-planets’

Emily Lakdawalla at The Planetary Society website has lost no time dropping in the best-resolution image available from New Horizons of Pluto into her excellent graphic – a scale image montage showing how the dwarf planet fits with the solar system’s similar-sized worlds – the major moons and the biggest asteroids.

Describing these as the “not-planets” Lakdawalla writes:

The solar system contains dozens of objects that are large enough for self-gravity to make them round, and yet are not considered planets. They include the major moons of the planets, one asteroid, and many worlds in the Kuiper belt. The ones that we have visited with spacecraft are shown here to scale with each other. A couple of items on here are not quite round, illustrating the transition to smaller, lumpier objects.

Bill Condie

Bill Condie

Bill Condie is a science journalist based in Adelaide, Australia.

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