The farthest reaches of our solar system remain the most mysterious areas around the sun. Solving the mysteries of the outer solar system could shed light on how the whole thing emerged - as well as how life on Earth was born.
Why the rainbow of colors in the Kuiper belt?For instance, the Kuiper belt past Neptune is currently the suspected
home of comets that only take a few decades or at most centuries to complete their solar orbits - so-called "short-period comets." Surprisingly, Kuiper belt objects "show a wide range of colors - neutral or even slightly blue all the way to very red," said University of Hawaii astrophysicist David Jewitt.
The color of an object helps reveal details about its surface composition. It remains a mystery why Kuiper belt objects show a much wider range of color - and thus surface composition - than other planetoids, such as the asteroids.
Some researchers had suggested volcanic activity could have led to all these colors - "absurd in the context of 100-kilometer-sized (60-mile) bodies," Jewitt said, as volcanism needs something bigger.