The Size of PT1

Explanation: This composite image illustrates the size of PT1, a potential New Horizons target Kuiper Belt object (KBO) discovered by the Hubble Space Telescope, relative to the target of the European Space Agency's Rosetta mission target, comet 67P/Churyumov–Gerasimenko ("C-G"), relative to the Cape Cod region of New England. PT1 is much bigger than typical comets like C-G. However typical comets may be fragments of KBOs similar to PT1, and exploration of KBOs like PT1 may thus tell us much about the origin of comets.


Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.