Celestial Discovery! Solar System’s Third Largest Dwarf Planet ‘2007 OR10’ Has A Moon

The third largest dwarf planet in the solar system, called 2007 OR10 that is located in the Kuiper Belt beyond Neptune, has a moon orbiting it. The discovery shows that most of the known dwarf planets, in this frigid zone, that are larger than 965 kilometers have a natural satellite. Moreover, these moons give an idea about how such natural satellites formed when the solar system was young.

The new moon was discovered with the help of three space observatories that included the Hubble Space Telescope, SpaceFlight Insider reported. The research team spotted the moon in Hubble’s archival images of 2007 OR10. However, the astronomers were first tipped off about the presence of a moon by Kepler Space Telescope’s observations. Incidentally, the Kuiper belt located on the outskirts of the solar system is the icy debris left over from our star system’s formation 4.6 billion years ago.

"The discovery of satellites around all of the known large dwarf planets -- except for Sedna -- implies that at the time these bodies formed billions of years ago, collisions must have been more frequent, and that is a constraint on the formation models," study lead author Csaba Kiss said, according to The Times of India. "If there were frequent collisions, then it was quite easy to form these satellites." According to the researchers, the celestial objects possibly collided with each other due to the crowded region they inhabited.

Incidentally, the third largest dwarf planet has a slow rotation period of 45 hours, whereas the typical rotation period of objects in the Kuiper Belt is under 24 hours. This phenomenon made the research team take a closer look at the images captured by Hubble because they suspected that the slower rotation period could be the result of a moon’s gravitational tug. However, the researchers missed out on noticing the moon during the first investigation because it was very faint in the images. Two different Hubble images captured a year apart finally helped the astronomers detect the moon.