What 840 Newly Discovered Minor Planets Beyond Neptune Can Tell Us


The solar system is a tiny but a wonderful familiar corner of the vast dark universe. Celestial neighbors are landed by the spacecrafts, yet its outer reaches are still remarkably unmapped. New 840 minor planets were discovered in the distant and hard-to-explore region beyond Neptune. It is the largest set of discoveries ever made. These icy minor worlds play an important role in knowing the solar system’s history.

As we see it today, the planetary system is not as it formed. The newborn sun was surrounded by a massive disk of material. Encounters with tiny, growing planets – including some of the worlds we’ve just discovered moved the giant planets outward from the sun until they settled into their present locations. Migration of planets also happened in far away systems around many other stars. 

The new discoveries were made as part of a fiveyear project called the OSSOS – Outer Solar System Origins Survey. The observations, conducted from the year 2013 to 2017, they used the imaging camera of one of the world’s major telescopes the Canada-France-Hawaii Telescope on Maunakea in Hawaii. The project looked for faint, slow-moving points of light within eight big patches of sky.

With 840 discoveries made at distances between six and 83 astronomical units (au) – one such unit is the distance between the sun and the Earth. The project gives a very good overview of the many sorts of orbits these “trans-Neptunian objects” have. It successfully tracked all its distant discoveries. In total, more than 37,000 hand-checked measurements of the hundreds of discoveries precisely pinned down their arcs across the sky.

An accompanying software “simulator” (a computer model) was created that provides a powerful tool for testing the inventory and history of the solar system. This will allow the theorists to test out their models of how the solar system came to be in the shape we see it today.

The new icy and rocky objects fall into two different groups, one includes those that reside on roundish orbits in the Kuiper belt. The other consists of worlds that orbit in a careful dance of avoidance with Neptune as it travels around the sun. How these objects got on their present paths is unclear. One explanation that has been put forward is that a yet unseen large planet, sometimes called “Planet Nine”, could be causing them to cluster in space.