Astronomers are excited and have announced that a small and underfunded project has made a world’s first discovery. For the first time, astronomers have been able to detect a 13km radius body at the edge of the solar system. Kilometer size bodies such as this have been predicted to exist for over seven decades, but this is the first time one has been discovered.
Scientists say that these objects are an essential step in the formation of planets in between the small initial amalgamations of dust and ice and the large planets we know today. The Edgeworth-Kuiper Belt is a collection of small celestial bodies that orbit beyond Neptune.
The former planet Pluto is the most famous of these objects. These far away bodies are preserved in the condition of the early Solar System thanks to the cold and dark place they orbit. Objects such as this have been predicted to exist, but have been too distant, small, and dim for even the largest telescopes to observe directly. Astronomers at the National Astronomical Observatory of Japan, led by Ko Arimatsu, used a technique called occultation to make their discovery.
The technique involves monitoring a large number of stars and watching for the shadow of an object to pass in front of the star. The team used small 28cm telescopes on the roof of a school in Japan to monitor 2,000 stars for 60 hours total. When the data was analyzed, they found that an event consistent with a star appearing to dim as if it was blocked by a 1.3km radius object.
The team says that this discovery supports the theory where planetesimals grow slowly into kilometer-sized objects before growing into planets. The group plans to investigate the Edgeworth-Kuiper Belt in more detail in the future, and it wants to examine the Oort Cloud in the future.