In this study, the comets have distributions regarding their heliocentric distances where they appear in two regions, Kuiper belt (short period) and Oort cloud (long period). Details here give new information about the entire regions of these comets; the research shows that 54% of comets are nearby asteroid belt, but only 11% are in Kuiper belts and 35 % are from Oort cloud. The research focuses on comets with a nucleus's radius larger than 1 km. The comets with a nuclear radius of 1-10 km have high percentage 51%.
From the results, the maximum comets' radius is found in comet 29P/Schwassmann -Wachmann as roughly 87 km, and also in comet C/2018 N2 (ASASSN) which has radius 88 km. All comets, that have been distributed concerning heliocentric, depend on statistical results to divide new comets' regions versus their radiuses. The results reveal new details of comets' distances from the sun. The distances of 100 comets are shown in Figure (2).
The results show that there is a third comets' region: region (A) found between Mars and Saturn and between Oort cloud and Kuiper belt.
There is one comet like(C/2019 L3 (ATLAS)) that is farther than Alpha Centauri star. Therefore, the comet is restricted by a couple of gravity systems.
