One comet for which he calculated an orbit had been discovered by Messier. Lexell found that it had a period of five and a half years which made it the first comet to be discovered with a short period.
Isa buntala na kung saan siya kinakalkula ng isang orbita had been natuklasan sa pamamagitan ng Messier. Lexell nahanap na ito ay isang panahon ng limang taon at kalahati na kung saan ginawa ito ang unang buntala na natuklasan sa isang maikling panahon.