Great comet of 1843, illustration. The Great Comet of 1843, formally designated C/1843 D1 and 1843 I, was a long-period comet that became very bright in March 1843 (it is also known as the Great March Comet). It was discovered on 5th February 1843, and rapidly brightened to become a great comet. It was a member of the Kreutz Sungrazers, a family of comets resulting from the breakup of the parent comet X/1106 C1 into multiple fragments in about 1106. These comets pass extremely close to the surface of the Sun and often become very bright as a result.