A powerful Hubble Space Telescope photographed the most distant active comet ever seen at a huge distance of 2.4 billion kilometers from the Sun (outside of Saturn’s orbit). Slightly heated by the distant Sun, the comet has already begun to develop a fuzzy cloud of dust about 130,000 kilometers wide. This cloud is known as the coma. It envelops the tiny, solid core of frozen gas and dust. This phenomenon is the earliest sign of the activity of a comet.
It’s about the comet C / 2017 K2 (PANSTARRS) or simply “K2”, which lives in the cold outer limits of the solar system, where the ambient temperature is minus 440 degrees Fahrenheit. The orbit of the comet indicates that it came from the Oort Cloud, a spherical region that supposedly contains hundreds of billions of comets. Comets are the ice remains of the early solar system.