* "Material with a long tail" This suggests something like a comet. Comets are icy bodies with a long, dusty tail that forms as they get close to the sun.
* "Travels around the sun" This indicates an object orbiting the sun, which is a characteristic of comets.
Therefore, the answer is likely a comet.
However, it's impossible to give a specific mass without knowing which comet is being referred to. Comets vary greatly in size.
Let me know if you'd like to try another riddle!
