The gas and dust in a comet’s tail are extremely lightweight.
The tails are created by solar wind rushing past the orbiting comet and blowing material away from the defrosting coma.
When the comet approaches the Sun, the force of the wind pushes the tail out behind the comet.
When the comet is moving away from the Sun, the wind still rushes past it, now sending the comet’s tail out in front.
The head of the comet Flaugergues, also known as the Great Comet of 1811, was bigger than the Sun.
The Great Comet of 1811 was a comet that was visible to the naked eye for around 260 days, a record it held until the appearance of Comet Hale-Bopp in 1997.