This was
your sky.

Earth, Clouds, Sky, Comet Credit and Copyright:

Does a comet's dust tail always trail behind it? Comets shed gas and dust in all directions. Sunlight, however, pushes these small ice and dust particles. When a comet approaches the Sun, sunlight slows these particles, so they orbit behind it. But when the comet moves away, sunlight speeds them up, making them orbit in front of the comet.