This was
your sky.

The Unusual Tails of Comet Tsuchinshan-Atlas

Comet Tsuchinshan-Atlas displayed an unusual dark streak in its tail in mid-October. This image captured not only its long tail and thin anti-tail, but also this unexpected feature. The reason for the dark streak is still under debate. It might be a plume of dark dust, unusual superposition of tail parts, or a shadow from the coma.