[MUDDOG]

harpoons failed to anchor it to the surface

The Great White Comet.

[Swordmaker]

The Great White Comet.

Uh, nope. Try Great BLACK Comet.

The reconstructed-colour image, taken early October, indicates how dark the comet appears.
On the average, the comet's surface reflects about four per cent of impinging visible light,
making it as dark as coal