The maximum brightness at any point of this stream has been measured at 26.7mag/squ arc sec

Interesting that the loop appears slightly square, or flat ended, rather than a smooth curve...?

Paper on this stream here: https://arxiv.org/pdf/2106.04548.pdf

Stellar streams are associations of stars that are grouped into elongated filaments orbiting, usually
in an arc, around a host galaxy. These filaments are thought to be produced when a stream progenitor,
like a globular cluster or a satellite dwarf galaxy, is disrupted by its host galaxy’s tidal forces.
Stars are drawn out from the progenitor into a tidal stream that then orbits the host galaxy, the
progenitor itself may remain connected to the stream, orbit separately, or disrupt entirely.