The Bubble called PN G75.5+1.7 is about 4000 ly from us and is about 5 light-years across.
Its apparent diameter is 260 arc-seconds.

It can be seen here neighboring the Crescent nebula - the Bubble can be seen just Right to the center of the frame.

Imaged with Boren-Simon 10" F/2.8 POWERNEWT Astrograph.
SBIG ST8300M camera with FW5 filterwheel and BAADER LRGB filters.

Hydrogen Alpha image for 80 minutes Bin 1 (8X10 min)
Imaged from my home in Gan-Yavne Israel