Hubble's Variable Nebula
This is a variable nebula, meaning it is a reflection
nebula that changes its brightness because of the changes in their
star brightness in this case, R Monocerotis. NGC2261 is a classic
example of a variable nebula. The 'fan' is approx 1 light-year across.
The nebula is approx 2500 light-years away from us.
While it was discovered over 200 years ago, Edwin Hubble studdied it extensively and so it was named for him.