Another degree further north-east is the well-known and very special variable star R Monocerotis
accompanies a fan-shaped nebula.
The stellar spot at the point of the fan has long been known by the variable-star designation R Monocerotis
. However, the starlike point we see is actually a bright circumstellar shell of gas and dust hiding a young binary star.
Also known as Hubble's Variable Nebula, NGC 2261 fans outward from R Monocerotis
, a dust-shrouded binary star estimated to be 2,500 light- years distant and only 300,000 years old - a mere infant (though a mighty one) in stellar terms.
Embedded in the fan's bright tip is the hazy variable star R Monocerotis. Dark dust clouds moving near the star cast their shadows on the nebula, changing its appearance.
The familiar fan-shaped reflection nebula is a hollow cone resulting from hot gas blowing out perpendicular to R Monocerotis's disk.