NGC 281, nicknamed the PacMan Nebula for its resemblance to the arcade character, is an emission nebula located about 9,500 light-years away in the constellation Cassiopeia.
It spans roughly 48 light-years in radius, nestled in the Perseus Arm of the Milky Way.
The nebula is part of an H II region, meaning it’s a hotbed of star formation, with ionized hydrogen gas glowing due to intense radiation from young stars. 1
Star Cluster IC 1590 sits at the heart of the nebula, containing 20–30 young stars that energize the surrounding gas.
The massive star HD 5005, a blue-white supergiant, plays a key role in sculpting the nebula’s structure through stellar winds and radiation.
Bok globules—dense pockets of dust—dot the region, acting as stellar nurseries where new stars are born.
The nebula’s composition is primarily hydrogen (70–80%) and helium (20–30%), with trace elements like carbon and silicates forming the dust lanes. 1
Discovered in 1883 by Edward Emerson Barnard, NGC 281 was described as “a large faint nebula, very diffuse”.
Its nickname comes from the dust lane that resembles Pac-Man’s open mouth, making it a favorite among astrophotographers and outreach educators.
It floats high above the galactic plane
NGC 281 sits about 1,000 light-years above the Milky Way’s disk, making it part of an “expanding complex of molecular clouds” in the Perseus Arm. That’s unusually elevated for a star-forming region.
It’s home to a quintuple star system
The multiple star system B 1, discovered in the 19th century, includes five stars orbiting each other. The brightest member, HD 5005, is an O6-class supergiant with a surface temperature of 45,000 K—hot enough to ionize the surrounding nebula.
It’s actively forming stars inside Bok globules
These small, dark clouds of gas and dust—called Bok globules—act as stellar incubators, shielding young protostars from external radiation until they’re ready to ignite. 1
1.5 Hours of Ha
3.5 hours of Sii
3.5 hours, of Oiii
Bias and Flats (No Darks)
Total Integration time: ~8.5 hours
Optolog 3nm SHO Filters
Scope: Explore Scientific ED 127mm refractor
Apex ED 0.65x Reducer / Flattener
Camera: ZWO 2600mm
Guide scope: Agena Astro 60mm refractor
Guide camera: ZWO ASI120mm-S
Mount: Losmandy G11G
Beelink Mini PC S Intel 11th Gen
Focuser: ZWO EAF (Electronically Assisted Focuser)
Filter Wheel: ZWO 7 Position
Pegasus Pocket Powerbox Micro
NINA 3.2 used for capture
PixInsight for Processing