// Workers AI · dad joke modeIs HH 222 a star system? Does it have a twin: HH 222-2?

HH 222

Nebula
Herbig–Haro object
European Southern Observatory image of HH 222
Observation data: J2000.0 epoch
Right ascension	05h 35m 41.00s
Declination	−06° 22′ 60.0″
Distance	1,500 ly
Constellation	Orion
Designations	HH 222

HH 222 (also known as the Waterfall Nebula and Orion Streamers) is a prominent Herbig–Haro object located in the Orion molecular cloud complex. It is characterized by its elongated, cascade-like structure resembling a flowing waterfall, formed by ionized gas streams interacting with surrounding molecular clouds.

Structure

HH 222 is a giant, curved filament of shocked gas, stretching in a sinuous path that evokes the appearance of cascading water. The structure converges toward a bright, non-thermal radio source in its upper left region, with fainter parallel streams enhancing the waterfall illusion. Spectroscopic analysis reveals high-velocity outflows, indicative of shock fronts where material reaches speeds of hundreds of km/s.

The nebula is embedded in a dusty environment, with the surrounding L1641 cloud obscuring parts of its extent in optical wavelengths. Infrared and radio observations have been crucial for mapping its full morphology and kinematics.

Formation

HH 222 is classified as a giant Herbig–Haro flow, arising from collimated outflows ejected by young, low-mass stars during their protostellar phase. Detailed studies in 2013 identified its origin in the quadruple star system V380 Orionis, a multiple system of young stars approximately 0.3 parsecs from the nebula's head.