HOPS 383

Infrared images from instruments at Kitt Peak National Observatory (left) and NASA's Spitzer Space Telescope document the outburst of HOPS 383, a young protostar in the Orion star-formation complex. The background is a wide view of the region taken from a Spitzer four-color infrared mosaic.
Observation data Epoch J2000.0      Equinox J2000.0
Constellation	Orion
Right ascension	5h 35m 29.81s
Declination	−4° 59′ 51.1″
Characteristics
Evolutionary stage	Class 0 protostar
Astrometry
Distance	1,400 ly (420 pc)
Other designations
HOPS 383
Database references
SIMBAD	data

HOPS 383 is a Class 0 protostar. It is the first Class 0 protostar discovered to have had an outburst,^[1] and as of 2020, the youngest protostar known to have had an outburst.^[1] The outburst, discovered by the Herschel Orion Protostar Survey (HOPS) team, was first reported in February 2015 in The Astrophysical Journal Letters.^[2]

HOPS 383 had an outburst between 2004 and 2006 (a "dramatic mid-infrared brightening"); the increase in magnitude was detectable at the 24 μm (35 times increase) and 4.5 μm, and was also detectable at the submillimetre.^[3]: 2 After 6 years, observations showed no signs of fading.^[3]: 1

The Chandra X-Ray Observatory detected an X-ray flare from HOPS 383 in December 2017.^[4] This was the first detection of X-rays from a Class 0 protostar that will evolve into a sun-like star.^[4] The flare lasted 3 hours and 20 minutes.^[5] It significantly impacted the previously-thought timeline for when such events occur in the evolution of a protostar. Furthermore, it has improved astronomers' understanding of the Sun's earlier evolutionary stages.