HOPS 383 is a Class 0
protostar
A protostar is a very young star that is still gathering mass from its parent molecular cloud. The protostellar phase is the earliest one in the process of stellar evolution. For a low-mass star (i.e. that of the Sun or lower), it lasts about 50 ...
. It is the first class-0 protostar discovered to have had an outburst,
and as of 2020, the youngest protostar known to have had an outburst.
[ The outburst, discovered by the Herschel Orion Protostar Survey (HOPS) team, was first reported in February 2015 in '']The Astrophysical Journal Letters
''The Astrophysical Journal'', often abbreviated ''ApJ'' (pronounced "ap jay") in references and speech, is a Peer review, peer-reviewed scientific journal of astrophysics and astronomy, established in 1895 by American astronomers George Ellery H ...
''.
Observations
Outburst
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. After 6 years, observations showed no signs of fading.[
]
X-Ray
The Chandra X-Ray Observatory
The Chandra X-ray Observatory (CXO), previously known as the Advanced X-ray Astrophysics Facility (AXAF), is a Flagship-class space telescope launched aboard the during STS-93 by NASA on July 23, 1999. Chandra is sensitive to X-ray sources ...
detected an X-ray flare from HOPS 383 in December of 2017. This was the first detection of X-rays from a Class 0 protostar that will evolve into a sun-like star. The flare lasted 3 hours and 20 minutes. 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.
References
{{Stars of Orion
Orion (constellation)
Protostars