National Optical Astronomy Observatory Press Release: Punching Above Its Weight, a Brown Dwarf Launches a Parsec-Scale Jet
https://www.noao.edu/news/2017/pr1701.php
Astronomers using the SOAR telescope at the Cerro Tololo Inter-American Observatory report the discovery of a spectacular extended jet
from a young brown dwarf. With masses too low to sustain hydrogen fusion in their interiors, brown dwarfs occupy the mass range between
stars and giant planets. While young stars are commonly found to launch jets that extend over a light year or more, this is the first
jet with a similar extent detected from a brown dwarf. The result lends new insight into how substellar objects form.
Intrinsically faint, brown dwarfs have been more elusive and difficult to study than stars. Although they are often portrayed as exotic
creatures as a result, brown dwarfs are actually far more numerous in our Galaxy than stars like the Sun. The discovery, accepted for
publication in the Astrophysical Journal, supports the emerging picture that brown dwarfs form similarly to stars.
The image shows the jet, HH 1165, launched by the brown dwarf Mayrit 1701117 in the outer periphery of the 3 million year old sigma Ori
cluster. Traced by emission from singly ionized sulfur, which appears green in the image, the jet extends 0.7 light years (equivalent to
0.2 parsecs) northwest of the brown dwarf. The emission knots along the jet reveal that the mass loss is time variable, probably a result
of episodic accretion onto the brown dwarf. The red nebulosity southeast of the brown dwarf is a reflection nebula that traces the outflow
cavity in the direction of the counterjet.
