The massive star MWC 349A is one of the brightest radio sources in the sky. But, at 3,900 light-years away from Earth, scientists needed help to see what’s really going on, and in this case, to discover a jet of material blasting out from the star’s gas disk at 500 km/s. Previously hidden amongst the winds flowing out from the star, the jet was discovered using the combined resolving power of ALMA’s Band 6 (right) and Band 7 (left), and hydrogen masers— naturally occurring lasers that amplify microwave radio emissions, shown here in this ALMA science image. The revelation may help scientists to better understand the nature and evolution of massive stars.
Credit: ALMA (ESO/NAOJ/NRAO), S. Prasad/CfA