The jet observed by the Atacama Large Millimeter/submillimeter Array (ALMA) is ejecting material away from MWC 349A at a blistering 500 km per second (311 miles per second) and is likely launched by a magnetohydrodynamic wind — a type of wind whose movement is dictated by the interplay between the star’s magnetic field and gases present in its surrounding disk.
Artist’s concept shows MWC 349A with its surrounding dust and gas, which are being formed by winds and the high-speed jet. Image credit: ALMA / ESO / NAOJ / NRAO / M. Weiss, NRAO, AUI & NSF.
MWC 349A, a huge star located 3,900 light years from Earth in Cygnus constellation is known as MWC349A.
The star is also known by the name SDSS J203245.51+403936.6. It has a total mass of 30 solarmass.
MWC 349A, one of the most visible radio sources in space, is also one of a few objects that has hydrogen masers.
The masers amplify microwave radio waves, which makes it possible to examine processes often too small for us to observe.
This unique feature allowed Sirina Prasad, from Harvard & Smithsonian Center for Astrophysics, and her colleagues to map MWC349A’s disc in detail for their first attempt.
Prasad stated, “A mazer is like an naturally occurring laser.”
It’s an outer-space area that emits bright light.
We can now see the light, trace its origin and get one step closer towards understanding what is really happening.
Researchers were able use the masers in order to discover previously unknown structures within MWC 349A’s immediate surroundings.
“We used masers made from hydrogen to probe the dynamic and physical structures within the gas around MWC349A. We found a flattened disk of gas with a diameter 50 AU. This is approximately equal to the Solar System’s size,” stated Dr. Qizhou Zhang of Harvard & Smithsonian Center for Astrophysics.
We also discovered a jet component that was fast moving within the wind flowing away from our star.
At a staggering 500km per second, the observed jet is pushing material from the star.
Researchers believe that the magnetic force is responsible for launching a jet so fast.
MWC 349A could represent a magnetohydrodynamic force, which is a kind of wind that’s controlled by the interaction between its magnetic field and the gases in the surrounding disk.
Prasad stated that MWC 349A had been previously understood to mean the star was enclosed by a rotating disc and photo-evaporating winds.
This system does not have strong evidence of an additional collimated plane.
Although we do not know the source of the jet or its production process, the possibility exists that the magnetohydrodynamic winds are responsible. In this case, the magnetic field would be responsible for the launch of rotating material out the system.
This could allow us to understand MWC 349A’s disk-wind dynamics and how they interact with circumstellar jets and winds in star systems.
Researchers will be presenting their findings at this week’s The 241st Meeting of the American Astronomical Society (AAS 241) Seattle, Washington
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S. Prasad The authors and others. 2023. ALMA is used to spatially resolve Hydrogen Recombination Line Maser Emissions from MWC349A. AAS 241Program number: 474.04