ALMA Observations of the Extraordinary Carina Pillars.

Astronomers have looked inside the Carina Nebula to learn more about the processes within its pillars. Nebulae where stars form are very busy places. But clouds of gas and dust often prevent astronomers from seeing what’s going on up there. Scientists have now used the Atacama Large Millimeter Array (ALMA) to peer inside the pillars of the Carina Nebula. They studied the molecular streams that these objects emitted in the famous “stellar” cradles.

Therefore, scientists have examined many circumstantial disks around forming stars. They were also able to measure the range of the molecular jets involved. Astronomers concluded that the origin of these jets are low- or medium-mass protostars. When young stars form, falling material is heated and ejected into a stream along the protostar’s rotation axis. As a result, the jets “crash” into the gas and dust of the stellar “nursery”. The collisions excite the gases in the nebula and cause them to glow. The planes themselves move very fast, up to hundreds of thousands of kilometers per hour. Astronomers call the clouds of excited gas and dust associated with protostellar objects Herbig-Haro. These are bright nebulae within larger nebulae. They exist thanks to newborn stars. They are named after George Herbig and Guillermo Haro, who were the first to study them in detail. Essentially, they are part of the star birth process.

In the ALMA data, scientists discovered several sources emitting millimeter-wave radiation. These are the Herbig-Haro objects: HH 666, HH 1004, HH 1006, HH 1010 and HH 1066. They also detected significant carbon monoxide emissions associated with them. They appear curved and create large shock waves as they crash into the surrounding nebula, creating voids. Scientists estimate that photoevaporation will destroy the pillars in just 100,000 to 1,000,000 years. Once gone, the circumstellar disks around newly formed stars will be exposed to radiation from the Trumpler cluster. Most likely, they will transform into protoplanetary disks (like those observed in the Orion Nebula) within a fairly short period of time.

HH 666 is the most famous Herbig-Haro object in the Carina Nebula. It has been observed in visible and infrared light, as well as in millimeter waves. The object contains a protostar – the source of the jet. Scientists estimate it extends at least 10 light-years from the source.

source: https://arxiv.org/abs/2310.10801