According to a July 20 release from the Atacama Large Millimeter/ submillimeter Array, or ALMA, astronomers have acquired a brilliant close-up of a stream of material floating away from a newborn star. The vibrant glow from the celestial body comes from carbon monoxide molecules. The new images revealed to astronomers that the jets emanating from the object are even more energetic than was previously believed.
As newborn or otherwise young stars eject materials at extremely high speeds, when the material collides with the surrounding gas, it glows and creates a Herbig-Haro object. Herbig-Haro 46/47, situated 1400 light-years from Earth in the Vela constellation, became the object of study using ALMA while the telescope was still far from completion.
The recently captured images show fine detail in two jets, with one pointing towards Earth and one moving away from it. This latter jet was nearly invisible in earlier images made in visible light, due to blurring from the dust clouds that surround the newborn star. In addition to providing sharper images, ALMA has also enabled astronomers to calculate the speed at which the glowing material is moving through space.
Following the analysis of the observations of Herbig-Haro 46/47, astronomers discovered that a portion of the ejected material had much higher speeds than had been calculated before, meaning that the gas jets have much more energy and momentum than was previously believed.
According to team leader and lead author of the study which describes the observation, Héctor Arce of Yale University said, “ALMA’s exquisite sensitivity allows the detection of previously unseen features in this source, like this very fast outflow. It also seems to be a textbook example of a simple model where the molecular outflow is generated by a wide-angle wind from the young star.”
According to study co-author Stuartt Corder of the Joint ALMA Observatory in Chile, “The detail in the Herbig-Haro 46/47 images is stunning. Perhaps more stunning is the fact that, for these types of observations, we really are still in the early days. In the future ALMA will provide even better images than this in a fraction of the time.”
An additional co-author, Diego Mardones of the Universidad de Chile, emphasized, “[T]his system is similar to most isolated low mass stars during their formation and birth. But it is also unusual because the outflow impacts the cloud directly on one side of the young star and escapes out of the cloud on the other. This makes it an excellent system for studying the impact of the stellar winds on the parent cloud from which the young star is formed.”