Astronomers spot bow shocks from jets of baby star
Astronomers have observed a series of ring-like structures formed by the jet of a newborn star. The observations confirm theoretical models.
An international team of astronomers have captured the most detailed images of a jet launched by a young star, revealing a series of delicate ring-like structures that record decades of violent outbursts during the earliest stages of the star's life. The bow shocks confirm theoretical models three decades old, but has not been directly observed before. The astronomers focused on a binary system designated as SVS 13 at a distance of about 1,000 lightyears from the Earth. The high-resolution images reveal hundreds of nested molecular rings, each traced to an energetic burst during the infancy of the star.
The bow shocks allowed the astronomers to reconstruct the chronological record of the earliest stages of the star's life. Embryonic stars feed on infalling dust and gas, that flattens into an accretion disk because of slight initial movement. The magnetic fields of the disk causes some of the material falling in to be pushed away at tremendous velocities by polar jets. The bow shocks can be reliably dated, allowing the astronomers to reconstruct a timeline of the past of the star. The observations also improve the scientific understanding of how young stars grow, and how planetary systems are assembled from the material leftover from the birth of a star.
The earliest stages of the life of a star
The researchers were able to identify over 400 rings from SVS13, that reveal how its shape and speed changed over time as it punched through the surrounding environment. The researchers were able to reconstruct a 3D structure of the jet in unprecedented detail. The youngest ring matches a bright outburst observed from the star in the early 1990s. Stars are born from dense clouds of gas and dust. In the early stages, they undergo energetic outbursts that heat up and disturb the surrounding material. The tightly collimated jets of gas play a crucial role in regulating the infalling material, and how rapidly the star can accrete matter. The observations were made by the Atacama Large Millimetre Array (ALMA), located in the deserts of Northern Chile. A paper describing the findings has been published in Nature Astronomy.