The Chilean ALMA telescope has just detected an “intruder” within a protoplanetary disk.
The constellation Canis Major is perhaps less known to the general public than its neighbor the Big Dipper, but it is nevertheless the target of many amateur astronomers. Indeed, it contains within it the star Sirius, which is none other than the brightest point in the night sky (among the stars, the Moon is an exception).
But while amateurs put their telescopes in the direction of this star, professional astronomers gaze slightly aside in a binary system to say the least intriguing. The first point of interest of Z Canis Majoris (Z CMa) is that the system is only 300,000 old, so it’s a universe-wide baby a few days old.
“It’s as sudden as lightning”
But other very interesting news concerning this system, the scientists believe to have found an intruder there. Far from being a part of “Where’s Charlie”, star system intruders like this are actually quite common in computer simulations, but we had never really seen one before.
Rubong Duong, professor at the University of Victoria in Canada and principal investigator in this study, explains that their discovery amounts to “Photograph the lightning striking a tree. ” As the study explains, “intruders” are generally smaller stars that arise not far from a system.
A passage that leaves traces
The latter will then come closer because of the gravity of the most massive star, and projections of their disc can cross the protoplanetary discs of other stars causing jets of gas and matter in a chaotic pattern. Scientists are now wondering about the long-term impact of the passage of this intruder.
The latter has indeed greatly changed the face of the protoplanetary disc around the star, and its evolution for the next millions of years was changed in an instant. The objective is now to increase the number of observations of protoplanetary systems in order to be able to capture the traces left by the passage of other intruders.