Astronomers have discovered a red giant star in the last stages of its life emitting strange smoke-like rings for the first time.
The team observed six slowly expanding rings and hourglass-shaped structures resulting from the high-speed ejection of material into space.
The star, called V Hydrae, is located about 1,300 light-years from Earth and is the so-called asymptotic giant star (AGB) rich in carbon. It is a star that has reached the final stage of its existence, a red giant, before collapsing into a white dwarf. Observing the behavior of such stars thus helps astronomers understand what happens in the final stages of the stellar death process.
And astronomers knew before that stars at this stage sweep material from their core and expel it into the surrounding space.
This ejection of material was what a team of scientists from NASA’s Jet Propulsion Laboratory in California and the University of California, Los Angeles observed when they looked at the V Hydrae using ALMA, or the Large Millimeter/Sub-Atacama Array (ALMA), and the Hubble telescope. space alien.
And they discovered that the star ejects six disks and two structures of matter in the form of an hourglass from inside it, and it is known at this point to fuse helium with carbon.
During their normal life, stars fuse hydrogen into helium. The moment the hydrogen runs out marks the beginning of the red giant phase, which eventually sees the star burning helium and producing carbon.
In the asymptotic giant star phase, the stars gradually pass through helium reserves as well, and this appears to be happening for the V Hydrae.
“Our study significantly confirms the traditional model for how asymptotic-giant stars die—by expelling mass fuels through relatively slow and steady globular winds over 100 years,” lead author Ragvendra Sahai, an astronomer at NASA’s Jet Propulsion Laboratory in California, explained in a statement. A thousand years or more is, at best, incomplete, or at worst, incorrect.”
The astronomers were particularly surprised that the V Hydrae was spewing out “rings of smoke” (rings of dust) rather than just the gaseous atmosphere, co-author and astronomer Mark Morris of UCLA said in the same statement.
This finding will be significant, given that more than 90% of stars with the mass of the Sun (or larger) eventually become AGB stars, because they lose the ability to generate energy through nuclear fusion.
Morris continued: “The end state of stellar evolution – when stars undergo the transition from being red giants to becoming white dwarf stellar remnants – is a complex process that is poorly understood. The discovery that this process could involve releasing rings of gas, in conjunction with the production of high-pitched jets The speed and choppy material, brings a new and wonderful wrinkle to our exploration of how stars die.”
The two hourglass-like clouds and an additional “jet-like structure” were moving away from the star at half a million miles per hour (240 km per second).
And hourglass-like clouds aren’t entirely new to science, as astronomers have discovered such phenomena before in stars dropping the atmosphere, such as inside the Southern Crab Nebula.
It is known that the V Hydrae emits bursts of very hot gases, or plasma, about every 8.5 years, and scientists believe that some of its strange behavior may be related to a companion star, however, its existence has not been confirmed.
“V Hydrae has impressed us with its multiple rings and actions, and because our Sun may one day face a similar fate, it has caught our attention,” Sahai said.
Source: myspace