Hundreds of Massive Stars Have Simply Disappeared
The lifecycle of a star is regularly articulated as formation taking place inside vast clouds of gas and dust and then ending either as a planetary nebula or supernova explosion. In the last 70 years however, there seems to be a number of massive stars that are just disappearing! According to stellar evolution models, they should be exploding as supernova but instead, they just seem to vanish. A team of researchers have studied the behaviour of star VFTS 243 – a main sequence star with a black hole companion – and now believe it, like the others, have just collapsed, imploding into a black hole!
During the life of a star, the inward pulling force of gravity is balanced by the outward pushing thermonuclear force (the result of fusion in the core.) Once the core is rich in iron, as happens with massive stars about 8 times more massive than the Sun, the fusion process ceases as does the thermonuclear force. With the cessation of the force, the core collapses, the outer layers collapse in on the core and bounce back out as a massive explosion known as a supernova. The actual mechanism of the explosion and the formation of the compact object that is left behind from the core is still the subject of a lot of debate.
The supernova process is one of the most powerful explosions in the universe. As the star collapses, a shockwave is produced that can create fusion in the outer shell of the progenitor star. The reactions can create new elements heavier than iron. In a paper recently published by an international team of astronomers led by Alejandro Vigna-Gómez from the Max Planck Institute for Astrophysics in Germany the team shed new light on the process. They showed that it is possible for a star to be so massive that its gargantuan force of gravity can be strong enough that even the supernova explosion is not able to take place.
The team’s discovery seems to be linked to the concept of disappearing stars. Over the last few years, it has become evident that some stars seem to just vanish from view, neither passing through the planetary nebula phase nor going supernova. The discovery of supermassive stars undergoing complete collapse without supernova now provides a good explanation for the phenomenon.
The team reached their conclusion when they explored an object known as VFTS 243; a binary system which includes a star thought to be 25 times more massive than the Sun and a blackhole 10 times more massive than the Sun. Both objects orbit a common centre of gravity over a period of 10.4 days and lie in the Tarantula Nebula in the Large Magellanic Cloud – 160,000 light years away. The binary system is not the first of its kind to be discovered, such systems have been known about for decades.
Studying the system revealed the orbit was almost circular. Given that one of the stars had collapsed into a black hole, the nearly circular orbit and the lack of any evidence of an explosion all point to a star that collapsed completely. The complete collapse meant that all matter from the star collapsed into the blackhole and no material escaped out as a supernova. Could it be then that the team have finally revealed the mechanism by which massive stars have been vanishing? It certainly looks like it but further observations of binary systems with stars and black holes is required to confirm.
Source : Constraints on Neutrino Natal Kicks from Black-Hole Binary VFTS 243
The post Hundreds of Massive Stars Have Simply Disappeared appeared first on Universe Today.
Source: https://www.universetoday.com/167171/hundreds-of-massive-stars-have-simply-disappeared/
Anyone can join.
Anyone can contribute.
Anyone can become informed about their world.
"United We Stand" Click Here To Create Your Personal Citizen Journalist Account Today, Be Sure To Invite Your Friends.
Before It’s News® is a community of individuals who report on what’s going on around them, from all around the world. Anyone can join. Anyone can contribute. Anyone can become informed about their world. "United We Stand" Click Here To Create Your Personal Citizen Journalist Account Today, Be Sure To Invite Your Friends.
LION'S MANE PRODUCT
Try Our Lion’s Mane WHOLE MIND Nootropic Blend 60 Capsules
Mushrooms are having a moment. One fabulous fungus in particular, lion’s mane, may help improve memory, depression and anxiety symptoms. They are also an excellent source of nutrients that show promise as a therapy for dementia, and other neurodegenerative diseases. If you’re living with anxiety or depression, you may be curious about all the therapy options out there — including the natural ones.Our Lion’s Mane WHOLE MIND Nootropic Blend has been formulated to utilize the potency of Lion’s mane but also include the benefits of four other Highly Beneficial Mushrooms. Synergistically, they work together to Build your health through improving cognitive function and immunity regardless of your age. Our Nootropic not only improves your Cognitive Function and Activates your Immune System, but it benefits growth of Essential Gut Flora, further enhancing your Vitality.
Our Formula includes: Lion’s Mane Mushrooms which Increase Brain Power through nerve growth, lessen anxiety, reduce depression, and improve concentration. Its an excellent adaptogen, promotes sleep and improves immunity. Shiitake Mushrooms which Fight cancer cells and infectious disease, boost the immune system, promotes brain function, and serves as a source of B vitamins. Maitake Mushrooms which regulate blood sugar levels of diabetics, reduce hypertension and boosts the immune system. Reishi Mushrooms which Fight inflammation, liver disease, fatigue, tumor growth and cancer. They Improve skin disorders and soothes digestive problems, stomach ulcers and leaky gut syndrome. Chaga Mushrooms which have anti-aging effects, boost immune function, improve stamina and athletic performance, even act as a natural aphrodisiac, fighting diabetes and improving liver function. Try Our Lion’s Mane WHOLE MIND Nootropic Blend 60 Capsules Today. Be 100% Satisfied or Receive a Full Money Back Guarantee. Order Yours Today by Following This Link.
