Our Sun is doomed to eventually die after it has “lived” brilliantly and beautifully for about 10 billion years. The good news is that, because our Sun currently is a bit less than 5 billion years of age, it can still go on blissfully burning its supply of life-sustaining nuclear-fusing hydrogen fuel for another 5 billion years before the Grim Reaper comes to call. Solitary stars of our Sun’s mass all perish the same way–first ballooning in size to become enormous, swollen, crimson red giant stars before tossing their outer shimmering rainbow of multicolored gaseous layers into interstellar space–leaving behind only a dense Earth-sized relic core termed a white dwarf star to bear witness to the tragedy. In July 2019, an international team of astronomers announced that they had observed a rare dynamic event for the first time, when they witnessed the death of a distant red giant star. This observation provides a sneak preview of our Sun’s inevitable and sad demise.
Dr. Meredith Joyce, an astronomer based at The Australian National University (ANU) co-led the study with Dr. Laszlo Molnar and Dr. Laszlo Kiss from the Konkoly Observatory of the Hungarian Academy of Sciences. Dr. Joyce noted in a July 26, 2019 ANU Press Release that the star observed, dubbed T Ursae Minoris (T UMi), was similar to our Sun.
“This has been one of the rare opportunities when the signs of ageing could be directly observed in a star over human timescales. We anticipate our Sun and TMi will end their lives much more quietly and slowly compared with a supernova–a powerful and luminous explosion,” Dr. Joyce continued to explain.
The new findings strengthen the prediction that our dying Sun will become a red giant, before evolving into an expanding and glowing ring-shaped shell of gas in five billion years, leaving behind only a small white dwarf stellar corpse.
“It will become much bigger as it approaches death–eating Venus, Mercury and possibly the Earth in the process–before shrinking to become a white dwarf,” Dr. Joyce added.
The Life-Cycle Of Lonely Stars Like Our Sun
Stars are a lot like people. They are born, and then go on to enjoy a playful childhood and active youth–but, eventually, stars calm down when they evolve into glaring adults. However, the inevitable occurs when a star grows old and dies. Stars that are more massive than our Sun end their stellar lives when they explode in brilliant, violent supernova blasts. After the catastrophe, the erstwhile massive star leaves behind a dense, city-sized object termed a neutron star. Neutron stars are so dense that a teaspoon full of neutron star material can weigh as much as a herd of zebra. However, the most massive stars in the Universe have a different fate. When these especially massive stars run out of their necessary supply of life-sustaining nuclear-fusing fuel, they collapse into the oblivion of a black hole of stellar mass. 바카라사이트
Less massive stars, like our Sun, come to the end of the stellar road more peacefully, without the brilliant grand finale fireworks display of their more massive stellar counterparts. When stars like our Sun live alone, without a binary companion, they first evolve into red giants that ultimately blow off their outer layers to become white dwarfs encircled by a beautiful shell of multicolored gases.
All stars, regardless of their mass, are kept brilliantly bouncy as a result of an enduring battle between gravity and radiation pressure. Gravity tries to pull all of the star’s material in, while radiation pressure tries to push everything out. This delicate balance between the two eternal foes goes on from stellar-birth to stellar-death. In the end, when the old star runs out of its necessary supply of nuclear-fusing fuel, it can no longer churn out radiation pressure to counteract the relentless and merciless pull of its own gravity As a result, gravity wins the war, and the star is doomed.
Today, our Sun is a lonely star, but it was probably not born that way. Our Star probably formed as a member of a heavily populated open cluster, along with thousands of other newborn, fiery sibling stars. Our Sun was either gravitationally evicted from its natal cluster due to interactions with others of its fiery kind or it simply peacefully floated away into the space between stars approximately 4.5 billion years ago. Likewise, our Sun’s long-lost siblings are thought to have migrated to more remote regions of our Milky Way Galaxy, never to return.
Our entire Solar System emerged from the tattered remains left over from the nuclear-fusing ovens of previous generations of dead ancient stars. Our Sun–like others of its kind–was born within a dense, cold blob tucked tenderly within the whirling, swirling, ruffling folds of a churning dark, giant molecular cloud. The dense blob ultimately collapsed under the intense pull of its own gravity, thus giving birth to a hot, glaring baby star (protostar). Within the secretive depths of these enormous and beautiful clouds, that float like lovely, eerie phantoms throughout our Galaxy in huge numbers, fragile threads of material tangle themselves up together, and the resulting clumps grow ever larger and larger for hundreds of thousands of years. Then, pulled inward by the relentless crush of gravity, the hydrogen atoms existing within the clumps rapidly and dramatically fuse. This process of nuclear fusion triggers a violent conflagration that will rage with brilliant fury for as long as the new star lives–for that is how a star is born.