Thanos was born approximately 1,000 years ago on the planet Titan to A'Lars, along with his brother Eros. Thanos deems the growth of Titan's population to be unsustainable, so he proposes to arbitrarily kill half of Titan's population.
Russo claims Thanos is around 1,000 years old, calling him to be "the Genghis Khan of the universe." The filmmakers could have chosen any reasonable age for the villain, but having Thanos be around 1,000 years old respects the larger canon of the comics, which, while vague, keeps him around this age.
Directors Joe and Anthony Russo and writers Christopher Markus and Stephen McFeely provide the commentary, and they revealed that Thanos chose to wait because he had no idea about the location of the Soul Stone (via io9).
Is Thor older than Thanos? Thor (about 1500 years old) in the MCU is a skilled Warrior who is apparently older than Thanos (about 1,000 years old).
Yes, as an Eternal, Thanos is immortal by human standards. Immortal meaning can not die by disease, or old age, as in natural causes. Thanos is NOT immortal but extremely long lived (much like Asgardians, he does age).
Thanos' origin Thanos was born on Titan, one of Saturn's moons. He is not a Titan, like the beings from Greek mythology, but the confusion may stem from his birthplace. Thanos is actually an Eternal, the son of A'lars and Sui-San. The Eternals are a fictional race from the Marvel universe.
Advanced Longevity: It has been confirmed that Thanos is an extremely long-lived being and was roughly over 1000 years of age by the events of the Infinity Wars and the Battle of Earth. Even during the 2010s, he had displayed no signs of aging or any decline in his physical powers.
In the aftermath of his failure, Thor had a new-found determination to kill Thanos and undo the Snap. The remaining Avengers converged on the Titan's home to find him wounded and the Infinity Stones destroyed. Seeking vengeance, Thor raised Stormbreaker and, with one fell swoop, beheaded Thanos.
He simply wanted him dead at all costs because he was his biggest threat. As per the user, the director of Avengers confirmed that Thanos was most scared of Iron Man.
After escaping to the Garden and destroying the Stones, he is eventually killed by Thor. Five years later, an alternate version of Thanos from 2014 time travels to 2023 to battle the Avengers once again, but is killed by Tony Stark.
No, he doesn't. He doesn't fear Odin to the point even a spear-wielding All-Father respects him as an adversary worth saluting, considering him as a foe he's never fought in eons.
Thanos didn't lift Mjolnir, Captain America did
With Mjolnir's worthiness enchantment resulted in Thor being able to lift the hammer only if he is considered to be worthy, but likewise, the enchantment is not discriminatory in nature, and anyone who is deemed worthy is able to lift the hammer.
Thor is Immortal, Not Invincible
In Avengers: Infinity War, Thor revealed that he was over 1500 years old. It's clear that age doesn't affect him the way it does normal mortals, as with most immortals, he is aging at a slower rate. While Thor will eventually die, it will take thousands of years for it to happen.
Meanwhile, Groot was around four years old during the events of the Avengers: Infinity War and Endgame. Then, in The Holiday Special and Vol. 3, he is around five to six years old. If you count the time he was snapped as lifespan, in that case, he is around 11 years old in Guardians of the Galaxy Vol.
Thor. While Steve Rogers gets the title of the oldest human avenger, Thor Odinson, as the mighty Asgardian God of Thunder, has a much longer life span than any of his Earth-born friends.
1936 The Phantom
Created by Lee Falk (USA), the first superhero was The Phantom, who debuted in his own newspaper comic strip on 17 Feb 1936. It recounted the adventures of Kit Walker, who donned a mask and purple outfit to become The Phantom – aka “the ghost who walks”.
Galactus is billions of years old and is older than the concept of time and space in our Universe. Now since Galactus came from the sixth Incarnation of the Universe, it's only logical that he is older than the current time, current space, current gravity, and the current Universe as a whole.
Captain Marvel is long-lived, but she is not immortal
She is simply extremely long-lived. Her alien physiology slows down the decay of her cells and prevents her from aging in a manner similar to a full-blooded human being.
Superhuman Longevity: Like all Asgardians, Odin was extremely long-lived, as he ages far slower than normal humans. During the last Great War between Asgard and Jotunheim, Odin was at least 18,000 years old, when he died, he was over 5,000 years old, if not older.
Thanos is a mutant member of the race of superhumans known as the Titanian Eternals. The character possesses abilities common to the Eternals, but amplified to a higher degree through a combination of his mutant–Eternal heritage, bionic amplification, mysticism, and power bestowed by the abstract entity, Death.
As Thanos grew older, Death became his confidante and the only person that knew of his secret activities that consisted of vivisecting animals. By this time, Thanos had fallen in love with the girl, but she rejected his advances.
That villain is, of course, Kang the Conqueror, who's set to be the Avengers' next opponent in the upcoming Avengers: The Kang Dynasty. And while Thanos is certainly a hard act to follow, Kang may be a far greater threat than the Mad Titan ever was.