Throughout his over-80-year history, the mortality of Superman has often come into question. While the Man of Steel might be faster than a speeding bullet, more powerful than a locomotive and able to leap tall buildings in a single bound, one of Superman's most impressive powers is his apparent ability to live forever.

Although he was killed at the hands of Doomsday in Death of Superman, he was still resurrected through both scientific and supernatural means just a few months later. Barring some sort of outside force, it seems like its nigh-impossible for the Last Son of Krypton to die of old age from everything we've seen around the DC Universe.

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While there have been multiple examples of Superman’s longevity, the most recent confirmation of Superman’s immortality came in the short story, "Of Tomorrow," Tom King, Clay Mann, and Jordie Bellaire’s entry in 2018’s Action Comics #1000. In this story, Superman is seen nearly five billion years in the future, saying goodbye to the graves of his adopted parents right before the Dun evolves into a red giant and destroys the Earth.

But "Of Tomorrow" is hardly the only story to introduce the concept of a Superman who cannot die. One of the more famous instances of this version of the character is Superman Prime—the golden Superman who appeared in the DC One Million crossover by Grant Morrison, Val Semeiks, and Prentis Rollins. This Superman hailed from the 853rd Century and contained nearly godlike levels of power. Having outlived everyone he ever cared about -- his parents, his teammates, and even his beloved Lois -- this Superman passed on his mantle to a successor in the late 21st Century and traveled the cosmos until somewhere in the 700th, where he returned to Earth's solar system and spent 15,000 years living in the heart of the Sun.

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DC Comics' All-Star Superman flies too close to the sun.

This idea of Superman going to live within the Sun appears again in Morrison’s work, even serving as the climax for his, Frank Quitely and Jamie Grant's All-Star Superman series. The entire premise of the story centers around Superman’s final days, but instead of meeting his maker, the Big Blue Boy Scout flies into the heart of the Sun, repairing the damage done by the villain Solaris, and seemingly staying there to achieve his ultimate form as Superman Prime. Even when diagnosed with a terminal condition, Superman withstood death.

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All-Star Superman is far from the only alternate reality tale that toys with Superman’s mortality. Kingdom Come by Mark Waid and Alex Ross featured a Superman who actually grew more powerful as he aged, and the spiritual sequel, "Thy Kingdom Come," from Justice Society of America by Geoff Johns, Dale Eaglesham, Alex Ross, and more, showed this version of Superman to still be alive in the 31st Century watching his descendants as they fly with the Legion of Superheroes.

Kingdom Come Old Superman by Alex Ross

There have been other instances of a Superman that doesn’t age, or at least ages incredibly slowly, within stories like Infinite Crisis, again by Geoff Johns, joined by Phil Jimenez, Jerry Ordway, and more. Likewise, the isolation that will be caused by Clark’s power and longevity is addressed in Scott Snyder, Jim Lee, and Dustin Nguyen’s Superman Unchained, as well. But one consistency within all of these stories is the fact that Superman never stops protecting others and doing what he believes is right. His legacy spreads throughout the universe, inspiring heroes from distant stars, far-flung futures, and even his close friends, and he is one of the few beings who will live to see its impact on all times.

While the loss of his loved ones may cause his disillusionment in stories like DC One Million or Kingdom Come, the Man of Steel always returns as a symbol of the hope that he wears on his chest. As long as Superman lives, there will always be someone who will to stand up for truth and justice throughout the DC Universe. The battle against evil is a never-ending one, and it needs a never-ending hero to fight it.

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