Grace having a longer life span on erid than he would have on earth
I’m THINKING okay gimme a second (hey @rocket-amongst-the-stars you said to tag you in my hcs so here’s one) and no I don’t care if it doesn’t “make sense in canon” it’s FUN okay I want grace to live as long as Rocky, sue me
Because so many eridians are putting in so much work to keeping grace alive, they actually end up lengthening his life span by a LOT compared to what it would have been on earth.
Firstly- nutrition. Between the meburgers and the synthesis of any other nutrients his body could need, he’s kept incredibly healthy, far beyond what could ever be realistically achieved on earth
Next- exercise and healthcare. The Hail Mary is equipped with an automated medical system in the form of Armando which can not only diagnose and heal almost any wounds, but is also able to use electrodes to stimulate his muscles. On top of that, there’s plenty of space in his enclosure (yeah I’m calling it an enclosure, he is in an eridian zoo now idc) for him to get proper exercise in, and you KNOW Rocky would be more than happy to skitter along with him while he runs, plus once they get the ocean temperatures right, he’ll start dedicating at least an hour a day to swimming (Rocky can’t swim, but Adrian is very tall and can walk along to sea floor with rocky perched on his head to chatter at grace while he swims). On top of all of that, there is an entire planet of incredibly intelligent beings ready to thrum at a moments notice if anything goes wrong with grace’s health, which leads to armando being almost constantly improved, and there’s a near-infinite supply of xenonite ready to be formed into the best possible version of any accessibility aid that could ever be needed for him.
Third- the matter of gravity. Technically, the intense pressure of gravity on erid should really cause increased bone decay, faster development of arthritis etc, but the thing is- grace lives in his enclosure (also I like the idea of him, Rocky and Adrian going out into space to help save other solar systems, but same shit; everything in both the ships and his enclosure can be adjusted to meet his needs) When his bones and joints do start to wear down, they simply reduce the gravity in his enclosure ever so slightly to reduce the pressure on them, allowing him to remain much more active for much longer than any normal human, which combined with the advanced medical care and access to insanely strong and well developed options for things such as hip replacement surgery or pacemakers, will keep him “healthy” in a way that eventually leads to him feeling a bit like a cyborg with the amount of metal inside him and wrapped around him in the form of advanced prosthetics.
Fourth- this is a bit of a rogue one, but he can almost “skip time” to allow for more developments to be made back on Erid for the purpose of keeping him as healthy and comfortable as possible, simply by going out on expeditions to save other stars because of the time dilation. He and his crew go away for a few years and return to erid 15-30 years later after the remaining eridians have had time to thrum on different ways to prolong his measly human life span.
As it is, Grace actually ends up outliving Adrian. It’s awful, but after all of the years that Rocky was in space and the dilated time experienced back on erid, Adrian was always going to die before Rocky, and at least now Rocky is able to lean on Grace through the grieving process. It was a surprise to everyone, eridian and human alike, however, that Grace outlived Adrian; he never forgot the large role Adrian played in expanding his lifespan. Unfortunately, once Grace also passes on, Rocky is left alone, with only his and Adrian’s pebbles to support him. His children do all they can, but after grace’s passing, it doesn’t take long, a mere twenty years, until Rocky joins him and his spouse up in the stratosphere. The remaining time he has left, though, is at least filled with the comfort that wherever Adrian is, he has Grace to hold onto until Rocky is able to meet them there, just like Rocky was able to hold onto Grace after Adrian’s passing.
Before Grace’s passing, he and the eridians work together to create another probe to send to earth; of course, everyone he ever knew back on earth has been dead for many, many years; even his young students will have died of old age almost a century before him. But that probe is filled with every piece of knowledge the eridians and Grace had learned, from the existence of other solar systems and life forms to ways to increase the human life span to centuries rather than decades. He hopes it helps them, in some ways, but even if that probe never reaches earth, he dies knowing that he and his friends made more of a difference than he could have ever expected for hundreds of different life forms.
