The Detail That Changes Everything: Time
One of the most important things in any continuation of Project Hail Mary is that Graceâs journey cannot be treated like an ordinary trip.
Because of relativity, time does not pass the same way for everyone.
For Grace, the mission is lived in years.
For Earth, it becomes decades of fear, collapse, reconstruction, and waiting.
The distance between worlds is not only spatial.
Grace does not disappear for a short while.
He becomes a historical absence.
While he travels, Earth keeps living under the shadow of the Astrophage crisis. Agriculture fails. Nations reorganize. Governments make desperate decisions. Technology advances not because humanity is comfortable, but because survival demands it. The planet continues existing beneath a dying Sun, with no guarantee that anyone will ever come back with an answer.
And then, years later, Earth receives the package sent by the Hail Mary.
But that package is not only a biological solution to the Astrophage problem.
From what the film shows, Grace sends everything together:
the information needed to save the Sun;
the information about Erid;
and the proof that another intelligent civilization exists.
So humanity does not receive only a cure.
It receives a historical rupture.
Earth discovers, all at once, that the Sun can be saved, that Grace encountered another intelligent species, that this species was also fighting for survival, and that humanityâs salvation depended on cooperation between a human and an Eridian.
Humanity would not have time to process those two revelations separately. The cure and first contact would arrive as part of the same event.
It would be impossible to say:
âRocky was just a detail.â
Because Rocky is not a detail.
Rocky is part of the salvation.
Erid would not be just an astronomical curiosity. It would be the other world that almost died. The other civilization that faced the Astrophage. The other side of the story.
And Grace would not be remembered only as the man who saved Earth.
He would be remembered as the person who, almost accidentally, began humanityâs first era of interstellar contact.
Where the AU Actually Begins
The fictional part of this AU is not that Grace sends information about Rocky and Erid.
That already belongs to the logic of the film.
The AU begins after that.
It begins when Earth has to decide what to do with that revelation.
How do governments react?
Who tries to control the data?
Who gets access to information about Erid?
How do scientists try to understand Eridian biology without being able to simply visit Erid immediately?
How do religions, universities, militaries, space agencies, and ordinary people react to the fact that humanity was saved through cooperation with an alien species?
How does Rocky come to be seen on Earth?
How does Grace become a myth before any possible return?
how do two civilizations that nearly died learn to speak to each other after catastrophe?
That is the foundation of this AU.
It is not an instant utopia.
Earth survives, but it does not come out untouched.
Erid survives, but it carries its own trauma as well.
First contact is not born from peace, curiosity, and luxury. It is born from desperation. It is born because two stars were dying. It is born because two individuals, Grace and Rocky, chose to trust each other when everything suggested that trust should have been impossible.
Humanity After the Astrophage
In this idea, post-Astrophage humanity advances enormously.
Not because humans suddenly become morally better, but because they are forced to survive.
The crisis accelerates research in energy, closed agriculture, medicine, artificial intelligence, biotechnology, orbital systems, recycling, extreme habitats, and space propulsion.
Dangerously good at turning a scientific discovery into a struggle for power.
So Earth does not become a perfect federation just because it receives the Hail Mary data. On the contrary: first contact creates new conflicts.
Some people want cooperation.
Some treat Erid as an ally.
Others treat Erid as a threat.
Some see Rocky as a person.
Others try to reduce him to a symbol, a tool, a scientific proof, or a piece of historical property belonging to humanity.
And that is exactly where the continuation becomes interesting.
Because the question stops being only:
âHow do we save the Sun?â
âHow do we prevent humanity from turning its first alien friend into property?â
He knows that contact with Erid cannot become the possession of Earth, of a government, or of an institution. Rocky is not a resource. Erid is not a colony. The Eridians are not tools.
So one of the foundations of this AU is precisely the attempt to turn first contact into cooperation â not domination.
The Eridians remain Rockyâs species.
They live in conditions lethal to humans: extreme pressure, extreme temperature, an incompatible atmosphere, and a biochemistry that requires strict environmental separation.
They are not humans with a different appearance.
And that is what makes Grace and Rockyâs bond so powerful.
They should not be able to share a space.
They should not be able to talk.
They should not be able to trust each other.
In this AUâs continuation, the Eridians become indispensable in fields where they are far beyond humans: materials engineering, xenonite, high-resistance structures, pressurized environments, thermal control, acoustics, life support, and the construction of incompatible habitats.
At the same time, humans offer knowledge that the Eridians did not develop in the same way: advanced computation, biological modeling, molecular medicine, simulations, artificial intelligence, automation, and comparative translation.
Over time, Grace and Rockyâs friendship stops being only a personal story.
It becomes a scientific bridge between species.
Not a bridge without fear.
Not a bridge without conflict.
The First Great Change: Building a Place Where the Other Can Exist
One of the strongest ideas in this AU, to me, is that diplomacy does not begin with speeches.
It begins with life support.
A human cannot simply walk on Erid.
An Eridian cannot simply walk on Earth.
The atmosphere, pressure, temperature, and chemistry of each world are lethal to the other.
So before any beautiful embassy, before any treaty, before any ceremony, both civilizations would need to answer a brutally practical question:
how do we create a space where the other can breathe?
That makes habitat technology almost philosophical.
To build an environment for the other is to recognize that their body matters.
That their survival matters.
That they do not need to become similar to you in order to be welcomed.
And that, to me, is one of the most beautiful consequences of Grace and Rockyâs contact.
Human-Eridian cooperation would not be only an exchange of technology.
It would be the literal construction of places where two incompatible forms of life can exist without destroying each other.
Another field that would change immediately is medicine.
Grace living among the Eridians would force Erid to develop ways to keep a human organism alive in a world that should be absolutely incompatible with him.
That does not mean magical rejuvenation.
It does not mean the Eridians can solve everything.
They had never known humans before.
But they do have extreme precision engineering, extraordinary environmental control, resistant materials, acoustic sensors, delicate instruments, and an enormous ability to construct stable environments.
Grace, on the other hand, brings human knowledge with him: biology, genetics, physiology, Earth medicine, the Hail Mary data, and his own experience as an alien organism being kept alive on Erid.
From that, comparative medicine is born.
Grace does not become young again as if he drank a potion.
The idea is stronger if it stays more limited: his body is maintained, repaired, stabilized, and protected through Human-Eridian technology. He remains a man marked by lived time, but not destroyed by an environment that should have killed him.
And that feels much closer to the scientific spirit of Project Hail Mary.
Cooperation, error, testing, maintenance, and care.
Travel Is Still Difficult
Another point I wanted to preserve is that Astrophage does not erase relativity.
It makes interstellar travel possible, but it does not make the universe small.
Messages still take time.
Journeys still separate people.
Every mission can still mean years for the traveler and decades for those waiting.
So, at the beginning of this AU, humans and Eridians do not immediately become a comfortable interstellar civilization. Their relationship is slow, difficult, full of delays, archives, messages, probes, and incomplete interpretations.
A question asked by one civilization may take years to reach the other.
An answer may return after the person who asked has grown old, changed position, or died.
This creates a very specific culture:
researchers working for readers who may not even have been born by the time the message arrives.
First contact, in this context, is not a live conversation.
It is correspondence between worlds separated by time.
But it is also beautiful.
Because continuing to answer becomes an act of scientific faith.
Once humans and Eridians prove that a relationship between radically different species is possible, the universe of the AU does not need to stop with two civilizations.
But I also did not want the expansion to feel easy.
Each new civilization needs to bring a different question.
With the Eridians, the question is:
can we recognize a person in a body completely incompatible with ours?
With the Avelari, the question becomes:
can we accept that another species understands space, gravity, and distance better than we do?
With the Izerix, the question is harsher:
can we cooperate with a civilization after part of it almost destroyed everyoneâs trust?
And with a fifth, still-unknown civilization, perhaps the question is:
can we communicate with a form of life that may not separate language, body, technology, and environment the way we do?
Each species expands the universe in a different way.
The Eridians expand the concept of personhood.
The Avelari expand the concept of distance.
The Izerix expand the concept of political responsibility.
The fifth civilization expands the concept of communication itself.
The Avelari are a species created for this AU.
They come from a low-gravity world, with colder light and complex orbits. I imagine them as tall, slender beings, with light movements, large eyes adapted to dimness, and a short layer of fine down covering parts of their bodies.
To humans, they might seem almost fae-like.
But they are not magical.
Their specialty is gravity.
More precisely, gravitational coherence technologies.
They do not create instant portals.
They do not completely break relativity.
Their technology is more limited, more expensive, and more dangerous than that.
But it allows something revolutionary:
reducing the effective distance between systems.
This makes it possible to build slow, unstable, difficult, but functional interstellar corridors.
Without the Avelari, humans and Eridians would remain separated by absurd distances. With them, the possibility of a real interstellar community begins.
The Izerix are another species created for this AU.
They are amphibious or aquatic, connected to ocean worlds, high pressure, salinity, currents, closed ecosystems, and fluid engineering.
But I did not want them to be simply âthe villain species.â
In my idea, there was an expansionist Izerix regime that tried to control resources related to Astrophage, Taumoeba, and interstellar routes. For some Izerix political structures, Astrophage was not only a threat: it had also become part of their energy, military, and economic systems.
So the cure also threatened power.
That is where the conflict begins.
But an entire species cannot be reduced to the worst government it ever had.
Some Izerix supported the regime.
Some were born afterward and inherited distrust caused by a war they did not choose.
I like this idea because it prevents the AU from becoming too clean.
Peace does not erase trauma.
Cooperation does not erase fear.
And an interstellar alliance built after near-extinctions would not be comfortable, perfect, or sentimental all the time.
After the conflict, the Izerix become indispensable in areas such as water treatment, ocean habitats, hyperbaric medicine, aquatic agriculture, closed ecosystems, fluid engineering, cooling systems, and survival on water worlds.
They are, at the same time, a political wound and an essential part of the future.
Concordia of the Four Horizons
With humans, Eridians, Avelari, and Izerix trying to cooperate, the idea of a shared institution emerges:
Concordia University of the Four Horizons.
But Concordia is not only a university.
It functions as a university, embassy, interspecies hospital, research station, cultural archive, translation center, diplomatic space, and first-contact laboratory.
It exists because no civilization can carry the future alone.
Humans are strong in computation, biology, and improvisation.
Eridians are incomparable in materials, pressure, temperature, and extreme habitats.
Avelari master gravitational coherence and routes.
Izerix master fluids, oceans, water, and closed ecosystems.
Each species solves a type of impossibility the others cannot solve alone.
But each one also brings its own fears, interests, traumas, and arrogance.
So Concordia is not a utopia.
It is an attempt to prevent first contact from becoming another war.
To me, this AU works because it does not turn Project Hail Mary into a generic space adventure.
It tries to follow the emotional and scientific consequences of the original story.
Grace and Rocky remain the symbolic heart of everything.
Their friendship proves that a person does not need to have a human face.
They do not need to breathe oxygen.
They do not need to live at a comfortable temperature.
They do not need to speak with words.
They do not need to have a body shaped like ours.
They need to be recognized.
And maybe that is the greatest legacy of the story.
Grace and Rocky did not only save two stars.
They made the universe bigger.
And after that, none of the civilizations involved could ever pretend they were alone again.
So this is the foundation of my AU: a logical continuation of Project Hail Mary, taking into account relativistic time, the full package sent by Grace, the impact of first contact, Earthâs reconstruction, cooperation with Erid, and the later expansion toward the Avelari, the Izerix, Concordia, and a still-unknown fifth civilization.
Does this continuation feel faithful to the spirit of the original story?