Perihelion

First Signal

A psychological sci-fi thriller · Visual novel

47:12
Chapter I

One night. One signal. Everything changes.

Dr. Tomáš Horák is an astronomer on a routine night shift at the Ondřejov Observatory near Prague. Tired. Alone. Drinking cold coffee and counting the hours until dawn.

At 01:14, his instruments detect an anomaly. An interstellar object entering the solar system — and it's decelerating. By 45 kilometers per second. Nothing in nature does that.

In fourteen days, it will be visible to the naked eye. Before that happens, Horák must decide: who to tell, who to trust, and how far he's willing to go to protect the truth.

SYS: SEQUENCE COMPLETE.
OBJECT: A/2025-X1
DELTA-V: -45.2 KM/S
MANEUVER: DECELERATION

THERMAL SIGNATURE: EXTREME
SOURCE: REAR OF OBJECT

WARNING: MEASURED VALUES DO NOT MATCH KEPLERIAN LAWS.
“Asteroids don't brake. Nothing in space brakes unless it hits something. And there's nothing out there.”
Cast

Every decision shapes who stays.

Dr. Tomáš Horák
Astronomer · Protagonist
Tired, pragmatic, dry humor. He didn't ask for this. He was just covering someone's shift. Now the weight of first contact rests on his shoulders.
☕ 🍩
Petr Dvořák
Colleague · Mirror
Observant, grounded, funny. He's not an astronomer — he's better. He's the one who notices what Horák misses. And he always brings doughnuts.
Dr. Mašková
Government · Threat
Calm. Precise. Dangerous — not because she threatens, but because she never needs to. She always knows more than she says. Her tablet holds secrets; her silence holds more.
Kateřina
Partner · Anchor
She knows when Horák is lying. She came when he asked. Whether she stays depends on what you tell her — and what you don't.
DARMSTADT
Hans
ESA · Voice only
You never see his face. Only hear his voice on encrypted calls from Darmstadt. He has data from Paranal. He offers collaboration. He says: “Structures are slow. The object is not.”
FAQ

Questions

What kind of game is this?
Perihelion: First Signal is a psychological sci-fi thriller in the form of a visual novel. Built in Ren'Py. Your choices shape the story across 8 chapters — who you trust, what you reveal, and how you interpret the signal.
How long is the game?
A single playthrough takes approximately 3–4 hours. With multiple endings and branching paths, total content is 8–10 hours.
Is the science real?
As real as possible. The detection process, delta-v calculations, observatory procedures, and global response are grounded in actual astronomy. The object's behavior is inspired by 'Oumuamua and speculative interstellar probe concepts.
Will there be a sequel?
Perihelion is planned as a trilogy. First Signal is a complete, self-contained story — but the questions it leaves unanswered are deliberate.
Platforms?
PC (Windows, Mac, Linux). Ren'Py engine.
Who is behind this?
Perihelion: First Signal is a solo project by Martin Sejkora.