Games like First Contact
Games like First Contact include The Message from Deep Space, Outer Wilds, Kerbal Space Program, Papers, Please, and Deliver Us The Moon. We matched them by the tags players give First Contact on Steam (Aliens, Science, Sci-fi, Adventure, and Pixel Graphics): closest matches first, and among equally close ones the better-known games.

The Message from Deep Space
Shared: Science · Aliens · Sci-fi

Outer Wilds
Shared: Adventure · Space · Mystery

Kerbal Space Program
Shared: Science · Space · Simulation

Papers, Please
Shared: Indie · Pixel Graphics · Simulation

Deliver Us The Moon
Shared: Adventure · Sci-fi · Indie

Out There Somewhere
Shared: Pixel Graphics · Adventure · Puzzle

There Is No Game: Wrong Dimension
Shared: Adventure · Puzzle · Indie

Machinika Museum
Shared: Sci-fi · Puzzle · Indie

Observation
Shared: Adventure · Sci-fi · Indie

OneShot
Shared: Pixel Graphics · Indie · Puzzle

The Invincible
Shared: Adventure · Sci-fi · Space

The Rewinder
Shared: Adventure · Pixel Graphics · Puzzle

Murders on the Yangtze River
Shared: Adventure · Puzzle · Indie

while True: learn()
Shared: Science · Puzzle · Indie

FEZ
Shared: Puzzle · Pixel Graphics · Indie

The Swapper
Shared: Sci-fi · Puzzle · Adventure

SPORE™
Shared: Science · Simulation · Space

CrossCode
Shared: Pixel Graphics · Puzzle · Indie

Beat Cop
Shared: Pixel Graphics · Adventure · Indie

Baba Is You
Shared: Puzzle · Indie · Pixel Graphics

Thimbleweed Park™
Shared: Adventure · Pixel Graphics · Puzzle

The Talos Principle
Shared: Sci-fi · Puzzle · Adventure

Strange Horticulture
Shared: Puzzle · Mystery · Adventure

SpaceChem
Shared: Puzzle · Indie · Sci-fi