It is the smallest and innermost planet in the Astroneer solar system, and you can access it by utilizing a Spaceship.
On the surface of the planet there are holes with worm-like monsters in them that cannot be killed or dug out.
If you were to fall in, you will die.
Due to its slow rotation, the day/night cycles on the Radiated planet take more time than the ones on the Terran planet. This makes it challenging to sustain your electricity level with only Solar Panels, so it is advised to use Wind vanes and Wind turbines to generate power. Conveniently, Radiated planets have permanent wind locations on the surface or just above the surface. If you place your Wind vanes and Wind turbines in the appropriate locations you will always have power. Also one of the poles on this planet will always have sunlight. All of the planets are above the plane of the star, this makes accessing sunlight as simple as finding the pole that is at the very bottom portion of the planet but due to the procedural generation of planets you might find that the perfect spot is at the top of a mountain or on a floating pod making it difficult to expand your base.
All of the resources present in the game generate in veins on or right below the surface of the planet.
This makes the Radiated planet very valuable, in the sense that you can collect resources like Lithium, Coal, and Titanium very swiftly.
The average time it takes for a day/night cycle to pass is 20 minutes.