Key Characteristics Of Planet K2-18 b According to NASA, K2-18 b has a mass 8.6 times greater than Earth's, and its diameter is roughly 2.6 times that of our own planet. It circles its star within ...

Scientists think a planet may have crashed into Earth 4.5 billion years ago, creating the moon. This alien planet, Theia, was thought to have completely disappeared in the collision.

The James Webb Space Telescope may have detected life-associated gas in the atmosphere of a far-off planet. The news is being greeted with both enthusiasm and skepticism.

K2-18 b orbits a cool dwarf star in the constellation Leo, a place in space that fits all the habitable zone criteria. But the planet’s large size—8.6 times Earth’s mass—may work against life.

K2-18b is an exoplanet, a planet outside our solar system. It orbits the star K2-18 – also known as EPIC 201912552 – a red dwarf star in the constellation Leo.

It may take less than 1,000 years for an advanced alien civilization to destroy its own planet with climate change, even if it relies solely on renewable energy, a new model suggests.