Accreting
The process by which an object grows larger by gravitationally pulling in and accumulating surrounding material, like gas, dust, or debris.
The gradual accumulation of matter onto a celestial body or object through gravitational attraction. In astronomy, this typically describes how stars, planets, and black holes grow by drawing in surrounding gas, dust, or other material. The infalling matter often forms a rotating disk around the object before being absorbed, releasing energy in the process that can make the system visible across vast distances.
What this means in real life
When a black hole pulls gas from a nearby companion star, the gas spirals inward in a glowing disk before crossing the event horizon—this steady feeding process is accretion, and the light it produces is often how astronomers detect otherwise invisible black holes.
What it isn’t
Accretion is not a sudden collision or merger between two objects. It describes continuous, gradual growth as smaller particles are drawn in over time, not a one-time impact event like when two galaxies crash together.
Commonly misused online
Science enthusiasts sometimes use 'accreting' to mean any kind of cosmic gathering or clustering, but the term specifically requires gravitational pull causing material to fall onto and become part of a central object—not just objects drifting near each other in space.
Based on 1 reference source, including primary sources. Last verified August 3, 2026.