In the tabernacle, the incense is offered as prayers before God. In Numbers 16:46,47 we see Moses telling Aaron to take his censor and run through the assembly to make atonement for them. I understand offering prayers to God on behalf of these people but it states that this was to make atonement for them. Any insights on this?

In the tabernacle, the incense is offered as prayers before God. In Numbers 16:46,47 we see Moses telling Aaron to take his censer and run through the assembly to make atonement for them. I understand offering prayers to God on behalf of these people, but it states that this was to make atonement for them.

And Moses said to Aaron, "Take your censer, and put fire on it from off the altar and lay incense on it and carry it quickly to the congregation and make atonement for them, for wrath has gone out from the LORD; the plague has begun." (Numbers 16:46, ESV)

What does "atonement" mean in this context?