[Lonesome in Massachussets]

The moon was once a ring of particulates flung out by the collision.

And will again be. Currently the moon is receding from the earth and will continue to do so until the lunar month and earth day are both about 47 current earth days long. Then the Moon will gradually spiral in on the earth, its orbit becoming ever smaller, until falls within the Roche limit at which point the earth's gravity will disrupt it and it will quickly become a ring, or a series of rings around the earth.

[RadioAstronomer]

However, that will take almost 50 billion years and the Sun will consume both long before that can happen.

[ItsTheMediaStupid]

And will again be. Currently the moon is receding from the earth and will continue to do so until the lunar month and earth day are both about 47 current earth days long. Then the Moon will gradually spiral in on the earth, its orbit becoming ever smaller, until falls within the Roche limit at which point the earth's gravity will disrupt it and it will quickly become a ring, or a series of rings around the earth.

Aren't you a bearer of good news? Hopefully our descendants will have the technology to evacuate the earth. Though the way things are going I am not so sure.