You and up to eight willing creatures within range project your astral bodies into the Astral Plane (the spell fails and the casting is wasted if you are already on that plane). The material body you leave behind is unconscious and in a state of suspended animation; it doesn't need food or air and doesn't age.

A target’s astral form resembles its body in almost every way, replicating its game statistics and possessions. The principal difference is the addition of a silvery cord that trails from between the shoulder blades of the astral form. The cord fades from view after 1 foot. If the cord is cut—which happens only when an effect states that it does so—the target’s body and astral form both die.

Your astral form can freely travel through the Astral Plane and can pass through portals there leading to any other plane. If you enter a new plane or return to the plane you were on when casting this spell, your body and possessions are transported along the silver cord, allowing you to re-enter your body as you enter the new plane.

Any damage or other effects that apply to an astral form have no effect on the target’s body and vice versa. If a target’s body or astral form drops to 0 Hit Points, the spell ends for that target. The spell also ends for you and your companions when you use your action to dismiss it. When the spell ends, the affected creature returns to its physical body, and it awakens.

When the spell ends for a target who isn’t dead, the target reappears in its body and exits the state of suspended animation.