Astral Beacon

These devices are made by the Astral Elves and attuned to the helms of their ships.  They notify that the bearer is in need of rescue.  When activated, any active spelljammer helm of the Astral Elves will hear its call and its location.  The elves will respond with urgency.  It is said that the beacons somehow know of the need of their use ahead of time.  Response typically comes quickly.

The beacon must be in the astral plane, a color pool or in wild space inside a crystal sphere to function.

Notes: Communication