How can a vessel signify distress using its stern light?

A vessel can signify distress using its stern light by making it display a repeated blinking pattern. This form of signaling is recognized internationally as a standard method to indicate an emergency situation or distress. The flashing light serves as a clear and attention-grabbing signal to other vessels nearby, making it evident that immediate assistance may be required.

In the context of distress signals, continuous bright illumination would not convey the urgency or the distress nature effectively, as it does not differentiate from standard operational lighting. Changing the color of the stern light could cause confusion and is not an established method for signaling distress. Turning the stern light off completely would eliminate any visibility and would not announce distress at all. Thus, using a repeated blinking pattern stands out as the most effective signal to convey a state of distress.