The lava sensor is a device placed by an unknown party, likely the Chozo or Space Pirates, on Tallon IV. It is marked in concept art, but whether it corresponds to anything in Metroid Prime is unknown. Some may be involved in triggering gameplay events. Judging from the concept artwork that is its sole appearance, it may be present in Elder Hall Access or another room in the Magmoor Caverns. Alternatively, it could be positioned inside or near the lava-filled, superheated Magma Pool in the Chozo Ruins. The presence of "Chozo screens" in the same concept art would seem to suggest so, but there are no such screens in the Magma Pool, nor is there any Chozo architecture in the Magmoor Caverns.