Final answer:
Dr. George R Carruthers invented a unique spectrograph for use on the moon that captured the first UV images of Earth, showing the hydrogen atmosphere, polar auroras, and airglow belt.
Step-by-step explanation:
One of Dr. George R Carruthers' credited inventions is a spectrograph designed specifically for lunar use. This instrument played a crucial role in capturing ultraviolet (UV) images of astronomical features from the moon, where the Earth's atmosphere does not interfere. Its most notable achievement was taking the first UV photographs of the Earth, revealing the hydrogen atmosphere, polar auroras, and the tropical airglow belt in stunning detail. Dr. Carruthers also personally trained astronauts on how to use this device, further illustrating his hands-on approach to his inventions.