Final answer:
Aerial observations have evolved from a 15-centimeter telescope on a Learjet to the 2.5-meter Stratospheric Observatory for Infrared Astronomy (SOFIA) on a Boeing 747SP, flying high to avoid atmospheric water vapor for clearer infrared imaging.
Step-by-step explanation:
Observations from aircraft provide a unique perspective for various fields of research, including atmospheric sciences, astronomy, and engineering. One significant development in aerial observations was the Stratospheric Observatory for Infrared Astronomy (SOFIA), which features a 2.5-meter telescope on a modified Boeing 747SP aircraft. This advancement builds upon earlier efforts such as the 15-centimeter telescope on a Learjet and a 0.9-meter telescope operating on flights from the Ames Research Center. The high altitude at which these telescopes operate, such as 12 kilometers above the Earth, positions them above approximately 99% of the atmospheric water vapor, permitting clearer and more accurate infrared observations.