The atmospheric gases around Earth scatter blue light (shorter wavelengths) more than light toward the red end (longer wavelengths) of the visible spectrum ; thus, a blue glow over the horizon is seen when observing Earth from outer space . The Moon is visible in the background.
An atmosphere is a layer of gases that create an astronomical object , that is held in place by the gravity .[ 1] A planet has an atmosphere when the gravity is great and the temperature of the atmosphere is low.[ 2]
↑ Williams, Matt (2016-01-07). "What is the Atmosphere Like on Other Planets?" . Universe Today . Archived from the original on 2019-10-22. Retrieved 2019-10-22 .
↑ Seki, K.; Elphic, R. C.; Hirahara, M.; Terasawa, T.; Mukai, T. (2001). "On Atmospheric Loss of Oxygen Ions from Earth Through Magnetospheric Processes" . Science . 291 (5510): 1939–1941. Bibcode :2001Sci...291.1939S . CiteSeerX 10.1.1.471.2226 . doi :10.1126/science.1058913 . PMID 11239148 . S2CID 17644371 . Retrieved 2007-03-07 .