3. Aurora (l.c.) a radiant emission from the upperatmosphere that occurs as luminous streamers, bands, etc., caused when air molecules are excited by charged particles from the solar wind.
1. (noun)dawn, dawning, morning, aurora, first light, daybreak, break of day, break of the day, dayspring, sunrise, sunup, cockcrow the firstlight of day "we got up before dawn"; "they talked until morning"
2. (noun)aurora an atmospheric phenomenon consisting of bands of light caused by charged solar particles following the earth's magnetic lines of force
3. (noun)aurora the Romanpersonification of the dawn of day; the goddess of the morning. The poets represented her a rising out of the ocean, in a chariot, with rosy fingers dropping gentle dew
[Transcriber's note: Solar wind, streams of electrons and protons, interacting with the earth's magnetic field causes aurora. Neither electrons (1897) nor protons (1920) were known in 1892. The SovietsatelliteLunafirst measured the solar wind in 1959. Eventoday increased understanding of solar and auroral phenomenon continues.]