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Hazes are common in known planet atmospheres, and geochemical evidencesuggests early Earth occasionally supported an organic haze with significantenvironmental and spectral consequences. The UV spectrum of the parent stardrives organic haze formation through methane photochemistry. We use a 1Dphotochemical-climate model to examine production of fractal organic haze onArchean Earth-analogs in the habitable zonesof several stellar types: themodern and early Sun, AD Leo (M3.5V), GJ 876 (M4V), $\epsilon$ Eridani (K2V),and $\sigma$ Bo\"otis (F2V). For Archean-like atmospheres, planets orbitingstars with the highest UV fluxes do not form haze due to the formation ofphotochemical oxygen radicals that destroy haze precursors. Organic hazesimpact planetary habitability via UV shielding and surface cooling, but thiscooling is minimized around M dwarfs whose energy is emitted at wavelengthswhere organic hazes are relatively transparent. We generate spectra to test thedetectability of haze. For 10 transits of a planet orbiting GJ 876 observed bythe James Webb Space Telescope, haze makes gaseous absorption features atwavelengths $<$ 2.5 $\mu$m 2-10$\sigma$ shallower compared to a haze-freeplanet, and methane and carbon dioxide are detectable at $>$5$\sigma$. A hazeabsorption feature can be detected at 5$\sigma$ near 6.3 $\mu$m, but highersignal-to-noise is needed to distinguish haze from adjacent absorbers. Fordirect imaging of a planet at 10 parsecs using a coronagraphic 10-meter classultraviolet-visible-near infrared telescope, a UV-blue haze absorption featurewould be strongly detectable at $>$12$\sigma$ in 200 hours.

Pale Orange Dots: The Impact of Organic Haze on the Habitability and Detectability of Earthlike Exoplanets