People are always worried that alien civilizations will detect the transmissions from our old radio shows and television broadcasts, and send in the invasion fleet. But the reality is that life itself has been broadcasting the existence of life on Earth for 500 million years. It’s the kind of signal that other civilizations could search for as they’re scanning the galaxy. Other forms of life have been giving off signals too, signals we can search for as we discover new exoplanets and wonder if they have life there. Information on ESA's ARIEL missionhttps://www.youtube.com/watch?v=uCTGIxmM-e4Audio Podcast version:ITunes: https://itunes.apple.com/us/podcast/universe-today-guide-to-space-audio/id794058155?mt=2RSS: https://www.universetoday.com/audioWhat Fraser's Watching Playlist:https://www.youtube.com/playlist?list=PLbJ42wpShvmkjd428BcHcCEVWOjv7cJ1GWeekly email newsletter:https://www.universetoday.com/newsletterSupport us at: http://www.patreon.com/universetodayMore stories at: http://www.universetoday.com/Twitch: https://twitch.tv/fcainFollow us on Twitter: @universetodayLike us on Facebook: https://www.facebook.com/universetodayInstagram - http://instagram.com/universetodayTeam: Fraser Cain - @fcain / [email protected]Karla Thompson - @karlaii / https://www.youtube.com/channel/UCEItkORQYd4Wf0TpgYI_1fwChad Weber - [email protected]References:https://www.nature.com/articles/365715a0.pdfhttps://www.sciencemag.org/news/2018/03/asteroid-bound-spacecraft-finds-signs-life-earthhttps://arxiv.org/ftp/arxiv/papers/1907/1907.05245.pdfhttps://news.cornell.edu/stories/2019/07/exoplanet-evolution-astronomers-expand-cosmic-cheat-sheethttps://www.cfa.harvard.edu/~kchance/EPS238-2014/refdata/Seager-red-edge-2005.pdfhttps://www.eso.org/public/news/eso1905/https://arielmission.space/https://www.astrobio.net/news-exclusive/earthshine/