Hello. If one’s goal was to contact a technologically superior extraterrestrial being (or a group of beings, or a civilization), which domain(s) of astronomy should one specialize in precisely? 1) Which type of astronomy should one specialize in? Computational astronomy Experimental astronomy Instrumental astronomy Observational astronomy Theoretical astronomy 2) Which particular subfields of astronomy should one specialize in? Archaeoastronomy Astrobiology Astrochemistry Astrometry Astroparticle physics Astrophysics Cosmochemistry Cosmology Exoplanetology Extragalactic astronomy Galactic astronomy Orbital mechanics Physical cosmology Planetary geology Planetary science Solar astronomy Space exploration Space physics Stellar astronomy 3) Which radiation should one observe? Radio Infrared Visible-light (optical) Ultraviolet X-ray Gamma-ray Cosmic rays Neutrino Gravitational wave Note that I said “technologically superior”, so discovering microbial extraterrestrial life doesn’t cut it at all. Also note that I said “contact”, so discovering a super-advanced extraterrestrial being more than 50 light years away probably doesn’t cut it either because you’ll never be able to “contact” them and get an answer within your lifetime; except if the technologically superior extraterrestrial being knows how to time travel, but since we don’t know if that’s even physically possible it might be a little risky to bet on the feasibility of time travel. Thanks in advance for your answers.