2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/10589A prototype ultrahigh resolution spectrograph has been built with an adaptive optics telescope. It provides $250,000$ resolving power, 300 Å wavelength coverage and 0.8\% efficiency.Review paper; 13 pages with 7 figs included. Also available from "http://qso.as.arizona.edu/~jge/projects.html"Astrophysicstext