Observing Desk - tonight's target list, checked against the sky

Paste an observing target list - names with RA and Dec, optional priorities and minutes - choose the site and the local evening date, and the browser computes the night for free before you sign in: sunset, the three twilights, the dark window and its length, the Moon's phase, rise, set and share of the dark window, and for every target its rise, transit with altitude, set, the window above your altitude floor, best altitude and airmass (Pickering 2002), Moon separation and an observable / marginal / unobservable verdict, with an altitude chart. Two lanes over the same list: PLAN orders the night into observing windows with reasons, dropped targets, gaps, risks and a checklist; CHECK reads the draft schedule you already wrote row by row against the same ephemeris and rewrites the rows that fail. Every time and altitude the model writes is re-read against the browser's own engine and disagreements are shown. Engine after Meeus, verified against astropy 8 on 401 checks (stars within 0.6 arcmin, twilight within 2 s); geometric altitudes, no refraction. Derived from the agent skill @k-dense-ai/astropy (k-dense-ai/scientific-agent-skills, MIT); not affiliated with the authors or the Astropy Project.

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