High Andean air above Cusco thins haze and sharpens southern deep-sky targets. Altitude cold and thin oxygen matter as much as cloud decks for long sessions near the Sacred Valley.
Wet-season afternoons build storm towers that often clear for brilliant post-midnight skies.
Peru · Andes · ~13.5°S · ~3400 m
Tonight is 22 Oct, times in America/Lima (GMT-5), computed with astronomy-engine for 13.53° S, 71.97° W. Climate: NASA POWER monthly means, 2001-2020, cloud and rain averaged over the whole day.
Check the live Tonight score for Cusco (cloud, dew, transparency, and astronomical dark), then read the hourly cloud timing chart and moonless dark window on this page.
Use the best clear window clock times after astronomical darkness, and prefer moonless hours when deep-sky contrast matters.
Tonight (22 Oct) the moonless dark window in Cusco runs from 3:13 AM to 4:05 AM (GMT-5). This hub also shows moonrise, moonset and illumination; open Dark Sky Window for the full ephemeris card.
Tonight (22 Oct) astronomical darkness in Cusco runs from 7:00 PM to 4:05 AM (GMT-5). This hub lists sunset, civil, nautical and astronomical dusk and the matching dawn times, plus when the Moon and planets are highest. Astronomical darkness starts when the Sun is 18° below the horizon.
ISS passes are spottable near dusk or dawn when the sky is dark and the station is still sunlit. This page lists the next spottable pass when available.