72-hour forecast for astronomical observations.
72-hour forecast for astronomical observations. As the oldest product that 7Timer! has ever provided, ASTRO product is mainly intended for astronomical purpose. The forecast range is 3-day and has included several elements that concerns astronomers most - such as cloud cover, astronomical seeing and atmospheric transparency. For details of the forecast method, see Publ. Astron. Soc. Pac., 123, 113, and references therein.