Full moon 29 or 30 days long. A full moon is often thought of as an event of a full night's duration. This is somewhat misleading because its phase seen from Earth continuously waxes or wanes (though much too slowly to notice in real time with the naked eye). Its maximum illumination occurs at the moment waxing has stopped. For any given location, about half of these maximum full moons may be visible, while the other half occurs during the day, when the full moon is below the horizon. Many almanacs list full moons not only by date, but also by their
Equinox a larger antenna has a narrower beam-width and hence experiences shorter duration "Sun outage" windows.) Equinoxes occur on any planet with a tilted rotational axis. A dramatic example is Saturn, where the equinox places its ring system edge-on facing the Sun. As a result, they are visible only as a thin line when seen from Earth. When seen from above – a view seen during an equinox for the first time from the "Cassini" space probe in 2009 – they receive very little sunshine, indeed more planetshine than light from the Sun. This phenomenon occurs once every 14.7 years on