Night sky or good binoculars, the planets appear as discs demonstrating finite size, and it is possible to observe orbiting moons which cast shadows onto the host planet's surface. Venus is the most prominent planet, often called the "morning star" or "evening star" because it is brighter than the stars and often the only "star" visible near sunrise or sunset, depending on its location in its orbit. Mercury, Mars, Jupiter and Saturn are also visible to the naked eye. Earth's Moon is a grey disc in the sky with cratering visible to the naked eye. It spans, depending on its exact location,
Stars and planetary systems in fiction Federation during the mid-23rd century). The primary was a Class F star. Magnitude of this star was +5, which was the same brightness as Sol. This was a Federation system, with at least one planet being an affiliate. Proxima Centauri, part of a triple star system with Alpha Centauri A and B, is the nearest-known star to the Solar System. Even though it is known to be a flare star, a disproportionate number of early fiction titles are dedicated to Proxima Centauri, as the destination of humanity's first interstellar voyage. A planet in Proxima Centauri's habitable zone was detected in