Photosphere but more tenuous corona. Other "surface features" on the photosphere are solar flares and sunspots. Photosphere The photosphere is a star's outer shell from which light is radiated. The term itself is derived from Ancient Greek roots, φῶς, φωτός/"phos, photos" meaning "light" and σφαῖρα/"sphaira" meaning "sphere", in reference to it being a spherical surface that is perceived to emit light. It extends into a star's surface until the plasma becomes opaque, equivalent to an optical depth of approximately 2/3, or equivalently, a depth from which 50% of light will escape without being scattered. In other words, a photosphere is the
Luca (given name) Luca (given name) Luca (also spelt Louca, Luka, Louka, Lucca) is a given name used predominantly for males, mainly in Latin America, Italy, Spain, Portugal, Romania, Russia, Serbia, Slovenia, Croatia, Bulgaria, Greece, Georgia and Armenia. It is derived from the Latin name Lucas, which itself is derived from the Latin word "lux" (light). It may also come from the Latin word "lucus" meaning "sacred wood" (a cognate of lucere). The name is common among Christians as a result of Luke the Evangelist. Similarly, the name Luka is also commonly found as a male given name in Eastern Europe and particularly