Lo Último

Si eres Autor prueba la opción Entrada Nueva en la pestaña Entradas. Utiliza Chrome para ver el blog completo.

Date de alta como Autor en Universo Mágico Público

Comunidades para disfrutar de la Astronomía: Universo Mágico - Astronomy Lab - Space Roads

Colecciones de Google Plus para disfrutar del Universo: Astronomía en fotos - Astronomía en vídeo

Owl Nebula

Owl Nebula

This extraordinary bubble, glowing like the ghost of a star in the haunting darkness of space, may appear supernatural and mysterious, but it is a familiar astronomical object: a planetary nebula, the remnants of a dying star. This is the best view of the little-known object ESO 378-1 yet obtained and was captured by ESO’s Very Large Telescope in northern Chile. ESO 378-1 lies 3500 light-years away in the constellation Hydra. Image credit: ESO.
Nicknamed the Southern Owl Nebula, this shimmering orb is a planetary nebula with a diameter of almost four light-years. Its informal name relates to its visual cousin in the Northern Hemisphere, the Owl Nebula (Messier 97). ESO 378-1, which is also catalogued as PN K 1-22 and PN G283.6+25.3, is located in the constellation of Hydra (The Female Water Snake).

Like all planetary nebulae, ESO 378-1 is a relatively short-lived phenomenon, lasting only a few tens of thousands of years, compared to a typical stellar lifetime of several billion years.

Planetary nebulae are created by the ejected and expanding gas of dying stars. Although they are brilliant and intriguing objects in the initial stages of formation, these bubbles fade away as their constituent gas moves away and the central stars grow dimmer.

For a planetary nebula to form, the aging star must have a mass less than about eight times that of the Sun. Stars that are heavier than this limit will end their lives in dramatic fashion assupernovae.

As these less massive stars grow old they start to lose their outer layers of gas to stellar winds. After most of these outer layers have dissipated, the remaining hot stellar core starts to emit ultraviolet radiation which then ionises the surrounding gas. This ionisation causes the expanding shell of ghostly gas to begin to glow in bright colours.

After the planetary nebula has faded away, the leftover stellar remnant will burn for another billion years before consuming all its remaining fuel. It will then become a tiny — but hot and very dense ‐ white dwarf that will slowly cool over billions of years. The Sun will produce a planetary nebula several billion years in the future and will afterwards also spend its twilight-years as a white dwarf.
Planetary nebulae play a crucial role in the chemical enrichment and evolution of the universe. Elements such as carbon and nitrogen, as well as some other heavier elements, are created in these stars and returned to the interstellar medium. Out of this material new stars, planets and eventually life can form. Hence astronomer Carl Sagan’s famous phrase: “We are made of star stuff.” Starseeded

No hay comentarios:

Publicar un comentario en la entrada

Comentar es un incentivo para el Autor