NASA : Most Earth-Like Worlds Have Yet to Be Born, According to Theoretical Study .- La mayoría de los mundos similares a la Tierra aún no se han nacen, Según Estudio teórico

Hola amigos: A VUELO DE UN QUINDE EL BLOG., Tierra llegó temprano a la fiesta en el Universo en evolución. Según un nuevo estudio teórico, cuando nuestro sistema solar nació hace 4.6 millones de años, sólo el ocho por ciento de los planetas potencialmente habitables que formarán jamás en el universo existía. Y, el partido no se acabará cuando el sol se funde en otros 6 mil millones de años. La mayor parte de los planetas - 92 por ciento - aún no se han llevado.
Esta conclusión se basa en una evaluación de los datos recogidos por el telescopio espacial Hubble de la NASA y la espacial Kepler observatorio planeta-caza prolífico.
"Nuestra motivación principal fue comprender el lugar de la Tierra en el contexto del resto del universo", dijo el autor del estudio, Peter Behroozi del Space Telescope Science Institute (STScI) en Baltimore, Maryland, "En comparación con todos los planetas que nunca formarán en el universo, la Tierra es en realidad muy pronto ".

More information.......
http://www.nasa.gov/feature/goddard/most-earth-like-worlds-have-yet-to-be-born-according-to-theoretical-study

arc of Earth-like planets against the cosmos

This is an artist's impression of innumerable Earth-like planets that have yet to be born over the next trillion years in the evolving universe.

Credits: NASA, ESA, and G. Bacon (STScI)

Looking far away and far back in time, Hubble has given astronomers a "family album" of galaxy observations that chronicle the universe's star formation history as galaxies grew. The data show that the universe was making stars at a fast rate 10 billion years ago, but the fraction of the universe's hydrogen and helium gas that was involved was very low. Today, star birth is happening at a much slower rate than long ago, but there is so much leftover gas available that the universe will keep cooking up stars and planets for a very long time to come.

"There is enough remaining material [after the big bang] to produce even more planets in the future, in the Milky Way and beyond," added co-investigator Molly Peeples of STScI.

Kepler's planet survey indicates that Earth-sized planets in a star's habitable zone, the perfect distance that could allow water to pool on the surface, are ubiquitous in our galaxy. Based on the survey, scientists predict that there should be 1 billion Earth-sized worlds in the Milky Way galaxy at present, a good portion of them presumed to be rocky. That estimate skyrockets when you include the other 100 billion galaxies in the observable universe.

This leaves plenty of opportunity for untold more Earth-sized planets in the habitable zone to arise in the future. The last star isn't expected to burn out until 100 trillion years from now. That's plenty of time for literally anything to happen on the planet landscape.

The researchers say that future Earths are more likely to appear inside giant galaxy clusters and also in dwarf galaxies, which have yet to use up all their gas for building stars and accompanying planetary systems. By contrast, our Milky Way galaxy has used up much more of the gas available for future star formation.

A big advantage to our civilization arising early in the evolution of the universe is our being able to use powerful telescopes like Hubble to trace our lineage from the big bang through the early evolution of galaxies. The observational evidence for the big bang and cosmic evolution, encoded in light and other electromagnetic radiation, will be all but erased away 1 trillion years from now due to the runaway expansion of space. Any far-future civilizations that might arise will be largely clueless as to how or if the universe began and evolved.

The results will appear in the October 20 Monthly Notices of the Royal Astronomical Society.

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, in Washington.

For images and more information visit:

http://www.nasa.gov/hubble

http://hubblesite.org/news/2015/35

Donna Weaver / Ray Villard

Space Telescope Science Institute, Baltimore, Maryland

dweaver@stsci.edu / villard@stsci.edu

Last Updated: Oct. 20, 2015

Editor: Karl Hille