92% of Earth-like worlds are yet to be born, study says

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A new theoretical study has suggested that Earth was one of the first planets to bear life as 92 per cent of Earth-like worlds as yet to be born.

Researchers at Space Telescope Science Institute (STScI) in Baltimore, Maryland, carried out an assessment of extensive data collected by NASA’s Hubble Space Telescope and Kepler space observatory to suggest that compared to all the planets in the universe, Earth was born quite early.

Analysis of data from Hubble has effectively helped researchers create a sort of ‘family album’ of galaxy observations that allows puts the star formation in universe on a timeline and map them as the galaxies grew. Initially, after the Big Bang, galaxies and stars were forming at a much faster rate, but the fraction of the universe’s hydrogen and helium gas that was involved was very low.

If we see the star formation rate today, it is much lower than 10 billion years ago, but when it comes to leftover gas, there is plenty compared to initial life of universe, suggesting that the process of star and planet formation will continue for a long time in future – for trillions of years.

“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.

Based on analysis of Kepler data, researchers suggest that there are plenty of Earth-sized planets in our own galaxy The Milky Way. 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.