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  • Is it possible we should be looking for life-supporting planets a little differently? Maybe. And maybe

  • that’s a good thing.

  • Hey guys, Amy here for DNews, and one of the most compelling things were doing in space

  • is looking for other Earth-like planets that could harbour life orbiting other stars.

  • When we look for life on exoplanets, we typically look for Earth-like planets in Earth-like

  • places, that is, terrestrial planets that orbit their star’s habitable zone, that

  • magic zone where water can exist as a liquid on the surface.

  • But new research from Cornell University says we might want to broaden our search.

  • For young solar systems, the habitable zone around a host star can actually be much further

  • from that star than previously thought. That’s because young stars are hotter; stars gradually

  • cool as they age. And this is good news in the search for exoplanets because it’s easier

  • to detect planets slightly farther away from their stars.

  • And because stars can cool for up to 2.5 billion years, it's possible that life could begin

  • on a planet during its star’s early life when the star’s habitable zone is further

  • away because it’s much hotter. As the star cools and the habitable zone shrinks, that

  • life could theoretically move to the planet’s subsurface or underground oceans. So there

  • could be life on planets well outside a star’s current habitable zone.

  • But there are other factors at play here, like if a runaway greenhouse effect is triggered.

  • This happens when a planet absorbs more energy from its star than it can radiate back to

  • space, which can lead to a rapid evaporation of surface water. But that doesn’t mean

  • the planet will be forever lifeless. A planet could still become habitable if water somehow

  • arrives after the runaway phase ends, like a late heavy bombardment of water-rich asteroids.

  • That’s what happened to the Earth. Some of our water arrived after this early runaway

  • phase from a heavy bombardment of water-rich asteroids.

  • So when it comes to looking for life on other planets, looking at nascent systems around

  • young stars might be a better way to look.

  • It doesn’t change things immediately, but are you guys excited at what widening our

  • search for life on other worlds might reveal?

  • Let us know in the comments below or you can catch me on Twitter as @astVintageSpace. And

  • don’t forget to subscribe for more DNews every day of the week.

Is it possible we should be looking for life-supporting planets a little differently? Maybe. And maybe

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