Kids
Universe is everything!
telescope at astroshop
Last Moon Landing

  • years
  • :

  • Months
  • :

  • days


  • hours
  • :

  • minutes
  • :

  • seconds

How long will life persevere in our Cosmos?

One of the most mortifying aspects of our Cosmos is the knowledge that all things will eventually pass away. New stars and stellar systems, although are likely to keep forming for many billions or even trillions of years to come, their rate of formation is on the decline, with the present star-formation rate only about 3% of what it was at its extreme some 11 billion years ago. Planets like Earth orbiting around stars like the Sun, while pretty common today, will be awfully rare in the far future. And the longest-lived stars, even if they possess Earth-sized planets around them, might be poor candidates for supporting life because of their extraordinarily active behavior.

At certain point in the far future, the last living world in the Universe will meet its demise, signaling an end to what we know as biological activity within our universe. But when in fact will this occur? And when and where will the last likelihoods for intelligent life persevere? That’s what most of us want to know.

When we attempt to put the pieces of the puzzle together, the following opportunities for life are presented:

  • For the stars that already exist, the lowest-mass ones will become livable only after hundreds of billions or even trillions of years have passed, and may remain livable for up to ~1014 (100 trillion) years.
  • For the stars that haven’t taken shape yet, it’s possible that new star-formation will bring with it new opportunities for life, extending up to ~1017 (100 quadrillion) years into the future.
  • And for the stars that will ultimately form from the mergers of brown dwarfs, they may continue igniting for up to 1021 (one sextillion) years into the future, before gravitational interactions eliminate what we think of as “galaxies” from the picture completely.

All of this comes along with a considerable extent of uncertainty and unknowns. After all, Earth, even today, remains the only world known to us where life has ever arisen and continues or has discontinued to thrive. The prospects for life, at least as we understand it, remain diverse and ubiquitous, and should be probable even far into our Universe’s cosmic future, even if our cosmic home doesn’t remain habitable for much longer. In a Universe with so many biochemical possibilities and so many worlds — past, present, and future — it would be stupid to assume that the way things unfolded here on earth represent the only reasonable pathway to successful arising of life.

Ingredients for a habitable planet

If you desire to have life arise in the Cosmos, a planet (or world, in the case of a livable moon, for instance) might not be absolutely necessary, but it is necessary that the cosmos provides a great environment where life’s emergence is welcomed by a slew of friendly conditions. That means that some amount of chemical enrichment — i.e., a great enough fraction of elements weightier than hydrogen or helium — required to have been created before the formation of the star and stellar system you’re looking at. In 2022, the total confirmed exoplanet count passed 5000 for the first time ever, and an amazing set of facts arose by analyzing which stars had planets around them at all:

  • nearly all of the planets, 98.2% of them, were present around stars that had no less than 25% of the heavy element content present in the Sun,
  • the rest 1.8% of the planets were present around stars that had between 5% and 25% of the Sun’s heavy element content,
  • and that no planets at all were discovered around stars with fewer than 5% of the heavy elements content present in the Sun.

If you desire to have a rocky world that gives life a home for surviving and thriving, presence of enough heavy elements is needed, and that places limits on where, in the evolved galaxies throughout the contemporary Universe, such planets are capable of forming.

Stars and habitability

Planets afford the raw elements from which biochemical reactions for life become possible, but another required ingredient for life’s advent is a source of energy. While a star might not be the only option for providing such a source — we are well aware that the Sun provides the energy that powers almost all forms of life on Earth. Choosing to have a star power the life on a world, however, places enormous restrictions on the types of life-friendly worlds that can arise.

Comments

Leave a Reply

Your email address will not be published. Required fields are marked *

Enter Captcha Here : *

Reload Image