Did We Arrive Early To The Universe’s Life Party?

Article Updated: 26 Sep , 2016
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The Fermi Paradox essentially states that given the age of the Universe, and the sheer number of stars in it, there really ought to be evidence of intelligent life out there. This argument is based in part on the fact that there is a large gap between the age of the Universe (13.8 billion years) and the age of our Solar System (4.5 billion years ago). Surely, in that intervening 9.3 billion years, life has had plenty of time to evolve in other star system!

However, new theoretical work performed by researchers from the Harvard-Smithsonian Center for Astrophysics (CfA) offers a different take on Fermi’s Paradox. According to their study, which will appear soon in the Journal of Cosmology and Astrophysics, they argue that life as we know it may have been a bit premature to the whole “intelligence party”, at least from a cosmological perspective.

For the sake of their study, titled “Relative Likelihood for Life as a Function of Cosmic Time“, the team calculated the likelihood of Earth-like planets forming within our Universe, starting from when the first stars formed (30 million years after the Big Bang) and continuing into the distant future. What they found was, barring any unforeseen restrictions, life as we know is determined by the mass of a star.

The Very Large Telescoping Interferometer firing it's adaptive optics laser. Credit: ESO/G. Hüdepohl

The Very Large Telescoping Interferometer firing it’s adaptive optics laser. Credit: ESO/G. Hüdepohl

As Avi Loeb – a scientists with the Harvard-Smithsonian Center for Astrophysics and the lead author on the paper – explained in a CfA press release:

“If you ask, ‘When is life most likely to emerge?’ you might naively say, ‘Now’. But we find that the chance of life grows much higher in the distant future. So then you may ask, why aren’t we living in the future next to a low-mass star? One possibility is we’re premature. Another possibility is that the environment around a low-mass star is hazardous to life.”

Essentially, higher-mass stars – i.e. those that have three or more times the mass of our Sun – have a shorter life-span, which means that they will likely die before life has a chance to form on a planet orbiting them. Lower mass stars, which are a class of red dwarfs that have 0.1 Solar masses, have much longer lifespans, with some astrophysical models indicating that they may stay in their main sequence phase for six to twelve trillion years.

In other words, the probability of life existing in our Universe grows over time. For the sake of their study, Loeb and his colleagues concluded that certain red dwarfs that are in their main sequence today could likely live for another 10 trillion years. By this time, the probability that life will have developed on some of their planets increased by a factor of 1000 over what it is today.

Hence, we could say that life as we know it – i.e. carbon-based organisms that evolved on Earth over the course of billions of years – emerged early in terms of cosmic history, rather than late. This might explain why it is that we haven’t found any evidence of intelligent life yet – maybe it just hasn’t had enough time to emerge. It’s certainly a better prospect than the possibility that they were killed off during the early phases of their star’s evolution (as other researchers have suggested).

NASA's James Webb Space Telescope, scheduled for launch in 2018, will be capable of measuring the spectrum of the atmospheres of Earthlike exoplanets orbiting small stars. Credit: NASA, Northrop Grumman

NASA’s James Webb Space Telescope, scheduled for launch in 2018, will be capable of measuring the spectrum of the atmospheres of Earthlike exoplanets orbiting small stars.
Credit: NASA/Northrop Grumman

However, as Dr. Loeb explained, the team also determined that there was an alternative to this hypothesis, which has to do with the particular risks faced by plants that form around low-mass stars. For instance, low-mass stars emit strong flares of UV radiation in their early life, which could adversely effect any planet orbiting it by stripping away its atmosphere.

So, in addition to life being premature on Earth, its possible that life on other planets is being wiped out before they have a chance to reach maturity. Ultimately, the only way to know for sure which possibility is correct is to continue hunting for Earth-like exoplanets and conducting spectroscopic searches of their atmospheres for biosignatures.

In this respect, missions like the Transiting Exoplanet Survey Satellite (TESS) and the James Webb Space Telescope will have their work cut out for them! Loeb also published a similar study titled “On the Habitability of Our Universe” as a preface for an upcoming book on the subject.

The Harvard-Smithsonian Center for Astrophysics, located in Cambridge, Massachusetts, is a joint collaboration between the Smithsonian Astrophysical Observatory and the Harvard College Observatory. It’s scientists are dedicating to studying the origin, evolution and future of the universe.

Further Reading: CFA, arXiv

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16 Responses

  1. r1xlx says:

    Instead of spending a vast fortune studying unreachable stars and galaxies maybe you should all be looking under your feet at earthworms and try figure out how they prove Earth and the Universe is very young and Noah’s Flood really did happen worldwide just 4,400 years ago.
    The worms make fools of all of you who believe you is evolved from monkeys/fish/pondslime.

    • BCstargazer says:

      fools for following the evidence instead of an immoral fairy tale ?

    • Jeffrey Boerst says:

      “Instead of spending a vast fortune studying unreachable stars and galaxies maybe you should all be looking under your feet at earthworms and try figure out how they prove Earth and the Universe is very young and Noah’s Flood really did happen worldwide just 4,400 years ago!
      The worms make fools of all of you who believe you is evolved from monkeys/fish/pondslime! Bwahahahahahahahahaha!”

      https://66.media.tumblr.com/b90ea891f25f1ea3dce343a29eb90bca/tumblr_nzbz3ePWmO1uzae1ko1_500.gif

    • Smokey says:

      r1xlx: Claims that Noah’s flood happened a specific number of years ago, or that the Earth/Universe formed only a few thousand years ago cannot be backed up with Biblical text, & those who try to use Biblical genealogies to “date” past events end up having to fill in a lot of blanks using no more than their imagination.

      I understand you’re probably just trolling, but on the off-chance that you actually do believe in the so-called “Good Book,” try actually reading what it says rather than parroting what you’ve heard. Doesn’t it say somewhere that “the truth will set you free?” In that case, Genesis Ch. #1 alone proves unequivocally that planet Earth existed in some way before the “Genesis Event,” and that the universe we see today had to have been here before the Earth. Also, there is no count of the time spent in the Garden (Adam’s age at Abel’s birth is in post-Garden years), so an Earth billions of years old is still possible, even granting every word printed in the Bible as factual, not just an interesting bedtime story.

      If you’re going to tout Scripture, then at least tout what’s written, not what you’ve just heard someone say.

  2. thomasguide says:

    I don’t think this is really vaild, there are too many variables to make this assumption. We don’t know if any type of life can exist in red dwarf planetary systems. Until we have some type of evidence we need to concentrate on looking at Earth type planets around yellow stars. Red dwarf planets are most likely always going to be tidally locked to their stars which allows only a small sliver of the planet that can be habitable. Can life exit there? Can life evolve there? Can there be intelligent life?We just don’t know. It’s rather arrogant to say that we are first and the rest of the galaxy just needs more time.

    • jasonalpha says:

      That’s right Thomas, Even if we don’t see evidence of life by radio or optical or other methods yet to be discovered, it will only be when we have had a few hundred years of exploring the galaxy in warp driven star-ships that we will be able to say either way… the galaxy is vast and we are only in one of the spiral arms .. i think it’s way too early to know what out there. We haven’t even stepped out onto the planets of our own solar system yet.

      • Torbjorn Larsson OM says:

        I find it ironic that Fermi’s own answer to the Fermi Question implies that – interstellar travel – is not likely to happen. And we can already see why, it is far cheaper to explore for life – if not *all* life – from here.

    • Torbjorn Larsson OM says:

      If by “always tidally locked” you mean around half of them (the rest being in or near other resonance orbits, like Mercury) and by “a small sliver of the planet that can be habitable” you mean “likely all of the planet” (as described in recent climate models), well, yes, they are a little bit less statistically.conducive to be habitable I haven’t read the paper in full yet, but I assume Loeb et al used the latest knowledge.

      • thomasguide says:

        I have not read that half of them please provide some evidence to back up that claim. As far as I know, red dwarfs and their planets are small and the planets are tidally locked. If you have evidence besides climate and planet models I would definitely take a look. Yes the sliver, where it’s not too hot and not too cold. The sunny side would boil and the dark side would freeze, so no the entire planet cannot be habitable.

        There is a good read on it on Wikikpedia
        “Habitability of red dwarf systems”

      • Smokey says:

        @thomasguide: I agree with your comments about the level of speculation involved here, so I’d like to specifically address the “death lock” scenario, that every close-orbiting exoplanet MUST be tidally locked to its star, and that such locking NECESSARILY prevents habitability.

        This idea conflicts with recent work which has shown that even tidally locked worlds can (not “will”) produce habitable conditions, and has further found that exoplanets with atmospheres will likely NOT be tidally locked at all: [http://physicsworld.com/cws/article/news/2015/jan/15/exoplanets-could-avoid-tidal-locking-if-they-have-atmospheres]

        From that article: “…A planet [with an Earth-like atmosphere] orbiting a red-dwarf star that is 60% as massive as the Sun does not suffer tidal locking, even if it is only a third as far from the star as Earth is from the Sun.” It goes on to say that a planet with a thicker atmosphere still rotates freely even at much closer distances, and that even “a tidally locked planet could also support life, because previous studies have found that an atmosphere can ferry heat to the night side, so that the air does not freeze and disappear.”

        Finally, in our own solar system, Mercury has no atmosphere, orbits a much larger star at the same studied distance, & is not tidally locked to the Sun. All of this calls both the inevitability & the finality of the “death lock” scenario into question, barring future observations.

      • thomasguide says:

        I read that article and it is promising but it’s based on computer modeling. So in other words we really don’t know. But it is rather arrogant of humans to proclaim we got here first don’t you think? We have been wrong on just about everything in our history about space. Earth was not the center of the universe, the sun didn’t revolve around the Earth, our solar system is not the only one with planets etc… Our Sun and planets formed 5 billion years ago but the universe is 14 billion years old. No other life formed in that first 9 billion years?

  3. elvigy says:

    “…the team calculated the likelihood of Earth-like planets forming within our Universe, starting from when the first stars formed (30 million years ago) and continuing into the distant future.”

    That’s obviously a typo as the first stars formed billions of years ago, right?

  4. Torbjorn Larsson OM says:

    Interesting science, but I note tt doesn’t reference Fermi’s Question. Which by the way was rejected as a paradox (the Hart-Tipler conjecture) already by Fermi’s own answer – that interstellar travel is hard – as described in a Universe Today article: http://www.universetoday.com/119735/beyond-fermis-paradox-ii-questioning-the-hart-tipler-conjecture/ .

  5. chfosmith says:

    Dear r1xlx, You are the victim of one of the translation errors in the Bible.
    The translation error in the King James version that reads days, is as famous as the translation error Martin Luther made when he wrote Red Sea instead of Sea of Reeds. The more accurate translation comes out as a concept that is between the English words periods and phases.
    I would also suggest that you read the books that were not included in the Bible. Doing so provides a lot of insight into other misunderstandings.

    • BCstargazer says:

      so are the passages about human sacrifices, genocides, murder, rape, incest and slavery translation mistakes too?,

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