An “exoplanet” is a planet outside the solar system, and today’s Google Doodle, remarkably timely (and cute), celebrates yesterday’s announcement (published in Nature; I haven’t yet read the paper) of seven exoplanets found orbiting around a single star called “Trappist-1”, forty light years away:
As NASA reports, there are seven planets, all roughly the size of Earth, though the star—their “sun”—is considerably smaller than ours (it’s about the size of Jupiter). The excitement about this announcement comes from the fact that all seven of the planets might have water in some form, but three of them are in the cushy “Goldilocks zone”, where temperatures and the presence of liquid water on a rocky planet might be amenable to the evolution of life. Here’s NASA’s depiction of the planetary system (click to enlarge):
And an imagined view of the Trappist-1 sun from one of the exoplanets (note that, unlike our Sun, the star is pinkish):
As far as I can tell, the Spitzer infrared telescope that detected these planets didn’t actually see them; they were detected by perturbation of the signal. They will, however, be investigated more intensively with the “James Webb Space Telescope,” which will be able to detect crucial things like the presence of oxygen—almost a sure sign of life. That scope will be launched next year.
Now do these planets have any life on them? How the hell do I know? I can’t even say with any degree of certainty whether there’s life elsewhere in the Universe, though I think the odds favor it. But on these three: who knows? They’re too far away to send probes, but maybe we can now aim radio signals there, just in case there’s intelligent life.
But they’re just three planets; as Sean Carroll wrote on his Facebook page, urging caution, “Evergreen caution: the observable universe could have 10^25 planets, and the chance that any one of them has life might be 10^-100.” (That’s 0.00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001). Still, the possibility that we’ll find life out there, which fascinates people, especially evolutionary biologists, means that we’ll cling to the smallest probabilities.
In the meantime, HuffPo, which has been driven literally insane by Donald Trump, took the opportunity to drag him into this finding. You’ll find this headline on its Science page (click on screenshot to see article), which just gives a bunch of stupid tweets. I am amused at how crazed that site has become about Trump. One would think that there’s nothing else going on in the world.
“They’re too far away to send probes, but maybe we can now aim radio signals there, just in case there’s intelligent life.”
In the webcast someone mentioned that SETI did point to the star system. They didn’t find anything.
Could be they didn’t achieve technical efficiency until 30 yrs ago, in which case the signal hasn’t arrived yet, wishful thinking.lol
I smell schadenfreude about Earth and man in these findings and promotions. Not from scientists, who exalt the pure knowledge and spirit of discovery, but from people with low happiness, people not digging in and solving problems here.
“Well, the population on earth is out of control, we’re destroying the planet, we’re going to need to go somewhere else. Maybe I can get free lunch there, because no one is giving it to me here.”
Then they read “merely” 40 light years, or “only” 40 light years, and think “wow, we could manage a journey of 40 years.”
Here’s what I emailed to one of those people, who was ready to purchase a ticket.
Speed of light is 186,000 miles per second.
Speed of Apollo/Saturn at escape velocity: 6 miles per second.
So, that’s 6 vs 186,000
That’s a multiple of 27,900 times.
Meanwhile, it is impossible to accelerate a space ship to the speed of light. It would require all the energy in the universe to do it. Not to mention it would take an equal amount of energy to stop.
People want to escape reality.
Not if we get an infinite improbability drive.
You rang?
Just as long as you promise to insult them all in alphabetical order.
Tempting…
🙂
Let’s not forget that the Fermi Paradox could well cancel out the Drake Equation
And the respective filters.
“People Want To Move To The Newly Found Planets To Escape Donald Trump”
They didn’t even move to Canada like they said they would.
🙂
We are only weeks into Trump’s presidency and the relentless snarking is just boring.
Admittedly there’s an ocean between me and Trump but even if I was American I’d be sick of it.
There’s a point when you just tune out for your own sanity
Well, yes, one could hope that the fires would be dying down by now. There’s just one problem – the Orange One keeps lighting more.
cr
Hmm…I would have gone with:
“Extremelely Low Probability of Trump Being Elected President Vastly Improves Chances For Life Elsewhere In Universe”
Although a couple of dozen refugees have walked over the boarder into Canada in the past couple of weeks. They are expecting more when the weather gets warmer.
Better build a wall, stat.
“When [the USA] sends its people, they’re not sending their best. They’re sending people that have lots of problems, and they’re bringing those problems with [them]. They’re bringing drugs. They’re bringing crime. They’re rapists. And some, I assume, are good people.”
Well, HuffPo wants an exodus to the exoplanets.
But if the only life forms there are exoskeletal, this might seem exotic but would compromise the colonists’ exogamy. If Trump’s fans (for whom no one yet has coined an exonym) follow them, they might need to hold an exorcism. Also, the cost of the journey would be exorbitant.
Excellent!
All of these planets are expected to be tidally locked (the relevant forces fall off strongly with distance, and they are very close because it’s a red dwarf). So probably not good conditions for life.
Astronomy has made some remarkable discoveries in the past few years, but in terms of Earth-like planets we’re still unfortunately looking “under the lamppost” rather than “where we think the keys are.”
There is some speculation that other factors such as the sizes, number and proximity of the planets, may result in resonances other than straight forward 1 to 1 for some of the planets. But modeling will take time and data will be slow to accumulate.
Also, the jury is still well out on how likely, or not, being tidally locked is to preclude life.
Regarding where we are looking, agreed. Technology limits where we can look such that the places most closely matching the circumstances our one real (rather than a model) example (Earth) enjoys are currently beyond our reach.
In my opinion nearly all exoplanet findings to date should be taken with a grain of salt. Not about whether or not there is a planet, but the details. I’m betting that our ideas about the distribution of various planet types still have a lot of changes ahead. Of all the planet detections to date only 5 or so have been direct observations. All the rest have been indirect using methods that yield extremely small signals. I’m betting that when technology improves to the point where we can begin to verify previous detections by more direct means there will be a lot of corrections made and surprises found.
In a tidally locked planet one face might always be too hot and the other face always too cold, which means that there will have to be a transition zone that will always be at just the right temperature. So there’s no reason to discount life on a tidally locked planet. Indeed it might be easier conditions for life than a planet with large day/night and seasonal temperature changes.
It’s just the beginning though with exoplanet searches. 20 years from 1 to 3000, exponentially discovered. And then to extrapolate. The implications are profound.
Astronomy has made some remarkable discoveries in the past few years, but in terms of Earth-like planets we’re still unfortunately looking “under the lamppost” rather than “where we think the keys are.”
Too true. Right now we have a strong selection bias towards planets close to their stars. But, for those planets to be in their star’s habitable zone, the star must be dim, i.e. a red dwarf. Unfortunately, red dwarfs dump out uncomfortable amounts of high-ultraviolet and X-ray radiation, probably making the evolution of life impossible near them.
Most likely, life can only evolve on planets orbiting G-type stars like our sun—maybe F-type (marginally larger) and K-type (marginally smaller) too. But those types only make up a little more than a fifth of the total stars in our galaxy (most are red dwarfs). So that’s a fraction that cuts down the drake equation substantially. And detecting planets at the right distance from them is difficult.
I’m hopeful though to see what ol’ J-Webb can discover.
“forty light years away” — So if there’s someone there watching broadcasts from planet earth, they’re seeing the opening days of the Carter administration. Far from perfect, but at least they’re getting a better sense of the decency, fairness, and common sense of the American people than anyone watching contemporaneously.
In reality the bad news is that if ther’s someone watching broadcasts from when we are emitting electromagnetic signals, they know we are used to conduct fratricidal wars even with nuclear strikes. Understood? They know we have nuclear weapons and we have no qualms about using them against our species and on our planet ….What do you think they can consider as?
This system is allegedly only around ~500 million years old, so I don’t know what anyone would expect SETI to find there. Perhaps, if our species lasts long enough, we can figure out how to get to .5 the speed of light, or make warp drive a thing and get there within a generation or so. It would pose a long term foothold in the universe for humankind as it burns so slowly that TRAPPIST may last about 10 trillion years. But that’s not going to happen in my lifetime.
But why did they call it TRAPPIST? Is someone thinking of opening an interstellar brewery?
Better a brewery than a colony of cloistered monks.
TRAPPIST is the name of a Belgian optical telescope that originally found the star.
TRAnsiting Planets and PlanetesImals Small Telescope.
A project driven by the Department of Astrophysics, University of Liège.
Two 60 cm twin telescopes, – one in Morocco and the other in the Atacama in northern Chile. They discovered two or three of the planets in this system some time ago by photometry. These would have been impossible to discover through photometry had the plane of the planets’ orbits not intercepted our place in space.
It is impressive that the dimming of Earth-size planets eclipsing a very dim, Jupiter-size star at 39 light-years is measurable by a telescope only 60 cm in diameter. The detector costs about USD 11 000. The mount costs roughly USD 20 000. The telescope tube+optics is around USD 65 000. The 5 m aluminium dome maybe about USD 50 000. Altogether, the price of a good used car (Lamborghini 🙂
SETI didn’t find anything? Or they just didn’t bother replying, why do we think if life is on any of these exoplanets, one, they have the tools, two, they want to be found. We have South American hunter gatherers who have given or at lest tried to give the rest of us, a big fuck off and leave us alone. Like the christen hoards racing around the planet spreading the word, we are gods gift to the rest of the universe… Google should have put a “do not disturb ” sign out at the end. Contact us when you’ve grown up and showing a little respect for your own planet and it’s creatures.
Given the round-trip for signals traveling at light-speed would be 80 years, the most recent events we could be receiving a response to would be the Berlin Olympics and the outbreak of the Spanish Civil War.
No surprise they’d want us to leave them alone.
The first message we received from outer space in Carl Sagan’s Contact was Hitler’s opening speech from the Berlin Olympics transmitted back to us.
Yes, in Contact the signal came from a robotic transmitter/receiver orbiting Vega, 25 light-years away, 50 year round trip in addition to some processing time.
Let’s see life imitates art.
Stephen Baxter’s Proxima is set on an exo-planet in the Goldilocks Zone of Proxima Centauri.
I read it about a year before the discovery of an exo-planet in that same system.
The novel was still fresh enough in my mind that when the news broke I could talk confidently about tidal locking and sub-solar points.
It bothers me that NASA often releases such detailed “artists’ conceptions” with announcements of this nature. I applaud Professor Coyne for labelling the images above as “concepts” but I have seen many other media sources fail to do so, which I fear leads many people to think the appearance of these planets is already known in such detail as is suggested by the first picture (“look at planets f and g! They have oceans! And b has active volcanoes!”). Better in my opinion to just show a series of blank circles depicting the relative sizes of the planets.
However, this is an absolutely fascinating discovery, as all seven of these planets are closer in size to the earth than any planet in our solar system other than Venus.
This has long bothered me too. Circles or disks are unambiguous and informative. Also beneficial would be error bars or graphical elements that show margins of error in an intuitive way.
I wonder how SC arrives at such a low probability for life?
Good question. I don’t see how any probability can be assigned since we have only one life observation and it doesn’t count (degrees of freedom.)
Maybe he explains it somewhere.
It’s not an estimate, he’s simply illustrating that having lots of planets doesn’t automatically mean that life is probable.
He’s just adding zeros to the number of planets to point out that life may be too rare?
I think we get that without having a number to look at.
I wish I hadn’t replied that way. It was snarky and SC’s use of such a number as an illustration was fine.
When it comes to extra-terrestrial life, I feel a bit hypocritical re faith v facts. I am fairly certain extra-terrestrial life exists because it seems incredible to me that earth would be unique. Yet the facts of the matter is that there is zero evidence, so I shouldn’t feel so certain.
This is *exactly* my thinking on the issue. As an ex-religious crazy, I absolutely loathe taking anything on faith, or without evidence; on the other hand, as you say, “it seems incredible to me that earth would be unique.”
My current position relies on convergent evolution, and what little I know about abiogenesis and systems chemistry (thanks to Addy Pross’ superb book What is Life: How Chemistry Becomes Biology”). Given the uniformity of natural law, life should come into existence wherever the conditions are right, much as it did here. I’m banking on the fact that our methods of detection (apart from radio) are pretty crude, which is why we haven’t detected any little green men yet. Furthermore, my natural (and well-founded) pessimism, leads me to the conclusion that the resolution of the Fermi Paradox is the obvious, though sad one–once a civilization reaches roughly our level of technology, it soon drives itself extinct through some combination of overpopulation, environmental destruction, and technological hubris (nuclear or biological weapons, etc.), with most probably a big assist from microorganisms which, as we know, evolve a whole lot more rapidly than we do.
One step further: I’m also reasonably confident–again, based on convergent evolution–that any life forms on a planet somewhat similar to ours would themselves be somewhat similar to ours. Water-dwelling creatures would have fins; eyes, wings, thorns, and other organs highly useful to survival would be widely found, there would be lots of parasites, etc.
Yes, that is pretty much how I rationalize it, too. Chemistry is universal and life comes about through chemistry.
Even ignoring how to interpret “life comes about through”, there’s a problem, alas, with that claim: what compounds are formed is a function of ambient conditions.
“In the meantime, HuffPo, which has been driven literally insane by Donald Trump…”
With the greatest respect, I do hope that was ironical. I think our PCC(E) has been driven into hyperbole by PuffHo.
OK, I know, I’m being pedantic about ‘literally’ amongst other things… No disagreement that PuffHo has gone bananas…
cr
As a fellow pedant, that caught my eye too.
BTW, I was going to ask what happened to your “y”, but then tried a little impersonation experiment, and now understand.
Yes, WordPress treats me with Procrustean malevolence 😉
cr
The Wikipedia article on the star begins: “TRAPPIST-1, also known as 2MASS J23062928-0502285, is an ultra-cool dwarf star”
I guess that is meant in both senses of the term…
Does anyone have a source for Sean Carroll’s figures?
I’m skeptical of the Drake Equation sometimes, but I do think it is good as a thought experiment to get one thinking about the right parameters.
If there is a technological civilization, developped before us (not likely but also not impossible), and aliens are watching our broadcasts, becouse of they are at 40 light-years away, they know we have neclear weapons and they know that we have used them here on Earth against our species….so better for them stay in silence, monitor us and maybe prepare to defend ……