For much longer than the nine years Centauri Dreams has been in existence, I’ve been waiting for the announcement of a planetary discovery around Centauri B. And I’m delighted to turn the first announcement on this site over to Lee Billings, one of the most gifted science writers of our time (and author of a highly regarded piece on the Centauri stars called The Long Shot). Lee puts the find into the broader context of exoplanet research as we turn our gaze to the nearest stars, those that would be the first targets of any future interstellar probes. On Thursday I’ll follow up with specifics, digging into the discovery paper with more on the planet itself and the reasons why Centauri B was a better target than nearby Centauri A. I’ll also be offering my own take on the significance of the find, which I think is considerable.
by Lee Billings
For much of the past century, astronomy has been consumed by a quest to gaze ever deeper out in space and time, in pursuit of the universe’s fundamental origins and ultimate fate. This Old Astronomy has given us a cosmological creation story, one which tells us we live in but one of innumerable galaxies, each populated with hundreds of billions of stars, all in an expanding, accelerating universe that began 13.7 billion years ago and that may endure eternally. It’s an epic, compelling tale, yet something has been missing: us. Lost somewhere in between the universe’s dawn and destiny, passed over and compressed beyond recognition, is the remarkable fact that 4.5 billion years ago our Sun and its worlds were birthed from stardust, and starlight began incubating the planetary ball of rock and iron we call Earth.
Somehow, life emerged and evolved here, eventually producing human beings, creatures with the intellectual capacity to wonder where they came from and the technological capability to determine where they will go. Uniquely among the worlds in our solar system, the Earth has given birth to life that may before the Sun goes dim reach out to touch the stars. Perhaps, on other worlds circling other suns, other curious minds gaze at their night skies and wonder as we do whether they are alone. In this coming century, a New Astronomy is rising, one that focuses not on the edge of space and the beginning of time but on the nearest stars and the uncharted worlds they likely hold. It will be this New Astronomy, rather than the Old, that will at last complete the quest to place our existence on Earth within a cosmic context.
In a major leap forward in this enterprise, today a European planet-hunting team announced their discovery of an alien world about the same mass as Earth. This alone would be noteworthy, for of all the “exoplanets” now known beyond our solar system, only a very few, and very recently, have been shown to at all resemble our own. But there is more to the story. This particular exoplanet resides in a three-day orbit around the dusky orange star Alpha Centauri B, a member of the Sun’s closest neighboring stellar system. There are two other stars in the system as well, the yellow Sun-like star Alpha Centauri A and the red dwarf star Proxima Centauri.
Astronomers began discovering exoplanets about two decades ago, finding at first a few per year. Since then, the pace of discovery has dramatically accelerated. Today there are more than 750 confirmed exoplanets, and a single NASA mission, the Kepler spacecraft, has detected more than 2,300 additional candidates that await confirmation. Most of these exoplanets are far too large, too hot, or too cold to support life as we know it, but a handful appear to be “Goldilocks” worlds the right size and the right distance from their stars where liquid water could flow in streams and pool in seas, worlds where carbon-based organisms could potentially thrive. The discovery of more Goldilocks worlds appears inevitable — statistics from the Kepler mission and other sources suggest that somewhere between ten to thirty percent of stars harbor potentially habitable planets. Among the planet-hunters, the question is no longer whether life exists elsewhere in the universe, but rather how far removed the next-nearest living world might be.
At a distance of just over 4.3 light years, the stars of Alpha Centauri are only a cosmic stone’s throw away. To reach Alpha Centauri B b, as this new world is called, would require a journey of some 25 trillion miles. For comparison, the next-nearest known exoplanet is a gas giant orbiting the orange star Epsilon Eridani, more than twice as far away. But don’t pack your bags quite yet. With a probable surface temperature well above a thousand degrees Fahrenheit, Alpha Centauri B b is no Goldilocks world. Still, its presence is promising: Planets tend to come in packs, and some theorists had believed no planets at all could form in multi-star systems like Alpha Centauri, which are more common than singleton suns throughout our galaxy. It seems increasingly likely that small planets exist around most if not all stars, near and far alike, and that Alpha Centauri B may possess additional worlds further out in clement, habitable orbits, tantalizingly within reach.
Anyone in the Southern Hemisphere can look up on a clear night and easily see Alpha Centauri — to the naked eye, the three suns merge into one of the brightest stars in Earth’s sky, a single golden point piercing the foot of the constellation Centaurus, a few degrees away from the Southern Cross. In galactic terms, the new planet we’ve found there is so very near our own that its night sky shares most of Earth’s constellations. From the planet’s broiling surface, one could see familiar sights such as the Big Dipper and Orion the Hunter, looking just as they do to our eyes here. One of the few major differences would be in the constellation Cassiopeia, which from Earth appears as a 5-starred “W” in the northern sky. Looking out from Alpha Centauri B b and any other planets in that system, Cassiopeia would gain a sixth star, six times brighter than the other five, becoming not a W but a sinuous snake or a winding river. Cassiopeia’s sixth bright point of light would be our Sun and its entire planetary system.
Image: Alpha Centauri as seen by the Cassini orbiter above the limb of Saturn. Credit: NASA/JPL/Space Science Institute.
Despite its close proximity, as with nearly all other known exoplanets, Alpha Centauri B b is as yet unseen. It was detected indirectly, via a periodic 50-centimeter-per-second wobble its orbit raises in the motions of its star, in a painstaking process that took four years of nightly monitoring and careful analysis. The wildly successful Kepler mission finds the bulk of its candidates by a different technique, looking for the minuscule diminution of a star’s light when, by chance, a planet in its orbit transits across the star’s face and casts a shadow toward Earth. Both of these discovery methods can constrain the most basic properties of a planet: its orbit, its mass, and perhaps its size and bulk composition. But neither can readily reveal whether or not any potentially habitable planet is actually a place much like Earth. To do that really requires taking a planet’s picture. Even if that picture amounted to only a meager clump of pixels, astronomers might discern within it a planet’s rotational period — the length of its days — as well as clouds, oceans, and continents. The reflected planetary light would also contain spectroscopic signatures of atmospheric gases. Carbon dioxide would suggest a rocky planet, and water vapor would hint at oceans or seas. Detecting oxygen and methane — gases produced on Earth by living things — would further suggest that the distant planet was not only habitable, but inhabited.
Viewed over interstellar distances in visible light, the Earth is some ten billion times fainter than the Sun, meaning that for every photon bouncing off Earth’s atmosphere or surface, ten billion more are flying out from our star. About the same ratio would apply for any habitable planet around Alpha Centauri’s stars. Distinguishing such faint planetary light from that powerful stellar glare is rather like spotting a firefly hovering a centimeter away from the world’s most powerful spotlight, when the spotlight is in Los Angeles and you are in New York. To see the firefly, that overwhelming ten-billion-to-one background light must be suppressed.
Amazingly, on paper and in laboratory studies, astronomers have already devised multiple ways to do exactly this for potentially Earth-like planets that may exist around nearby stars. Most of these methods require an entirely new multi-billion-dollar space telescope, though a few proposals exist to augment NASA’s upcoming James Webb Space Telescope with starlight-suppressing technology at an estimated cost of $700 million. Considering that three years ago a film about life on Alpha Centauri’s planets — James Cameron’s Avatar — grossed some $2 billion in box-office receipts, it stands to reason there is public appetite to spend at least that much on space telescopes to search for the real thing.
Matt Mountain, the director of the Space Telescope Science Institute in Baltimore, Maryland, likes to quip that the discovery of life beyond our solar system could be to this coming century what Neil Armstrong’s lunar footprints were to the last. Yet today NASA is not seriously funding any life-finding telescopes, and has no real plans to do so in the future. The agency instead is spread thin and lacking any unified direction, strapped for cash and struggling to avoid obsolescence while it maintains the International Space Station, builds a new fleet of rockets to replace the retired Space Shuttles, and completes the James Webb Space Telescope. Yet obsolescence is precisely what NASA will embrace if it fails to invest now in the next giant leap required for this New Astronomy. Of all the scientific institutions and agencies upon this planet, at present NASA alone has the resources to build a telescope capable of directly imaging and characterizing any Earth-like planets around nearby stars. Unless it does so, as the list of potentially habitable planets grows long in years to come, all that shall grow along with it will be our ignorance of what those distant worlds are actually like and what may live upon them.
Meanwhile powerful, influential Old Astronomy, which has revolutionized our understanding of the universe at its largest scales, is wary of the New, and at times has acted quite deliberately against it. Alas, government-funded Big Science is too often a zero-sum game, one in which money that could go toward looking for life on exoplanets around nearby stars would be taken from cosmological efforts to study far-distant galactic clusters and the expansion of the universe. In a perfect world we would fully fund both quests simultaneously. But our world — with its economic instabilities, rising temperatures, growing populations, and plummeting biodiversity — seems to grow more imperfect by the day, in ways that no knowledge of dark energy or dark matter is likely to ever assuage. The New Astronomy is different. We do not yet know whether planets like ours and creatures like us are in fact common or rare in the cosmos, but by trying to find out, we will unavoidably learn just how precious our planet truly is. Perhaps, with luck, discoveries following from today’s announcement will help us finally kick off from our small blue footstool, and find our way among the stars.
Lee Billings is working on a book about the search for other Earth-like planets, forthcoming from Penguin/Current next fall.
FINALLY!
Great news, wonderful times!
Congratulations to the team that made this discovery. This is incredibly exciting news and opens up tantalizing new possibilities for destinations of future interstellar probes.
Brilliant! All these years and it finally happened. Bet you are thrilled.
Lets fill out the rest of the system with more discoveries!!
Very nice article, reporting an extremely interesting discovery. One tiny nit to pick: Proxima Centauri is something like a degree away from Alpha Centauri on the sky – only A&B merge into a single pinpoint to the eye, Proxima is well outside that pinpoint.
This is a very exciting discovery- both for being the first Earth-size planet found, and for orbiting Alpha Centauri B! In the near future, I hope to see many more such discoveries, and new telescopes to actually ascertain whether or not any of these planets actually host life.
Such idealistic pursuits seem ever more precarious and unlikely in our imperfect, badly-managed modern world, but ultimately pursuing the faint traces of alien life and seeking ways to reach faraway planets will benefit our planet. Pursuing the faint traces of life in the cosmos will show us just how fragile and precious our small blue world really is, and spur interest in preserving our planet’s biosphere. But, perhaps even more importantly, such efforts are our ultimate expression of being human- of looking up, and wondering what is out there, and then finding a way to find out.
After the first alien planets with biospheres are found, the interest in sending automated probes to these planets- and eventually crewed starships- will mount to a fever pitch. Once we know that a planet orbiting a fairly nearby (cosmically speaking, that is) there exists a planet with an actual biosphere– just think, real aliens!!- we’ll have to find some way to get there, or even just land a small probe with a digital camera to take some pictures. Even if it takes gigawatts of power, kilograms of energy, and over a decade of travel time, someday launching a probe will be both technically possible and quite probably not that expensive to a far future spacefaring society…
Time to extend the Sagan Planet Walk again?
Fantastic news.
1992 – PSR B1257+12
2012 – Alpha Centauri B
This is wonderful news long in coming. Congratulations to the team who made the discovery, hopefully the first of a sizable family awaiting us around the Alpha Centauri system.
Indeed having planets this close to us may be the match to the fire we so need very much.
Imagine the memorable names we’ll be giving those worlds which will endure down the history for as long as the humanity and their descendants live.
“Its.. its… full of… planets!” Nice way to contextualize this tantalizing discovery. In a sense this is the continuation & vindication of planetary astronomy’s 20th century struggle for legitimacy against “real” establishment astronomy.
Congratulations to the research team, and to everyone for working so hard and staying in the fight.
Next, we get the metal bent and start sending some emissaries to check out our new (B)a(b)y (~Alpha Centauri B b).
Very interesting news, the fruit of observations really pushed to the limits.
Shame that it seems compatible with yet another compact system.
This means that NEAT (or similar) should definitely take precedence over any expensive imaging mission, in order to know what is actually possible to image beforehand.
Lee Billings;
This is one awesome article. You could not have stated it better.
Many thanks;
Jim
Excellent post. I am a regular reader and never left a comment. I take this opportunity to congratulate Centauri Dreams for their work. And let’s go!
Double articles on a single day, definitely worth it!
Very big news indeed. It demonstrates that planets can form there and so gives reasonable hope that there will be more. Could be wrong, but I don’t think that this announcement will lead to sufficient funding for an interstellar mission. But if there is even a Mars-like planet there, then there would be the sufficient justification to go.
Amazing and long awaited stuff. However watch everyone go nuts with wild extrapolations and wishful thinking about what comes next.
50cm/s – that’s right on the bleeding edge of what even the amazing HARPS can do. Earth analogues in the Hz? That is going to be soooo tough.
Let’s hope this stirs a hornets nest under some of those moribund space-based mission concepts!
P
I can’t believe this happens within my lifetime.
@Richard Obousy, when is Icarus Interstellar launching its probe? The sooner the better I say.
Paul, I must say this seems a remarkably apt day for a story like this to appear. “Reaching out into other worlds from our desperately overcrowded planet, a series of deep-thrust telescopic probes [??] have conclusively established a planet orbiting the star Alpha Centauri as the only one within range of our technology able to furnish ideal conditions for human existence.”
This is the beginning….
So tantalisingly close and yet so far… the curse of knowledge! Congratulations to all involved.
Perhaps we should be looking at a truly international effort to build an Earth-class planet hunting telescope, such as the Cinderella-like TPF (http://en.wikipedia.org/wiki/Terrestrial_Planet_Finder). Global public interest in finding a planet very much like our own home world could well make the difference in freeing up funds. A larger consortium might be possible than the one backing the ~$2B SKA (http://www.skatelescope.org).
http://www.dailykos.com/story/2012/10/16/1145485/-Alpha-Centauri-Planet-Found-Only-4-3-Ly-Away
Thought you might enjoy more gen public opinion. Looks like this group is ready to go
4.3 light years 2.5% of light gets you there in less than 200 years. Wasnt sun driver 1% ?
Wonderful news!
What an amazing time to be alive!
Great News! Definitely a game-changer for future development in new astronomy.
If we want, we can make this the decade, we can be the generation that made it possible, what the hell is 700 million dollars to improve the already delayed James Webb telescope in order to get back doing first order science. Everyone reading this; do whatever it is in your power to avoid people talking about intelligent design and trying to disprove evolution gain more ground. Church and State were separated for a reason.
It doesn’t matter if after spending that money, it turns out that bad luck had its way one more time, and no other interesting planets are in our “backyard”. As long as there are enough mining materials, we can send intelligent probes ready that after reaching destination, will capture starlight, mine the local minerals and start building a local, but permanent station. We can do this many times with many stars, and at some point, the machines will discover a place that will be habitable, and we will be ready to send a crewed mission, with all the infrastructure ready for us.
it is just a dream now, but after a cosmic blink, we all might awake to it.
Not meaning to be the wet blanket at the star party,
but a hot planet in a three-day orbit is pretty much useless
for the settlement of the Centauri system:
its orbital velocity is high and due to its high temperature
its inventory of fusion fuel will be low as well
(unlike Epsilon Eridani’s gas giant).
The other essential mineral inventory besides fusion fuel
is asteroids, or at least planets with no atmospheres.
At least Alpha B has a confirmed planet,
so hopes for further planets around B and A (and even Proxima)
will keep Centauri’s prospects open for decades to come.
Keep your cosmic fingers crossed for Centauri’s resources.
cant say that in our lifetimes we will be able to see the light of day on any of these oddballs out there . its all good to hear that there is one close but if its too hot then its too hot. its like mars; its a frozen radioactive ball of dust with few interests other than mining in someone elses lifetime. so, why should we spend alot of time amusing ourselves over something that isnt happening just yet ? first thing is we dont have a propulsion system capable of making the trip in less than 22k years, second is we wont be able to get a good look at the atmosphere of any of these exo-giant question marks until we get hubble 3 set up. this will be in only about 20 years. so I wouldnt get your star wars lunch kit packed for a trip to a centauri b just yet
An Infinitude of Tortoises wrote:
[Paul, I must say this seems a remarkably apt day for a story like this to appear. “Reaching out into other worlds from our desperately overcrowded planet, a series of deep-thrust telescopic probes [??] have conclusively established a planet orbiting the star Alpha Centauri as the only one within range of our technology able to furnish ideal conditions for human existence.”
This is the beginning….]
Well, the surface temperature of the planet *does* give new meaning to the immortal words, “The pain…” :-)
Fantastic! What would be a realistic time window to expect a definitive say on the possibility of habitable zone terrestrial planets around either Alpha Centauri A or B? And are the investigators planning to continue to search for that long?
Very good news, but on reflection significant because it rules out one of three scenarios I can think of.
It is likely that stars A and B are not in their primordial orbital configuration. It is possible that an early episode of dynamical relaxation within the crowded birth cluster could have resulted in the ejection of a lower mass star, leaving the two remaining sun-like stars in their high eccentricity, moderately spaced orbit. Depending on the details of the violence, all planet forming material around both stars could have been cleared. This evidently did not happen around at least star B.
The two remaining scenarios are that planets were able to form and survive right out to the present day stability boundaries around both stars, in which case habitable planets could be present; or that planets were only able to survive long-term very close to their primaries.
The present evidence does not distinguish between these two alternatives, but let’s hope for the first.
How about this for a useful suggestion.
100YSS should release a small fraction of that money they are sitting on to fund one of the postdocs doing these observations. It could be justified in starship terms as “target acquisition”. I think it is highly likely that it would be money well spent as I’d bet my bottom dollar on there being more planets around A, B and Proxima awaiting discovery.
Historic moment and excellent article!
I was sincerely moved when I first learned about this news late last night (European time), when it was still in the unofficial and rumour stage.
The ESO news publication:
http://www.eso.org/public/news/eso1241/
And the Nature news article:
http://www.nature.com/news/the-exoplanet-next-door-1.11605
Both are very well and clearly written.
I enjoyed reading this.
But the suggestion that spotting extrasolar planets helps assuage problems here on earth (“economic instabilities, rising temperatures, growing populations, and plummeting biodiversity”) more than studying dark energy and dark matter (“The New Astronomy is different.”) is a bit of a stretch.
Looking for substitute planetary homes now is just as practically irrelevant as studying the big bang, since they are all many hundred years of preparation and travel away in either case. And if we really were serious about making preparations to leave Earth and colonise the galaxy, the most pressing next step is developing robots or other forms of “artificial life” that will do the step for us. Because “we” won’t go anywhere. The ISS plus the Mars rovers together are plenty of evidence that sending tinned primates into outer space is a waste of time and energy, while prolonging our earth-bound senses by robotic remote sensors is fruitful.
And then, with foundational research one never knows what the practical relevance will be once. Today we use general relativity to fine-tune GPS navigation on Earth. Is it clear that a deeper understanding dark matter and dark energy won’t be crucial for managing intergalactical travel? One fine but distant day.
For some reason, it’s the detail about the constellations being (almost) the same that blows my mind. I feel like we’re neighbors already.
Hi Folks;
The way I feel about it, the New Astronomy has a really cool aspect about it because for the most part, planetary evolution and solar system evolution studies and modeling is highly fluid and gas dynamics, electrodynamic-hydrodynamic-plasma physics, chemistry ,and atomic and low energy nuclear physics based. We have already amassed much theoretical and empirical data in all of these fields. Just as we can apply CFD codes and other numerical methods to model climate change on Earth and to model, track, and estimate the path of large storms (and I am looking forward to a harsh winter here in the mid-Atlantic portion of the Eastern U.S. where I live with lots of Nor’ Easters LOL!), we have many theoretical tools to really delve deeply into the dynamics of solar systems and planetary formation. However, there is still room to grow here especially in terms of bio-chemistry and solid state physics. Proverbially speaking, GOD only knows what molecule based life forms especially any ETI would be like. Regarding solid state physics, there is so much uncharted territory in the physics of solids and liquids compressed under millions of atmospheres. I look forward to more basic research to be done at the NIF facility here in the U.S. in regard to extreme pressures acting on macroscopic samples of atomic matter.
This is all obvious to folks who regularly contribute to the comments here at TZ-CD but the ramifications are profound and sometimes overlooked in importance.
Thanks for reading and commenting, folks. Not sure how to reply to specific comments, so just will put a digest here.
Dana – Thanks for pointing out the error — for simplicity’s sake, I fudged the detail of Proxima. To be fair, in actuality Proxima is not visible to the naked eye, so in a way the three stars do still manifest as a single point of light to human eyes viewing Earth’s night sky.
David Grinspoon – “In a sense this is the continuation & vindication of planetary astronomy’s 20th century struggle for legitimacy against “real” establishment astronomy.” YES. This is exactly the bigger story that is happening. Planetary astronomy is the Next Big Thing, and for frankly petty reasons a lot of the “establishment” isn’t thrilled about it. Which is really a pity, because the high degree of public excitement and engagement planetary astronomy presently offers is something that could greatly benefit astronomy as a whole.
Eric – Xavier Dumusque of the HARPS team told Dennis Overbye of the NY Times that finding a 4x Earth-mass planet in Alpha Cen B’s habitable zone could take 8 to 10 years. It wasn’t clear if he meant 8 to 10 years from now or 8 to 10 years of total observations, in which case they’d need another 4-6. Given the spate of new spectrographs soon to come online, I would guess that the next 3-6 years is the reasonable timeframe in which a radial velocity (RV) search would find more rocky planets around Alpha Cen B. Alpha Cen A is a tougher nut to crack because it’s a “noisier” star. I’m not sure how much RV can realistically hope to improve there — it might take space-based astrometry, really. And as for Proxima, to find any planets there using RV you really need a high-precision infrared spectrograph rather than an optical one. Fortunately there are several such instruments set to come online soon. The future is bright for finding more planets around the Centauri stars.
Martyn Fogg: Good points. Indeed, the presence of Proxima in the system’s outskirts has been suggested as a weak (but favorable) constraint on the manner in which Alpha Cen formed and dynamically evolved and the likelihood of their disks producing small planets. Your suggestion re: 100YSS funding is apt, since, as you say, it’s difficult to conceive of only this planet and no more existing around these stars.
Urs Schrieber: The “substitute planetary home” is the most distant and ambitious goal of this sort of research, but it is not the only one. There are other practical or inspirational benefits to be gained. Just one example: Assume this and other discoveries of rocky planets around nearby stars motivates the development and launch of one or more Terrestrial Planet Finder-style observatories, space telescopes capable of directly imaging potentially habitable worlds. The first iteration of such an effort (and there would need to be multiple tiers, alas, this is not a one-shot deal) would probably be a filled-aperture optical telescope. That is, a very large mirror in space. If we develop the technology to deploy 10-to-20-meter mirrors in space, that’s also extremely useful for monitoring the Earth from geosynchronous orbit. One such mirror would give you individual-cloud resolution for nearly an entire hemisphere. Launch 3 or 4 and you suddenly have 24/7 deep awareness. It would be vital for climate modeling, weather forecasting, and much else. Not to mention defense applications.
That’s just one example. There are many more. This isn’t just about spin-offs, though, which cosmology can also supply. This is about astronomers connecting with the public in what seems to be a dawning age of austerity, about astronomy making itself relevant and worthwhile so that it continues to receive public support and funding. The search for life beyond the solar system offers breakthrough potential for really not that much money. I simply do not see similar potential right now in the proposals put forth to refine the cosmological constant by an order of magnitude or to better map the distribution of dark matter in galactic clusters. Full stop.
Martyn Fogg: “It is likely that stars A and B are not in their primordial orbital configuration. It is possible that an early episode of dynamical relaxation within the crowded birth cluster could have resulted in the ejection of a lower mass star, leaving the two remaining sun-like stars in their high eccentricity, moderately spaced orbit.”
A couple of years ago I wondered about this myself. Restricting myself to arXiv (obviously not a comprehensive view of the literature) I could not find: any substantive look at the system’s early dynamics, which might have argued for a configuration more favorable to planet formation; or, any planet forming modeling of the system that did not take as an assumption that the present orbital parameters differed in the distant pass.
Does anyone know of any work done on this topic, other than speculation or what-if scenarios? I’m specifically referring to the Alpha Centauri system, not a more general study.
Lee Billings: “Given the spate of new spectrographs soon to come online, I would guess that the next 3-6 years is the reasonable timeframe in which a radial velocity (RV) search would find more rocky planets around Alpha Cen B. Alpha Cen A is a tougher nut to crack because it’s a “noisier” star. I’m not sure how much RV can realistically hope to improve there — it might take space-based astrometry, really.”
There are already doubts being expressed as to whether the current finding is true or a statistical anomaly. Many of the measurement and target system’s “noise” components are already each greater than 0.5 m/s. I did read through the paper and (to my inexpert eyes) it looks like good work that does adequately remove the likelihood of a false positive.
Since the difficulties will be worse (probably much worse) for a planet that is further out, having astrometry instruments with greater resolution does not seem promising to me. I doubt that even 10 years of observations will result in a statistically-reliable signal. Finding such a planet will probably require a different technique, such as a space-based star shade.
Or we could just travel there and look around. ;-)
This just in: Scientists have just found a gas giant type exoworld orbiting Alpha Centauri B as well. The alien planet appears to have several large moons circling it, one of which has an almost Earthlike environment with massive life form readings.
These same scientists have also detected some unusual minerals on this moon which appear to have superconducting properties.
In other news, the Planetary Resources planetoid mining company has just changed its name to the Resources Development Administration, or RDA. Construction on an interstellar vessel capable of reaching the Alpha Centauri system in just over five years is already underway.
Anyone going to call James Cameron for some seed money on a probe to AC?
@Martyn Fogg – I enjoyed reading your JBIS articles on habitable planets.
In terms of this Alpha Centauri B planet, one worrying thought to add to your list – this planet is roughly the mass of a gas giant’s core. IF this is the core of a gas giant that has lost most of its atmosphere over the last 5 billion + years (it gets about 312x more sunlight than the Earth), then it’s very bad news for any planets in B’s HZ. The migrating gas giant would have probably scattered them on its way in (there are papers showing that stars with hot Jupiters rarely have other planets nearby).
if Alpha Centauri Bb is that close to its parent star, the chances are that is tidally locked. What could we expect to be the temperature in the night side? or are we to assume that at that close distance any atmosphere will be likely ripped off in a few million years?
Thanks for the answer, Lee!
Another question: In the near term, could a “beta version” of the New Worlds starshade be put into LEO for use by the Hubble, so as to image just a handful of the nearest stars? Perhaps this could be a cheaper and quicker way of getting some direct observational data…
I agree with the assessment regarding potential benefits of exoplanet research.
Detecting an alien biosphere(which is not unimaginable in 20-30 years) would be a cultural breakthrough for our civilization and likely spur significant(although probably not overwhelming) investment in space exploration. The consequences for philosophy, theology and other sciences would be enormous too.
I am convinced that having knowledge of alien biosphere, we would be determine to learn more in some way.
The coming possible development of hypertelescopes will likely allow us to gain more knowledge.
As to discovery in Alpha Centauri-this is very good. It would be VERY hard to deny further research on this, and likely will inspire several teams and countries to fund more research on exoplanets and Centauri system itself(I am talking about reasonable research within limits of current budgets).
Regarding interstellar travel-I wouldn’t be so optimistic about habitable planet, but that doesn’t matter. Colonization was never the question, if there is an alien biosphere we won’t colonize it anyway. What’s important is that there is possibility of a “stepping stone” nearby. We could in theory even use such planet for resource gathering, and if there are asteroids or comets in the system, that is enough for any post-human explorers.
But for now-let us think about new telescopes and creating Exoplanet Division in Nasa ;)
Habemus planeta! :-)
Great news, and a great article.
@Eric, Lee Billings:
That “8-10 years” estimate for a habitable-zone planet seems overlong, given that they already announced last year that there was “no planet larger than 4 Earth mass with a period shorter than 300 days” around Alpha Cen B (according to a comment in https://centauri-dreams.org/?p=19798). The habitable zone does not extend far beyond 300 days, as far as I know.
(And there’s also a chance that other ongoing Alpha Centauri studies, like Fischer’s, might find habitable-zone planets quicker than HARPS.)
@FrankH:
B b being a hot Jupiter core seems an improbable “worry” to me. Hot Jupiters are very rare to begin with (only around ~1% of stars). And B’s snow line will be very close to the outer limit of orbital stability (3-4 AU), so the chances of a gas giant even having formed in the system are rather slim IMHO.
steve aka hugh Manchu October 17, 2012 at 1:57
“”cant say that in our lifetimes we will be able to see the light of day on any of these oddballs out there”
“”second is we wont be able to get a good look at the atmosphere of any of these exo-giant question marks until we get hubble 3 set up. this will be in only about 20 years'”
Many of us are in their 20s or 30s, luck willing, we will live to see it if it happens, by around late 20s, there should be another big space telescope mission. Although I am counting on innovative ideas like star shade, or space telescope swarms.
@Martyn Fogg You wrote “100YSS should release a small fraction of that money they are sitting on…”
Martyn, how much money does 100YSS have? I have only heard of them getting US$500,000 in seed money from DARPA. That won’t even buy a concept design for a mission. Time to start collecting donations, or lobbying politicians.
This is terrific news! Trying to figure out the geology and geophysics of these magma planets will be a great challenge as data starts to come in.
Now rooting for the National Ignition Facility team to figure out inertial confinement fusion – and for any other people working on deep-space propulsion, the Alpha Centauri planetary system will be a huge boost.
Eric: Good question. I think a starshade is off the table for Hubble if for no other reason than that the observatory is old and its equipment is breaking down with no plans for another servicing mission. Plus the Hubble is in LEO, as you mentioned, which means there’s more contaminating light bouncing around that will mess with your observations.
People are very seriously talking about putting an internal coronagraph of some sort on the NRO telescope, which may eventually fly as a WFIRST-style mission. I’m not sure if anyone has run all the trades on whether doing something like an external occulter would be more sensible, but from my recent conversations I received the impression that for a WFIRST-kitted NRO an internal coronagraph would be preferable and could bag a small handful of mid-size planets (close-in Neptunes, or, yknow, maybe “super-Earths,” though the data-based distinctions between these categories is uselessly muddy at the moment).