Planets at Tau Ceti, one in the goldilocks zone
A little heavy on the gravity, but hey, you can’t have everything.
They may have found Downbelow. ;)
by CJ | Feb 28, 2013 | Journal | 28 comments
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…and if you won’t ask for it or work for it, you can’t have anything… well not that you’d want, anyway…
I tawt I Tau a Ceti whale….
(Don’t tell Ahab. That guy’s seriously pegged already….)
😀 Great news about Tau Ceti. Planets popping up all over the place. This bodes really well for building stations, maybe colonies, mining, refueling, and so on.
Some big questions though, are harder to answer: How common are “Goldilocks Zone” planets? Of those, how often will they turn out to be suitable for human colonists? Or…is there already life there, how advanced, can we and that life coexist? Big, big question: What if somebody already lives there?
The way things are shaping up, I get the feeling we might know well beforehand if there’s some form of life on a remote star’s planet, and we might have some clue beforehand if they’re intelligent.
(Is it a positive or negative indicator, if they start trying to get us to sign up for interstellar wireless video and galaxy-wide web?)
Seriously, though, either by telescope (unlikely) or directed probes (more likely) it’s starting to look like we’d at least have an idea for any planet with intelligent life similar enough to us that we’d recognize them. (And possibly they’d recognize us….) Though what if it’s alien enough we’re not sure? That seems highly likely too.
But… How likely is it that any other planets’ lifeforms will be so far behind us or so far advanced that there’s no real competition? Or, unhappily, what likelihood they didn’t make it? How many do make it? (Note we haven’t made it off-planet to a stable interstellar / starfaring stage yet.) … How rare are our neighbors, equals, rivals, friends?
Tau Ceti, Gliese 581, several others “nearby” … How many in a hundred light year radius are going to turn out to have (1) planets and (2) one or more planets or moons in the Goldilocks Zone?
Very, very interesting. — And more compelling evidence that it’s worth being out there, exploring, trading and getting resources, and aware and ready in case the neighbors come calling, whatever they might want to do while they visit. … Appeal to enough hot buttons in human nature, and surely *something* will convince the powers that be that getting into space is a good idea.
The “don’t put all your eggs in one basket” theory, as noted by one Capt. ker Pyanfar Chanur, hath its merits, to be sure, for any number of reasons, ours, theirs, nature itself, any reason at all.
Very neat to see Tau Ceti and several others are promising exploration spots.
Some big questions though, are harder to answer: How common are “Goldilocks Zone” planets? Of those, how often will they turn out to be suitable for human colonists? Or…is there already life there, how advanced, can we and that life coexist?
1) Still quite rare in fact. Found a lot of “hot Jupiters”, but in part because most of the earlier finds were based on the star wobbling around the barycenter. The bigger, the closer, the easier to detect. But now they’re looking for transits or occultations. That isn’t so affected by mass or distance, but still, the smaller the planet, the more sensitive our photometry must be.
2) Like Earth, or like Mars? Unknown, but again, probably very rare IMO. Remember, Earth was hostile to life as we know it, water and all, before the blue-green algae transformed the atmosphere–and it was still astromonically the perfect planet. We’ve already considered whether, our CO2 atmosphere at that time could have supported any higher life forms (NOT!) on Shejidan. 😉 Herself’s AUC makes use of a lot of uninhabitable masses, e.g. Kura, Hoas, Meetpoint, Tripoint. Maybe being Earth-like isn’t all important?
3) “Everybody’s got an opinion.” Given it’s like (shall we call it “the post oxygen apocalypse”?) Earth, then as I’ve proposed, basic Chemistry dictates the life should be generally quite recognizable, IMO.
Coexistance? Debatable. It’s debatable whether we can coexist with other species here! 😉
Remember “Godlilocks and the Three Bears”? We might just want to learn how to mind our manners before we get involved in serious housebreaking.
What was it with that Goldilocks girl, anyway? Goes into someone’s house, uninvited, gets into all their stuff, eats their food, and then tries their beds, and … stays around, falls asleep in one bed, and thinks somebody is not gonna be just a wee bit aggravated to find her there?
I mean, come on. Porridge? … Though these must be rather civilized bears, living in a house, sleeping in beds, eating porridge. (Berries and Fish Porridge, maybe? I’m not sure about the cuisine. Well, I don’t know. I do like salmon and tuna and catfish. I like berries. But in porridge? OK, I like Malt-o-Meal too. Maybe it’s an acquired taste.) Goldilocks seemed to acquire the taste.
Possibly Baby Bear was more like Baby-Faced Bear? He seemed only mildly upset that there was a strange girl in his bed. His Mama and Papa Bear, however, were a bit more alarmed, for reasons perhaps understandable in ursine urban communities. After all, the girl waltzed in, shacked up, while the Bear family were all having a nice walk before breakfast. Mama and Papa Bear might well look askance at Baby Bear’s extra-curricular activities, there.
Though perhaps Baby Bear got an unfair ursine upbraiding. After all, he would have the usual ursine urges, if perhaps quite unusual taste in intimate companionship.
But apparently, it all worked out. Maybe it was that unusual taste for that porridge and other ursine charms. Perhaps Goldilocks has persuasive talents or better manners than we have been led to believe. There didn’t seem to be further complaints from any of the Bear family or Goldilocks.
It would seem to be preferable to that whole flap over the Three Pigs and that rather pushy Wolf.
Personally, I wonder just what sort of Wolves these were. Very bad attitudes, dismal relations with all the neighbors, quite infamous reputations.
However, many Wolves seem more eager to avoid such ignoble entanglements, as long as they can hunt and pursue Wolfish interests like any other members of the community. After all, some of them even raise man-cubs, not that it’s their responsibility to do so, but they were willing to put up with the odd idiosyncracies there.
And what is it about threes? Three Bears, Three Pigs, Three Men in a Tub? (Not that I’m complaining, mind you. If three men want to get in a tub, I suppose that’s up to them.)
I guess the Seven Dwarves in that commune out there are the exception. Fine by me, though I don’t what that one guy is so Grumpy about.
Ah well, who’s to know the real workings of such folk, eh?
One wishes the Bears and their new family member or house guest well. — Okay, okay, I might try the porridge, though honestly, I think I’d prefer the fish and berries and porridge separately.
At least it’s not Peas Porridge. I quite definitely would prefer my peas and porridge separate, thanks. To each his own, or hers, its, gtst’s….
BCS, I get the MOM’s Best cereals, they’re inexpensive, but are in a box, rather than the usual Malt-O-Meal bags. The cinnamon squares are pretty good.
I’m wondering what you do in your spare time when you’re not meditating on Grimms’ Fairy Tales. I kept thinking about that Hummer commercial (I hate Hummers!) where G-locks steals Baby Bear’s H3. I presumed Papa had an H1 (like Schwarzenegger) and Mama had the H2. So, if Baby Bear had an H3, it follows that he was old enough to drive, and if so, he was also old enough (in human years) to have those intimate urges. (I once asked a guy who was driving an H2 how many gallons to the mile he got. He said about 12, which shows either he wasn’t listening, or he’s heard it so many times that he just automatically answers with miles per gallon.
Once I got going, it was too good to stop. I had to keep writing.
Not really sure where all that came from, haha! I didn’t know I had any sort of abiding interest there.
:shrugs: Ya never know.
I looked: I don’t have any Malt-o-Meal in the house. Next trip to the store.
Isn’t three an auspicious number? (I don’t know yet myself, only what I see here–I’m still waiting to find “Inheritor” and I’m going in order.)
Malt-o-meal IS porridge! So are oatmeal, grits, corn mush, cream of wheat, cream of rice, polenta, and the infamous split pease cooked down to a mush. Berries are a nice addition, so are bananas.
I think in the original Grimm’s version, the bears tore her to pieces, but I’d have to unbury my complete tales and look that up.
As I understand there, there might still be an Earth-mass planet in the Goldilocks zone of Tau Ceti. They were able to detect Tau Ceti d, orbiting at four Earth masses just inside the inner limit of the Goldilocks zone at 0.55 AU, and Tau Ceti e orbiting at six Earth masses on the outer fringe of the Goldilocks zone at ~1.35 AU. There could still easily be planets less massive than d and e orbiting in the 0.8 AU between the two planets, worlds that escaped detection simply because they aren’t massive enough to be picked up.
Perchance we might get a Pandora or Endor situation, where the habitable planet is a moon orbiting a gas giant. I wonder how livable Titan or Europa would have been, if Jupiter or Saturn had formed around the Goldilocks zone.
They wouldn’t have been liveable. Europa can retain its ices, and Titan its ices and its atmosphere, only because they are so distant from their local star. If Titan was in orbit around Jupiter, it would overheat and end up looking like atmosphere-less Callisto.
Could the discovered worlds have habitable moons? They could certainly have moons, but as I noted Tau Ceti d is a bit too close to its sun while Tau Ceti receives less illumination than Mars.
And, for all we know, some of that detected ‘planetary weight’ is made up of moon(s)!
They’d have to be big moons, to make much difference. Our moon’s mass is 1/81 the Earth’s. And that’s closer than a lot of them. (Except Charon which is something like 1/9 of Pluto’s mass.)
It’s always possible there’s something different out there in the universe. Two identically-massed planets orbiting each other, for instance. (Tide problems? Put them something like a million miles apart. Would that make their orbit unstable?) Or planet wider, but much less dense than the Earth: That’d lessen its gravitational pull. (But not so much its escape velocity, and I suspect its atmosphere would be troublesomely thick.)
I’d also say that we still don’t really know what it would take to harbor natural life, or originate it, *or* be suitable for human colonization. It occurs to me that gravity, in itself, might not be a big deal for aquatic creatures, especially small ones. It’d be a huge deal for us. Special technologies might make a high-gravity colony possible: But they’d have to be economical and reliable to make it viable, and *extremely* so to make it anything like living on Earth.
Speaking of gravity, a 4th grader in my community is doing a science fair project on obesity in cats she’s calling “Garfield Syndrome.” I know many people here have cats. It would be great if you could help her out by filling out her survey. It will only take a few minutes. This is the website for her project.
http://www.kaeuper.com/GarfieldSyndrome/
Catch Discovery Channel’s How the Universe Works/Planets from Hell…forget everything you ever thought was a no-no: planets around multiple suns, multimass Jupiters closer to their suns than Mercury is to ours; planets with incredible winds, a planet around a neutron star…Our Earth is so nicely behaved the last 180,000 years, give or take the Toba eruption.
If it turns out that Titan or Europa (or Io?) have any sort of life, however primitive or advanced, it would be a game-changer. Surely interesting, in that the possibility or likelihood means life elsewhere is more likely.
A “habitable moon,” like Endor or Yavin in the Star Wars universe, seems like a reasonable enough possibility. Presumably the gas giant the moon orbits would need to be very large and closer to its star, and the habitable moon would need to fit certain parameters to maintain an Earth-like environment (gravity, atmosphere, temperature range, etc.).
Two planets within the Goldilocks Zone in a system… reminiscent of how we used to think Mars or Venus might be habitable.
Anybody want a good deal on a flatcat? Or a bicycle? 😉 (At least they didn’t try to sell their twin or their grandmother or their kid brother…. Not that we know of, anyway. LOL.)
Presumably the gas giant the moon orbits would need to be very large and closer to its star, and the habitable moon would need to fit certain parameters to maintain an Earth-like environment (gravity, atmosphere, temperature range, etc.).
There’s more to it than that. 😉 One of Jupiter’s moons creates a ring of sulfur atoms in its orbit. (Io?) A Jovian-type planet has its own local environment affecting its moons, e.g. a magnetosphere. It’s not clear exactly whether that would be habitable.
The early planet-finding techniques were a ‘coarse gravel’ sieve that turned up Jupiters or larger, but now that we’ve got Kepler, detecting pieces of sand like Earth-sized planets is possible. I tend to think the orbital mechanics that produced Sol Sytem did not defy the laws of physics, to apply Occam’s Razor (take the simplest assumption, among the competing ideas)—I think what shook out of Sol’s original cloud of matter is pretty average, given a second-generation star (meaning it had a predecessor to create iron and spit it into the cloud)…
So the finer our screen gets, I think the better we will see the sand and grit of a lot of other
systems, and not just the major rocks.
We started by concentrating on those stars that have notable fluctuations, ie, big enough to see—and these systems, with gravity-hogs like mega-Jupiters running close to the star, may not be the friendliest to little chaff like us. But stars that aren’t quite so obvious as having planets may turn out to be more sunlike.
The one sure thing we’ve learned is that all the pontifications about where you can and can’t have planets are tossed into a cocked hat: nature is wonderful about saying, “It’s not as simple as you think: go think again.”
I tend to think the orbital mechanics that produced Sol Sytem did not defy the laws of physics
Certainly not! But as you say, “Go think again.” I’ve seen analyses that the existing structure required another planet that got tossed out, and the readjustments were what gave us what we have now. It’s hard to explain Neptune’s orbit without something like that having happened.
It’s suggested in the source of How the Universe Works (I haven’t actually read the mechanics) that Jupiter and Saturn slingshotted each other after a series of orbital coincidences and their movement destabilized Neptune and Uranus, which were flung outward, but decelerated when they ran into the debris field out in the cold beyond, thus producing the Late Heavy Bombardment that cratered the inner planets and moons(those with surfaces that wouldn’t just swallow the impactors without much fuss.) We exist in a stable period in the solar system, but their sources warn that these periods of orbital stability and dullness are alternate with the alternative. I love space billiards.
In the early solar system, planets that took a hit:
Mercury—possible hit by a large impactor that sheared off most of its crust: it’s essential a large iron ball bearing with a thin coating of dirt.
Venus—we’re not sure.
Earth—hit by a Mars-sized planet, Theia, remelted, scrambled two cores into one, cast off a lot of material including core fragments, and produced the moon, which is slowly getting away from us.
Mars—hit by a comet or planetoid large enough to strip off most of the crust much of the northern hemisphere. Its moons are captured asteroids and one is slowly getting closer to it.
Jupiter—hit by pieces of Shoemacher-Levy 9, while we watched, in a series of explosions larger than the Earth itself. Its moons show numerous impacts.
Saturn, Uranus, Neptune, too far to get specific, but Uranus orbits at such a tilt it is theorized it was hit bigtime by something. Their moons are likewise thoroughly peppered by bombardments.
it’s a messy environment out there!
It’s a messy environment in here! Just ask the Russians. 🙂 🙂 🙂
Apropos Downbelow, just stumbled over this one on the geek & sundry Youtube channel: This month’s Sword and Laser book club pick is Downbelow Station: http://www.youtube.com/watch?v=U4fkQ_l7rjI. Cherryh section starts at around 02:15.
Unfortunately I find the whole presentation somewhat annoying, but hey, I already have all the Alliance books 🙂
Thanks for the post, I’ve read Downbelow a couple times but it was interesting seeing the youtube discussion on it.
Thanks!
CJ any chance of another Union-Alliance novel?
A Regenesis follower is highly possible: my publisher wants it. Others re the ships are not impossible.
Mar. 12, 2013 — The number of potentially habitable planets is greater than previously thought, according to a new analysis by a Penn State researcher, and some of those planets are likely lurking around nearby stars.
“We now estimate that if we were to look at 10 of the nearest small stars we would find about four potentially habitable planets, give or take,” said Ravi Kopparapu, a post-doctoral researcher in geosciences. “That is a conservative estimate,” he added. “There could be more.”
Kopparapu detailed his findings in a paper accepted for publication in Astrophysical Journal Letters.
Penn State (2013, March 12). Earth-sized planets in habitable zones are more common than previously thought. ScienceDaily. Retrieved March 17, 2013, from http://www.sciencedaily.com/releases/2013/03/130312152047.htm