So yeah, the only weird stuff you’d notice would be collisions with interstellar stuff with a different relative velocity to yours. Like neutrinos (there’s no charge for them!), solar wind particles, teapots, etc. Except for neutrinos, of course. Confused? So am I…

astronaut2k05

The universe is a big place, almost infinite

What does “almost infinite” mean, please?

I was under the impression that “infinite” was a Boolean operator.

The chances of intelligent life existing must be more than 1:infinity-1

Why must they?

Earth is not the only place inhabited by intelligent life.

There is no evidence for this, AFAICT.

Humans do not have the sole claim to “intelligence”.

I have yet to see it proved conclusively that humans, on average, have any claim to intelligence.

However, is there the opposite of speed or velocity in mathematics?

Speed is a scalar quantity so it has no opposite.

Velocity, however, is a vector so it has a direction as well as a magnitude. The opposite of velocity (negative velocity) is, prosaically, speed in the opposite direction.

@Nigel #86, this has been a pet peeve of mine too.

Solidarity, sibling!

Complete layperson here- what does a 28 day orbit do to its atmosphere? i.e. does it get blown off at that speed? Compressed in the direction of it’s orbit?

Since the planet is moving through the vacuum of space, nothing happens to the atmosphere as a result of the panet’s orbital velocity.

However, a planet’s atmosphere will be affected to some extent by the solar wind from the parent star. If the planet has a magnetic field, then its atmosphere will be mostly unaffected by this. If the planet has no magnetic field (or a trivially weak field), then a strong solar wind could eventually strip the lighter elements from the atmosphere. This is an oversimplification, but I hope it gets the basic idea across.

. . . this has lead astronomers . . .

And who says they are metal-poor, if the astronomers are made of lead?

I’m sorry to say you have triggered a new pet bugbear of mine, that I have been noticing increasingly over the last two years (roughly). Lots of people do it, so please don’t feel like I’m having a go at you specifically, but I can remain silent on the issue no longer.

Please please please take note:

The verb to lead (pr “leed”) has the past participle led. Note the absence of the “a” in the past participle.

Lead pronounced “led” is the chemical element Pb.

Lead (Pb) / led is an example of a homophone, where two (or more) words with different meanings have the same pronunciation but different spellings.

English is rife with homophones (I believe there are hundreds of examples). With these words, there are only two clues as to which version of the word you mean to use – the spelling and the context. By neglecting the alteration of spelling, you force your reader to deduce your meaning from context alone. This interrupts the flow of the text and coincidentally causes my inner grammar nazi to explode in outrage.

I really think that within a millennium or so after we begin colonizing the rest of this solar system, someone will start that trek,,,even if it takes 10,000 years to get to the next system, that’s insignificant for a colony of several million people, whose colony IS their H.O.M.E.. The only use for planets in this scenario is for resources, not to live on,,,and in a few million years, we’d own the galaxy,,,or at least their Oort clouds,,,

Gary 7

“Which – don’t forget – includes two other suns Gliese 667 A & B – which may or may not be easily split and would certainly at least be exceedingly bright stars – think much brighter than Venus probably more like crescent or gibbeous moonlight but perhaps from point sources!”

Precisely! I had those in mind when I made my own comment.:)

I also think that if there really were a way to beat the speed of light limitation that were not too prohibitively difficult or expensive, there would be a strong likelihood that the first sentient species in any given galaxy that discovers that secret would completely overrun and dominate that galaxy long before a second or subsequent species discovers that same secret. Thus the mere fact that alien sentients are not already here makes me very strongly suspect that either the speed of light limitation is insurmountable by any practical means, or that we are the first or only technologically adept species in our galaxy. Both could be true, of course, but I think it is more likely that only the first of those is true.

There are, however, at least a dozen more extant species that could be said to be “intelligent” in that they pass a basic self-awareness test (IIRC all of these are cetaceans, primates or corvidae).

To that list of clades we have to add elephantines and psittacines.

And possibly cephalopods, too.

Caveat : That we know of!
Although, most probably so, yes.

If there had been a species of troodontid, or gorgonopsid, that achieved technological intelligence of a rudimentary level, of, say, sharpened sticks and flaked rocks, or perhaps even all the way up to stone masonry, with an interval existence of even up to a million years (similar to how long human ancestors had such technology levels), before being snuffed by the great mass extinctions, the fossil record from that far back in time is sparse enough that just by bad luck alone, nothing at all of them could be preserved for us to find today.

I’d agree with all of that – except the “universe” word. Our cosmos is an awfully big place. What may be happening sentient technological species ~wise in the Andromeda galaxy, Messier 51 (the whirlpool galaxie), in Centaurus A or any of the billions of others galaxies is very much an open question.

Consider that if the rate of technological intelligence were 1 per galaxy per 10 000 years, this would result in literally quadrillions of such civilizations in lifespan of the universe, and billions if not trillions of them co-existing at the same time, but, unless one of them makes it to K3 status while another in a nearby galaxy is still extant, none of them will ever know that any of the others existed.

But, yeah, I suspect biological life may be common with intelligence much rarer and technological species rarest of all.

Well, since biological life is required for intelligence, and intelligence required for technology, this is a truism, and you’re probably justified in using a word stronger than “suspect” for all of it except the very first part. (ie Life >> Intelligence > Technology is pretty much a truism)

You forgot one: 15 Billion years is a long, long time. In 4 billion of those years our planet has managed to produce exactly one technological civilization that has been detectable to the universe at large for, at most, 100 years.

Caveat : That we know of!

Although, most probably so, yes.

There are, however, at least a dozen more extant species that could be said to be “intelligent” in that they pass a basic self-awareness test (IIRC all of these are cetaceans, primates or corvidae).

D’oh! That’ll teach me to skim read. I see you made the same point there I did in my response to you above. Oops. (Blushes.)

I’d hazard to posit that life is probably ubiquitous, higher lifeforms fairly common and “intelligence” to not be particularly rare. But technological civilizations are statistically rare enough that we may well be the only such in the universe during this tiny slice of time in which we are just that.

I’d agree with all of that – except the “universe” word. Our cosmos is an awfully big place. What may be happening sentient technological species ~wise in the Andromeda galaxy, Messier 51 (the whirlpool galaxie), in Centaurus A or any of the billions of others galaxies is very much an open question.

But, yeah, I suspect biological life may be common with intelligence much rarer and technological species rarest of all. Hard to draw any firm conclusion from a dataset of one living planet mind you. But going on all of prehistory before we developed history I’d say that’s the most likely reality.

*****

“Cosmology also tells us that there are perhaps 100 billion galaxies in the universe and that each contains roughly 100 billion stars. By a curious co-incidence, 100 billion is also the approximate number of cells in a human brain.”
- Page 237, ‘StarGazer’, Dr Fred Watson, Allen & Unwin, 2004.

Suppose, on the other hand, that it is actually two earthlike planets orbiting a common center of gravity which is, in turn, orbiting the star. I know this is extremely unlikely, but is there any way of ruling out that possibility, and how would that effect the habitability of those planets?

I like that hypothesis! I think its unlikely but I’d love to find it was correct!

They would probably both still have a permanent nightside, illuminated, if at all, only by the sunlight reflected from the surface of the other planet (and, of course, by any other astronomical objects visible in their night skies).

Which – don’t forget – includes two other suns Gliese 667 A & B – which may or may not be easily split and would certainly at least be exceedingly bright stars – think much brighter than Venus probably more like crescent or gibbeous moonlight but perhaps from point sources!

@64. Special One – February 8th, 2012 at 3:05 pm :

Earth is not the only place inhabited by intelligent life.

Well it is that we know of for sure! It probably isn’t in reality though.

Humans do not have the sole claim to “intelligence”.

Yeah, my cat tells me that much!

Depends how you define intelligence but many earthly animals arguably are from chimps and dolphins to Jack-Russell X Fox terriers and elephants.

*****
Incidentally, re-reading the first link properly – and the links at the base of that news release I see that Gliese 667 itself is faintly visible in very dark skies for those with good eyesight – apparent magnitude 5.8 in Scorpius conveniently located between the sting and the Antares trio. (Finder chart linked to my name via the original press release.) So, there’s a chance, we can actually see this star with unaided eyes or binocs ourselves which, well, makes me really happy anyhow.

There have been suggestions that some carbon rich dust disks could form carbon planets with asphelt tarry surfaces, layers of diamond and silicon carbide and carbon monoxide skies. Read an article in Astronomy magazine ’bout that years ago.

Citations ~wise, I’m not 100 sure if there are any set rules here. So I’ll just say what I personally like to do for that :

When quoting I like to use @[number of comment being responded to]Personsname – sometimes time if the post numbers may be changing due to moderation, then blockquote (indented paragraph ) for the quote.

For the Opening Post by the blog /article writer I’ll usually just blockquote (indent) the quote. For material quoted from earlier comments I’ll use italics but material from off the thread I’ll usually leave plain text. Plus note the source usually in the author, date university standard eg. (Source : OneOfNone comment 73 -GJ 667C exoplanet thread, 2012 Feb. 9th -6.55 am) with links when I’m quoting online material and pages numbers, book titles /authors and sometimes publishers plus year of publication when quoting printed texts. Titles get italicised usually – the convention I’ve grown up with. Being a lousy typer I stuff things up on occassion but I do try to give credit where its due and allow others to know where my information is coming from so theycan check it themselves if so inclined. Thus the more specific the source info the more helpful it will be for that end.

But that’s just me & I’m probably a little OTT & quirky in this regard compared to most here.

@14. ctj : “Messier Tidy Upper, remember that to astronomers, a “metal” is anything other than H or He.”

Yep, indeed. I’m sure that must drive the chemists crazy!

Maybe
But to make real rocks, you need real metal.
Or at least half that. For ordinary sand, you need silicon and oxygen.

It is difficult to make any rock/rigid stuff, which is entirely from the upper right of the periodic table. Diamonds may count, or ammonium nitrate.

PS: are there any instructions on how to make correct citation in the comments?