Some scientist think globular clusters aren't good places to look for neighbors.Others took a fresh look at the data, crunched numbers, and pointed out that parts of globular clusters might be better spots for interstellar civilizations than the boonies where we live.
Meanwhile, someone with a lot more money than I'll ever see decided to spend some of it on a systematic search for extraterrestrial intelligence.
Flying Chicken Incubators, Invaders, and All That
I read speculative fiction back when it was called fantasy and science fiction, watched The Invaders, and enjoyed Star Trek when it was new. (September 4, 2015; September 7, 2014)But — do I "believe in" space aliens?
No, not in the Close Encounters of the Third Kind sense.
My guess is that most folks say "UFO" these days, when talking about visits with space aliens.
The term "flying saucer" goes back to around 1947, when Kenneth Arnold said he saw nine UFOs flying near Mount Rainier.
Seeing flying saucers, having conversations with or being abducted by, aliens — interstellar pregnancy test optional — was all the rage for the next decade or so.1
Small wonder that I run into folks who dismiss the notion of extraterrestrial intelligence as nonsense: if they're feeling charitable.
Do I "believe" we're alone in the universe?
That depends on what you mean by "alone:" and "universe," for that matter.
SETI
(From SETI@Home BOINC Client software, via Wikimedia Commons, used w/o permission.)
(Screen shot of SETI@Home screensaver.)
Depending on context, SETI means Search for Extraterrestrial Intelligence; SETI Institute, an astronomical research organization; or SETI@home, software using the BOINC platform.
Seti, or Sethi, or Sethos, if you like ancient Greek, was a not-uncommon name a few millennia back. I hardly ever hear folks talking about Seti the Viceroy of Kush; commander Seti, grandfather of Seti I; Seti II; or Seti-Merenptah; now, though: and that's another topic.
Where was I? Alien abductions, old television series, public figures of Egypt's 19th dynasty. Right.
I was running SETI@home on my desktop computer, some years back. The software's demands on my system resources were minimal, and I liked the idea of helping folks search through digital haystacks in search of a needle that might not be there.
SETI@home apparently didn't find space aliens, but did identify a few spots in Earth's sky with mildly anomalous electromagnetic activity. My guess is that they're natural phenomena, not neighbors: but we'll learn something by reviewing the data and making new observations.
Maybe. It's also possible that SETI@home's data and analysis will get lost or ignored. I hope not: that was a lot of data.
Although I recognize that some organizations use SETI as part of their outfit's name, I use the term generically, meaning humanity's recent search for neighbors.
I've known a few folks who apparently really "believed in" space aliens of the 'take me to your leader' or 'we have come to lead mankind to a groovier tomorrow' variety.
I've known others who share my belief — that the universe is real, follows knowable laws, and that we may or may not share it with other creatures like us. Well, more-or-less like us.
About the universe operating according to logical, knowable, physical laws: as a Catholic, I must believe that. (Catechism of the Catholic Church, 299)
Ignoring God's wonder-filled creation is most emphatically not part of my faith. (November 6, 2015; March 29, 2015)
Alone: Or Not
I am firmly convinced that in all the vast expanse of this universe, through all the billions of years which have elapsed since it began, and until it finally ends — humanity is alone, that nobody else lives and looks at the stars, and wonders if they are alone.Or we have neighbors.
Right now, we don't know.
Either way, I figure it's up to God whether or not we have company.
As far as I know, the Catholic Church hasn't made an official statement on this particular topic. That's hardly surprising, since we've got very little data to work with.
Besides, the general principle was addressed back in 1277, when some Aristotle fanboys said that there couldn't be any other worlds — because Aristotle said so.
Some of the 219 Propositions of 1277 have since been rescinded, but not the basic principle of 27/219: God's God, Aristotle's not. (October 23, 2015; May 8, 2015)
Getting back to those earnest folks who look to the stars in hopes that space-alien emissaries of niceness will come to solve all our problems — I think, and hope, that they're sincere. I'm also quite sure that they're wrong.
I implied earlier that I'd talk about what I mean by "alone" and "universe," and this looks like a good spot to blather on about my take on what's real and what's not.
Ladders, Angels, and (Maybe) a Multiverse
I've talked about the Scala Natura, Ladder of Nature/Creation, before. (August 2, 2015)We've learned a bit in the two dozen centuries since Plato and Aristotle studied the nature of reality.
When the 45th century rolls by, I'm quite sure we'll have filled in some of the gaps in today's knowledge, discovered new vistas that we hadn't known about before, and that's yet another topic.
Skipping past Plato's forms, Aristotle's taxonomy, and Medieval Neoplatonism — we're learning that living creatures don't divide neatly into "plants" and "animals," for example — I think the the scala naturae, or ladder of nature, is still an adequate illustration of some very basic ideas.
Humans are living creatures with a material body: the sort we call animals. But we're not just animals. We can reason and have free will. We can decide what we do or do not do. (Genesis 1:27; Catechism, 1951, 1700-1706, 1730)
It's being rational creatures that makes us "in the image of God." (Catechism, 1730)
We may or may not learn that we share this universe with other self-willed creatures with material bodies of some sort.
On the other hand, we've known about the folks without bodies for a very long time.
Angels, like us, are intelligent and have/had free will; but they don't have bodies. They're pure spirit, not material at all. (Catechism, 328-330)
Some angels work for God, others decided to do their own thing, that lot is not safe to be around, and that's yet again another topic. Topics. (Catechism, 391-395, 409, 414, 2851-2852)
When I write about neighbors in the universe, I'm talking about folks who are self-willed creatures with a physical form.
Some of what we're learning about quantum mechanics make more sense if we assume that we're not in the only space-time continuum, and that's still another topic. (September 26, 2014)
Assumptions
Efforts at finding or contacting extraterrestrial intelligence make an assumption which I think is dubious, at best: that our non-human neighbors are pretty much just like us.If non-human people live on another world, my guess is that they're not human: at all.
That, I think, would be a more sensible explanation than the conventionally pessimistic response to the Fermi paradox: that civilizations go into self-destruct mode as soon as they develop the sort of tech we did about fifty years ago.
I don't see why every intelligent species must be as irrepressibly chatty as we are. Then there's the assumption that everyone, everywhere, uses modulated electromagnetic signals for long-distance communication.
I've discussed Oldowan tools, slit gongs, Klemperer rosettes, and H. P. Lovecraft, before. (July 24, 2015; June 27, 2014)
1. Globular Clusters and SETI
(From Science Photo Library, via BBC News, used w/o permission.)
("Plenty of neighbours: Might clusters like this be the place to search for alien civilisations?"
(BBC News))
"Star clumps harbour 'sweet spot' in search for alien life"First, a quick review.
Jonathan Webb, BBC News (January 7, 2016)
"Ancient, tightly packed clumps of stars found at the fringe of the Milky Way are a good bet in the search for extra terrestrial intelligence (Seti), research suggests.
"Because of their abundance of stars, these 'globular clusters' were an early favourite in the Seti field.
"But recent efforts to scour the sky for planets orbiting alien stars have had little success within star clusters.
"Now, two astronomers say there is good reason to keep up the search.
"Rosanne Di Stefano from the Harvard-Smithsonian Center for Astrophysics, US, and Alak Ray from the Tata Institute of Fundamental Research in India, have described what they call the 'globular cluster opportunity'...."
This universe began 13,799,000,000 years ago, give or take 21,000,000. Stars started forming somewhere between 150,000 and 1,000,000,000 years later. Many or most of those stars are no longer around.
The larger ones became supernovae. Others eventually became red giants. These stars produced elements heavier than hydrogen and helium. Red giants release these elements gradually, Supernovae dump their contributions into the cosmos rather abruptly.
Either way, clouds of gas and dust — including heavier elements — collapsed to form new stars: including our sun. The Solar System is about 4,600,000,000 years old now.
Life appeared on Earth at least 3,500,000,000 years back, folks were making stone tools 3,400,000 years before Darwin published "Origin of Species" — that was 156 years ago — and I've been over this before. (August 14, 2015; May 29, 2015; July 15, 2014)
'Life as we know it' depends on water, which is made of hydrogen and oxygen; and requires a wide variety of heavier elements.
Globular clusters, according to that BBC News article, are about 10,000,000,000 years old on average. Their stars generally don't have as many heavier elements as ours: but we're leaning that such stars can have rocky planets like Earth orbiting them.
Here's where it gets interesting.
Speculation
(From Science Photo Library, via BBC News, used w/o permission.)
("Back in 1974, globular cluster M13 was the target for the first deliberate radio transmission into outer space"2
(BBC News))
We're learning that a planet like Earth could be in a stable orbit in the habitable zone of a small, stable, and very old, star in a globular cluster.
If life started on such a planet, and folks more-or-less like us showed up about three and a half billion years later, like we did — that's a lot of "ifs."
But if all that happened, there could be folks living on such a world: whose ancestors started sending probes into the universe before our sun began shining.
Such a world almost certainly wouldn't exist in the most densely-packed parts of a globular cluster. Tidal/gravitational forces from passing stars would disrupt its orbit: probably. The good news is that globular clusters thin out toward the edges.
"...there is a region within these clusters, Dr Di Stefano said, where the stars are not so tightly packed that huddled, small, rocky planets would be stripped from their stars - and yet they are still close enough together that an alien civilisation might manage the leap from one to another.The typical distance between stars in a globular cluster is around 1 light- year: that's just an average, though. (Wikipedia)
"Fun speculation
" 'In this large region... planetary systems can survive, and yet it's dense enough that it may facilitate interstellar travel.'
"In fact, she added, these planets - if they do exist - could last even longer than the current age of the Universe, leaving ample time for intelligence and interstellar ambition to flourish.
"Other researchers at the conference agreed that these were interesting observations, even if the notion of ancient, star-hopping civilisations was - of course - a provocative speculation...."
(, BBC News)
Let's say that folks whose home world orbits a star that's dimmer, cooler, and older, than ours — and is in the 'one light-year between stars' section of a globular cluster — got curious about their corner of the universe, and started sending probes out.
If they were as good at building robot spaceships as we were in 1977, they could launch something like Voyager 1. If they did, their probe could reach the closest star in a little over 2,250 years.
Outward Bound
(From Ames Research Center of the United States/NASA Photo ID: ACD97-0036-1, used w/o permission.)
Voyager 1 is currently outward bound, headed in the general direction of the constellation Camelopardalis. About 40,000 years from now, unless someone goes out to retrieve it, it'll be in the general vicinity of Gliese 445, some 17.6 light-years away.
We can't build probes that'll stay in good working order for 40,000 years, yet. But if we lived on that hypothetical planet, and knew that a probe could reach another star in a bit over two and a quarter millennia?
My guess is that some of us would be figuring out how to make a probe that would last that long.
Maybe someone already has: and has been working on 'next generation' technology since Earth's Hadean eon began.
More:
- NASA
- Advanced Propulsion and Power
- "Is Warp Drive Real?"
(March 10, 2015) [answer: not today] - Where are the Voyagers?
Voyager 1
- Tau Zero Foundation
Pioneering Interstellar Flight - Wikipedia
2. SETI, Breakthrough, and Assumptions
(From Wired, used w/o permission.)
"SETI Gets a $100 Million Gift"Breakthrough Listen is one of Yuri Milner's Breakthrough Initiatives, a systematic search for other people in the universe. Breakthrough Listen's goal is to check 1,000,000 stars for artificial radio or laser signals.
Danielle Venton, Science, Wired (December 21, 2015)
"This summer Russian tech billionaire Yuri Milner announced he’ll fund the most extensive sweep yet for radio signals from alien civilizations. The initiative, known as Breakthrough Listen will allow SETI scientists to buy thousands of observation hours annually at some of the worlds most powerful radio telescopes. The search will scan 10 times more sky than past scouting efforts and will listen in to a larger range...."
They may find something — or not. My guess is "not," for reasons I discussed last year. (July 24, 2015)
It's not that I think we're alone in the universe — or that we are, and are being ignored.
Basically, I'd be astonished, and pleasantly surprised, if we pick up signal from folks who are as chatty as we are — in the next decade — using communications tech that's almost identical to what we developed over the last few decades.
Scenarios like that are fine for space opera: but my guess is that we'll find that the universe is a whole lot more interesting than what we've seen in Star Trek.
As for whether or not Mr. Milner should be supporting this effort? I figure that it's his money: and I can think of much less-productive ways he could spend it. Besides, maybe Breakthrough Initiatives will hit the jackpot.
More, mostly why I won't tell God how to run the universe:
- "Enceladus and Kepler's Planets"
(December 18, 2015)
Particularly - "Organics on a Comet, and Earth's Early Magnetism"
(August 7, 2015)
Particularly - "Faith, Fear, and Flying Saucers"
(August 2, 2015)
Particularly - "Pluto's Unexpected Terrain; SETI, Radio, and Drums"
(July 24, 2015)
Particularly - "Life in the Universe, and Titan's Disappearing 'Island' "
(June 27, 2014)
Particularly
1 If even a fraction of the 'I met space aliens' tales were true, Earth would be — in my opinion — an unaccountably popular destination for profoundly bored aliens. I've opined seriously and otherwise, on life, the universe, and everything, in other blogs:
- Apathetic Lemming of the North
- "The Great Moon Hoax, Dihydrogen Monoxide, and a Rambling Lemming"
(July 18, 2014)
Particularly - " '...If There Were Intelligent Life Up There....' "
(November 22, 2012)
- "The Great Moon Hoax, Dihydrogen Monoxide, and a Rambling Lemming"
- Drifting at the Edge of Time and Space
- "NO! Don't Shoo... - - - GLIPNARF!!!!"
(January 16, 2014) - "The Aliens are Coming! The Aliens are Coming!"
(April 26, 2010) - "Interstellar Empires, Imagination, and an Occasionally-Sozzled Detective"
(March 12, 2010) - "Gods, Demons, and Used Spaceship Dealers"
(February 13, 2010)
- "NO! Don't Shoo... - - - GLIPNARF!!!!"
- Arecibo message
Wikipedia
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