- Titan's 'Magic Island'
- Life: It's Complicated, and Complicating
- The Planet that 'Shouldn't Be There'
Star Trek, Scientists, and Catalogs of Known Worlds
(From European Southern Observatory (ESO)/L. Calçada, via Wikimedia Commons, used w/o permission.)
(An artist's impression shows a sunset on the super-Earth Gliese 667 Cc.)
As of June, 2014, scientists had cataloged 1,116 planetary systems other than our Solar system, and 1,797 planets circling other stars.
The good news is that we're learning a great deal more about our neighborhood. The exciting news is that we've learned that planetary systems aren't all pretty much like ours: and planets come in varieties that we hadn't expected.
We still haven't found a planet that's "class M" in the old Star Trek sense: but earlier this week scientists at the University of Puerto Rico, Arecibo, updated their list of exoplanets that might support life. On Wednesday, the list had 68 planets.
As folks at the University of Puerto Rico's Planetary Habitability Laboratory said, "the database is still under BETA and many changes and expansions are expected in the near future."
"Habitable" doesn't mean "inhabited." None of those planets may support life. But the search for life in the universe is no longer just an entertaining premise for speculative fiction:
- "Cosmological aspects of planetary habitability"
Yu. A. Shchekinov, Department of Space Physics, SFU, Rostov on Don, Russia; M. Safonova, J. Murthy, Indian Institute of Astrophysics, Bangalore, India (April 2, 2014)
(Via Cornell University Library (June 26, 2014)) - "Exomoon habitability constrained by illumination and tidal heating"
René Heller, Rory Barnes, Astrobiology (September 8, 2012)
(Via Cornell University Library (June 26, 2014)) - "Terrestrial, Habitable-Zone Exoplanet Frequency from Kepler"
Wesley A. Traub, Astrophysical Journal (September 21, 2011)
(Via Cornell University Library (June 26, 2014))
Alone in the Universe: Or Not
"Thar's only two possibilities: Thar is life out there in the universe which is smarter than we are, or we're the most intelligent life in the universe. Either way, it's a mighty sobering thought."I don't think that there is life on other planets. I don't think that there is not life elsewhere in the universe. Right now, we don't know.
(Porky Pine, in Walt Kelly's Pogo; via Wikiquote)
I'm not going to repeat the mistake made by some European scholars, around the time Thomas Aquinas was writing Summa Theologica. Debate about whether or not other worlds existed had gotten intense, with some scholars claiming that Earth had to be the only world in the universe: because Aristotle said so.
That's when the Catholic Church stepped in. Ever since 1277, claiming that we have to be standing on the only world has been against the rules. (February 23, 2014)
I think the same principle applies to whether or not we'll find microbes on other worlds: or intelligent life. Claiming that God couldn't get life started elsewhere, or that the Almighty is obliged to do so, is daft. God's God, we're not: and if we have neighbors, we'll find them. Eventually. Or maybe they'll find us.
Klaatu, Angels, and Getting a Grip
I don't 'believe in' space aliens. Not in the sense that I think people from other planets are gods.
If we have neighbors in this universe, they'll be like us: created beings with free will, and a body of some sort. They may be smarter than we are, or not; wiser, or not. But even if their intelligence and wisdom far exceeds ours — they'll be people, like us.
I've opined about groovy space aliens, memory-sucking invaders, and cargo cults, before. (April 11, 2014; February 8, 2013)
By the way, writing "people, like us" doesn't mean that I expect someone whose ancestors aren't human to look like Klaatu. I'd be astonished if people from other worlds look like us.
As a Catholic, I accept that we're created "in the image of God:" able to decide how we act: or not act. One of the big differences between us and angels is that we're designed with physical bodies, they're not, and that's another topic. (Genesis 1:26; Catechism of the Catholic Church, 328-349, 355-373)
Eldritch Horrors and SETI
I'll say this for the eldritch horrors of H. P. Lovecraft's Cthulhu mythos: the assorted Great Old Ones didn't look like actors in monster suits: and behave as if they are very sincerely not human. Not even close.
I've been — impressed — that most serious SETI (Search for ExtraTerrestrial Intelligence) efforts seem to make two assumptions.
Listening for radio or other artificial electromagnetic signals is reasonable: provided that our neighbors, if any, have very nearly the same technology we do; and that people who aren't human will be as chatty as we are.
Maybe, a million years from now, our descendants will still be using modulated electromagnetic waves or electrical impulses to communicate over long distances.
Maybe the only possible form that intelligence can take in this universe develops from tree-dwelling social critters with a penchant for making a great deal of noise.
Or maybe not. I'm guessing "not:"
- "Seriously Searching for Life in the Universe"
(February 8, 2013)
Particularly - " 'All We Want is Peace and Quiet' - Another Look at the Mind of the Alien"
Drifting at the Edge of Time and Space (December 9, 2009)
Living with Reality, Finding "Wonderful Things"
I don't agree with Lovecraft's view of reality, as reflected in his Cthulhu stories: but I sympathize with him, a bit.
Living from 1890 to 1937, Lovecraft experienced one of Western civilization's less tranquil eras: including the Titanic's truncated voyage, Modern art, and a global war. Combined with a string of personal crises, I can see how he might have imagined that the universe was at best indifferent: if not malevolent.
I don't think that we're in a hopeless situation, with ignorance as our best defense against cosmic horrors. That's partly because I've lived through another intriguingly hectic era, decided that suicide wasn't a reasonable option, and that's yet another topic. Topics. (January 8, 2012; January 28, 2009)
I do think that Lovecraft deserves a great deal of credit for realizing that extraterrestrial, non-human, intelligence is likely to be — non-human.
We're learning that critters like octopuses and squids are smart: but not like their vertebrate analogues. No big surprise there, since cephalopod brains aren't wired like ours, and that's still another topic. Then there's the surprisingly difficult challenge of defining just what life is, in the biological sense, and that's a topic for another post.
If catalogs of extrasolar planets and the ongoing search for life in the universe seem out of place in a 'religious' blog: you're probably new here.
Like I've said before, my faith doesn't depend on trying to keep up with what we're learning about this wonder-filled universe: but it's not threatened by knowledge.
"...methodical research in all branches of knowledge, provided it is carried out in a truly scientific manner and does not override moral laws, can never conflict with the faith, because the things of the world and the things of faith derive from the same God...."What we learn over the next decade, century, and millennium, will almost certainly upset some folks. People are like that: but not all people.
(Catechism, 159; emphasis mine)
I'm pretty sure that those of us who want to know what's over the horizon will keep looking: and finding "wonderful things."
1. Titan's 'Magic Island'
(From BBC News, used w/o permission.)
"The bright feature was spotted in images from July last year, but a few days later it had vanished"
"Titan: Clue to 'Magic Island' mystery on Saturn moon"The odds are pretty good that the 'magic island' isn't: an island, that is, or magic. As one of the researchers said, "'magic island' is a colloquial term that we use within the team to refer to this. But we don't actually think it's an island".... (co-author Jason Hofgartner, quoted by BBC News)
Paul Rincon, BBC News (June 22, 2014)
"Scientists have outlined their best explanations for a mysterious feature dubbed the "magic island", which has been spotted on Saturn's moon Titan.
The Cassini spacecraft captured the "island" during a flyby, but it had vanished by the time of the next pass.
The bright splodge is seen in Ligeia Mare, one of the seas of methane and ethane found at Titan's north pole.
Icebergs, waves and gas bubbling up from the sea bed are all possibilities, the scientists say.
The study by an international team has been published in the journal Nature Geoscience...."
Saturn's largest moon, Titan, is remarkably like Earth: sort of. Titan's mountains are made of ice, not rock; the sea is methane and ethane, not water; the rain is mostly methane; but Titan's wind, rain, seasons, and geology, look a great deal like Earth's.
The 'magic island' probably isn't a volcanic feature, since it appears and disappears so quickly. Scientists think it could be one of three or four things:
- Waves
- Rising bubbles
- Solids
- Floating
- Suspended
That's something I like about this universe: every time we learn something new, we learn that there's more to learn.
2. Life: It's Complicated, and Complicating
(From NASA, via astrobio.net, used w/o permission.)
"Earth's complex environment of 4,900 minerals likely came from the interactions of life with the surface and the atmosphere, Robert Hazen argues."
(astrobio.net)
"Why Complex Mineral Surfaces Could Be Indications Of Life"Diamond may have been the first mineral, formed in the early universe's supernovas. Metallic hydrogen isn't a mineral by the definition in this article, since it's metallicity has to do with pressure and electron shells, not crystalline structure, and that's yet again another topic. Topics.
Elizabeth Howell, astrobio.net (June 9,2014)
"Minerals are highly abundant on Earth and other planets. A 'mineral' is a solid substance that has a well defined atomic crystal structure and chemical composition. Ice, for example, is considered a mineral because it has a crystal structure (think of six-sided snowflakes) and the composition H2O. Rocks are naturally occurring solids that are composed of one or more minerals.
"At an April presentation for the Space Telescope Science Institute in Washington, D.C., Robert Hazen explained that as life evolved and grew more complex on Earth, so did the number of minerals. By extension, this could mean that a planet with more minerals would have life on it.
" 'The basic idea is if you look at Earth and other terrestrial planets, the near surface environment has changed dramatically through time — 4.5 billion years of history — and those planets manifested very dramatic changes in mineralogy,' said Hazen, an earth science professor at George Mason University in Washington, D.C.
"In simpler terms, that means that when a planet is formed, it would only have a few minerals and that over time, the presence of life would add to the mineral complexity. At first glance, this seems counter intuitive since minerals are lifeless. Hazen said mineral abundance increases because life alters the near-surface environment, forming complex chemical and physical micro-environments that change over time.
"What's more exciting is that scientists are just beginning to figure out the composition of planets outside of our solar system, which means that it could one day be possible to estimate if a planet has life based on the elements visible in telescopes...."
Diamond crystals may have helped jump-start life on Earth, which in turn has shaped the face of this planet: and I'm getting ahead of myself. (Apathetic Lemming of the North (July 28, 2008))
Getting back to the article, Earth had about 420 minerals in its early years. That's about what we've found on other rocky planets in the Solar system today: 300 for Mercury, 450 for Mars. Martian minerals including clays and hydroxides: most likely from glacial and volcanic events.
Earth's first life didn't have much to work with. Early microcritters had to eat rock and live off energy generated when rocks started weathering. Some of today's microbes oxidize iron in basalt, and that leads me to Earth's first environmental disaster.
The Great Dioxygen Disaster
2,500,000,000 years back, more or less, some microorganisms started making carbohydrate molecules like sugar, using sunlight, carbon dioxide, and water. Today's plants 'burn' those molecules, getting energy for their activities. Photosynthesis was good for the plants: but released a deadly gas into Earth's environment: dioxygen (O2).
Starting about 2,300,000,000 years ago, the Great Oxygenation Event killed off some anaerobic critters, forced others into oxygen-free niches, and set the stage for big critters that need dioxygen.
Oddly enough, some of these anaerobic critters are alive and well: and living inside the big oxygen-breathers.
As I write this, there's a lively colony of Bacteroides in me, helping me digest my food. Other anaerobic organisms, like Riftia pachyptila, live around hydrothermal vents. Closer to home, pork worms, another variety of anaerobic critter, encourage us to cook meat thoroughly. I've been over this before. (August 30, 2013)
Minerals, Mineraloids, and Life on Other Worlds
Earth started out with about 420 minerals. Four and a half billion years later, Mars has about 450 minerals: and Earth has 4,900 minerals, give or take. The researchers say that life is what made the difference: and they're probably right.
Some minerals, like coal, coral, and almost all limestone, wouldn't exist on Earth if life hadn't started here. On the other hand, these can be called mineraloids. That's because they don't have the crystalline structures that minerals do. Pearls get called mineraloids because organic substances connect their crystals; lapis lazuli is a mixture of minerals; and that's not quite another topic.
As we develop better tools for studying exoplanets, we'll know more about their surfaces: whether they've got sandy beaches, or salt deposits; and what gasses are in their atmospheres, those that have atmospheres, anyway.
3. The Planet that 'Shouldn't Be There'
(From The Gemini Observatory, used w/o permission.)
"GU Psc b is a gas giant so far from its host star that it can be seen without the aid of adaptive optics."
"Far Out: A Giant Exoplanet Where None has been seen before"Sheyna E. Gifford made a good point in this article's lead sentence. It's a lot easier to see something we expect, than notice something that's outside our experience: or that, like GU Piscium b (GU psc b), isn't where we thought it should be.
Sheyna E. Gifford, MD; atrobio.net (May 23, 2014)
"Humans have an eye for the familiar: for people, for civilizations, for planets and planetary systems that match what we have seen in the past. For this reason, as well as a few others, we rarely find something truly unique in the universe. When we do, it's often by happenstance.
"Finding a planet ten times the mass of Jupiter orbiting 40 times further out than Pluto was in some ways unexpected.
" 'It's not a type of exoplanet we had previously found and it's certainly not one that the theorists were expecting,' said paper co-author PhD student Marie-Eve Naud at the University of Montréal, 'especially not around low-mass stars like GU Psc (~30% the mass of the Sun).'..."
Up to now, scientists found most exoplanets where they 'should' be: fairly close to their stars. There've been exceptions, like rogue planets, that aren't particularly near any stars.
Exoplanets: Widening the Search
(From Shu et al. 1987, Courtesy of the James Webb Telescope and NASA; via astrobio.net; used w/o permission.)
"Timeline of where planets are expected to be found as their parent stars evolve when forming in a protoplanetary disk. The star GU Psc is part of the AB Doradus Moving Group, with an estimated age between 70-130 million years. As such, GU Psc b would be expected to be within 100 AU of GU Psc. Instead, it is 2000 AU away, suggesting a different formation mechanism"
"...Last June, Astrobio.net ran the surprising story of a planet 5-10 times the mass of Jupiter that formed 80 AU from its parent star. In yet another twist in the continuing saga of planetary treasure-hunting, researchers in Naud's group at the University of Montréal announced the discovery of a planet many times the mass of Jupiter at an incredible distance from its star: 2000 AU.Various scientists thought they had a pretty explanation for how our Solar system formed: in 1662, 1734, 1749, 1812, 1854, 1904, 1917, 1937, 1944, 1960, 1962, and 1954. By 1931 we had so many that someone spent time sorting them out into groups.
"This planet-GU Psc b-is so far from its star that it could be photographed without the aid of adaptive optics, appearing as an independent point of infrared light from its star GU Psc.
"Unlike GU Psc b, most of the 1700 plus exoplanets in NASA's current catalog have not been directly imaged, or photographed directly, in any wavelength. Their gravitational effects on their parent stars have been measured. Sometimes the dimming effect as they occlude the light from their parent stars have been recorded. Occasionally, existence of planet is inferred by the presence of a gap in dust disks rotating around a star...."
(Sheyna E. Gifford, MD; atrobio.net )
The nebular hypothesis is still a good match with what we've observed: for the most part. My guess is that it will need more tweaking: but that a couple centuries from now some version of Swedenborg's idea will still be a pretty good explanation for how many if not most planetary systems formed.
But I won't be surprised if scientists develop new mathematical models that explain some of the oddball systems we're finding.
Reaching Past the Low-Hanging Fruit
What I like most about GU Piscium b is that it 'shouldn't be there.' Protoplanetary disks exist: astronomers have studied them. The Orion nebula seems to be thick with the things.
Quite a few models we have today say that planets should not be found beyond 100 AU (astronomical units). But the models also also say that if a planet is withing about 5,000 AU of its star — it's likely to stay there for billions of years.
Discovering GU Piscium b doesn't disprove the nebular hypothesis, but it shows that we've got more to learn about how planetary systems form.
Quite a few recent searches for exoplanets looked mostly near very young stars. My guess is that researchers used the low-hanging fruit principle: looking where they figured most planets would be, and where planets would be comparatively easy to spot.
Marie-Eve Naud, a PhD student at the Université de Montréal in Quebec, and her team looked where planets probably weren't: but might be.
I'm impressed that astronomers found GU Piscium b only 14 years after Gemini Observatory, the twin observatories they used, saw first light. That suggests that scientists will find many more of these distant-orbiting worlds.
We may learn that GU Piscium b is a rogue planet that happens to be close to a star at the moment. If it's gravitationally attached to GU Piscium, its orbital period, or year, is 163,000 times what we have on Earth: so it'll probably be some time before astronomers have enough data about its position to show that it is, in fact, orbiting its star.
By then, we may have the option to travel the 155 light years that separate our Sol and GU Piscium, and that's — another topic.
More about GU Piscium b:
- "GU Piscium b"
Wikipedia - "Odd planet, so far from its star... " Joint press release from Université de Montréal, Observatoire du Mont-Mégantic, Centre for Research in Astrophysics of Québec, and Gemini Observatory (May 12, 2014)
- Life, the universe, and beyond
- "Habitable Worlds, Homer, and Haldane — or — Ganymede's Oceans, and Imagining Kepler-186f's Sunsets"
(May 9, 2014) - "Life in the Universe: Focusing the Search"
(April 18, 2014) - "Science, Faith, and Albertus Magnus"
(February 23, 2014)
Particularly - "Getting a Grip about Genesis, Gamma Ray Bursts, and (Maybe) a Multiverse"
(May 30, 2013) - "The Beauty of the Universe, God, and Respect"
(March 21, 2012)
- "Habitable Worlds, Homer, and Haldane — or — Ganymede's Oceans, and Imagining Kepler-186f's Sunsets"
- Neighbors, maybe
- "The Oldest Known Heart; Tweaking Bacteria; and Looking for Life in the Universe"
(April 11, 2014)
Particularly - "Strange New Worlds; Getting a Grip about Space Aliens; and a Fossil Fish"
(January 17, 2014)
Particularly - "Old Water, Older Fossils, and Extraterrestrial Etiquette"
(November 15, 2013)
Particularly - "Genesis, Optimus Prime, and Victorian America"
(April 10, 2012) - "Science isn't a Four-Letter Word"
(January 29, 2012)
Particularly
- "The Oldest Known Heart; Tweaking Bacteria; and Looking for Life in the Universe"
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