- Meet 'Rosie:' A Fish With Legs, Sort of
- Weighs as Much as Earth: Not Particularly Earthlike Otherwise
- KOI-314c: a New Class of Planet
- Kepler-22b and Habitable Zones
- Darwin Glass and Trapped Organics
But first, why believing in space aliens isn't the same as thinking we may have neighbors.
Space Aliens, Elvis, and a Baleful Bat ChildI remember when Elvis sightings and space aliens were common front page news in supermarket checkout lines. Tabloid space aliens seemed obsessed with abducting Earthlings. The bat boy chronicles were a trifle more plausible: my opinion.
Taking my cue from tabloid headlines, most Americans have decided that Elvis really is dead. Dwindling numbers of diehard fans may be a contributing factor, and that's another topic.
Although the full-bore wacko adherent of a UFO religion is probably more common in fiction than in reality, imaginary space aliens have been as important in American culture as Elvis Presley.
Thinking of space aliens in cargo cult terms, expecting ambassadors from the stars to solve all our problems, doesn't make sense. It's as silly as expecting memory-sucking invaders from a dying star to give up after a single botched attack.
I don't "believe in" space aliens: either as secular saviors or as interstellar anti-nuke activists.
On the other hand, I think it's quite possible that we're not the only people in this universe.
Believing that a creature is divine is idolatry, and strictly against the rules. So is giving pleasure, wealth, or anything that's not God the attention that's intended for God. (Catechism of the Catholic Church, 2112-2114)
Wealth, health, and pleasure aren't bad by themselves, and that's another topic. (July 28, 2013; April 14, 2013; April 25, 2012)
Imagining that space aliens are gods is daft. Confusing them with angels is a bit of an improvement, but not much.
In a way, imagined space aliens fill a gap left when Anglo-American culture was purged of 'papist' beliefs, starting five centuries back. (September 22, 2011)
top dog is fairly new. I've described the ladder of creation before:
Space aliens, if they exist, would be on the same rung of the ladder as we are: below angels and above animals. I'd be astonished if they were exactly as smart as we are, with technology that's no more than a few millennia away from what we've got. I'll get back to that.
Angels are quite real, by the way, which isn't the same as having spirits and bodies: and that's another topic. (Catechism, 326-336) (February 22, 2012)
phlogiston was a good way to explain how fire works.
Today, quantum field entanglement is a good way to explain what sometimes happens to very small bits of reality.
Scientists learned that phlogiston didn't exist. Oddly enough, Unitarian and scientist Joseph Priestley, who supported the phlogiston theory, also discovered oxygen: which he called dephlogisticated air.
Priestley also thought that understanding the natural world would benefit people, and create Christ's kingdom on Earth.
Priestley was right about the first point: understanding the natural world. We've learned how to cure many diseases, eradicated smallpox, and produce enough food to feed everyone. Getting medical supplies and food to folks who need them is still a challenge.
The notion that science and technology will solve all our problems and bring about Christ's kingdom? That's daft. But the failure of Progress with a capital "P" doesn't mean that we should stop learning. (January 27, 2013; January 16, 2012)
Then as now, folks had trouble sorting out faith and science. Priestley's assumptions about Christianity didn't help.
Quantum field entanglement may be like phlogiston, or not. Either way, we'll discover why 'entangled' particles act the way they do by observing and analyzing this wonder-filled creation.
We'll learn whether or not there's life elsewhere in the universe the same way. This is a big cosmos, though, so it may take us quite a long time.
(From xkcd, used w/o permission.)
Again, I don't "believe in" space aliens: not in the UFO religion sense.
There's almost no evidence that people from other planets exist. One of the very few 'UFO' reports which I think could plausibly involve extraterrestrial intelligence involved damage to a patrol car in northwestern Minnesota.
I do not think this 1979 incident is proof that We Are Not Alone, but it could be the start of a good story. (Drifting at the Edge of Time and Space (January 16, 2014))
I'm quite certain that we either share this universe with other rational spirits whose design includes a physical body: or not. Right now, we simply do not know.
Claiming that other worlds cannot exist has been against the rules for Catholics since 1277. I think the same principle applies to saying that God couldn't make more than one set of people for this vast cosmos.
Earth's remarkable lack of space alien analogs to 50 gallon oil drums, six pack rings, and hamburger stands demands an explanation: assuming that we do have neighbors.
I think it's well to remember that this universe has been around for about 13,800,000,000 years, and life on Earth started at least 4,000,000,000 years back.
We've been using fire for at least 1,000,000 years; but started using radio only a bit over 100 years ago.
A thousand, or a million, years from now we may have developed something new.
If our neighbors got started a million years before we did: maybe radio communication is to them what flint knapping is to us. A million years sounds like a long time, but it's less than 1/4000th Earth's age. (Apathetic Lemming of the North (April 20, 2012; October 12, 2010))
If we do meet other people, it will be a wonderful opportunity to compare notes. We'd almost certainly be alike in some ways: and fascinatingly different in others.
Some differences might be in what senses we use to perceive the world. I'm not convinced that all people must be comparatively noisy, gregarious creatures like humans and most other primates.
Earth's last third of a billion years give, I think, a small sampling of how wonderfully varied life can be. There's a great deal for us to learn.
(From Kalliopi Monoyios, University of Chicago; via LiveScience; used w/o permission.)
"Scientists investigated fossils of a 375-million-year-old fish known as Tiktaalik roseae, discovered in 2004 in northern Canada's Ellesmere Island, finding they may have evolved rear legs before moving to land."
"Strange Ancient Fish Had Front And Back Legs"One of the critters in that picture reminds me of a cartoon character. I think it's the 'smile,' and the way Kalliopi Monoyios portrayed the eyes.
Charles Q. Choi, LiveScience (January 13, 2014)
"The closest known relative of the ancestors of limbed animals such as humans likely evolved the foundation for rear legs even before the move to land, researchers say. This ancestor may have even been able to walk underwater, they added.
"These findings reveal that a key step in the evolution of hind limbs happened in fish, challenging previous theories that such appendages evolved only after the move to land.
"Scientists investigated fossils of a 375-million-year-old fish known as Tiktaalik roseae, discovered in 2004 in northern Canada's Ellesmere Island. Possessing a broad flat head and sharp teeth, Tiktaalik resembled a cross between a fish and a crocodile, growing to a length of 9 feet (2.7 meters) as it hunted for prey in shallow freshwater...."
Tiktaalik roseae is a real animal, though, or was. That's a long name, so I'll call it Rosie from here on.
The University of Chicago's Neil Shubin and others studied Rosie fossils from Ellesmere Island.
That real estate is near Earth's north pole these days. It was near the equator 375,000,000 years back: along with the rest of the continent we call North America, a bit west of land that's now Kazakhstan and south China.
Earth's continents have moved quite a bit since then. As I've said before, change happens.
(From scotese.com, used w/o permission.)
(From Kevin Jiang, The University of Chicago; Model & cast made by Tyler Keillor; via LiveScience; used w/o permission.)
"The newly discovered pelvis of Tiktaalik roseae, pictured here between a life-sized reconstruction (left) and a cast of the skeleton (right), is described in Neil Shubin's inaugural article at PNAS with coauthors Ted Daeschler and Farish A. Jenkins, Jr.. Shubin was elected into the National Academy of Sciences in 2011."
"...This ancient creature was undoubtedly a fish, possessing gills, scales and fins. However, it also had features seen in modern tetrapods — four-limbed creatures like amphibians, reptiles, birds and mammals — such as a mobile neck and robust ribcage.Researchers had excavated blocks of rock with Rosie's rear limbs back in 2004. They'd focused their attention on other blocks first, since the 'rear blocks' didn't look like they contained much in the way of fossilized bone. Anyway, it takes years to extricate these fragile fossils.
"This extinct fish had large forefins and shoulders, elbows and partial wrists, enabling it to support itself on ground. This makes it the best-known example of an intermediate between finned animals and limbed animals marking the evolutionary leap from water to land for vertebrates, or creatures with backbones.
"Prior analyses of other fossils dating from the water-land transition found their back appendages were small and weak compared with their front appendages. This suggested the earliest ancestors of tetrapods perhaps had a 'front-wheel drive' form of locomotion that depended more on their front limbs, and that a 'four-wheel drive' form of locomotion with strong hips and back limbs only developed after tetrapods evolved...."
(Charles Q. Choi, LiveScience)
The University of Chicago's home page for Tiktaalik roseae calls the critter a fishapod: but I still like the "Rosie" moniker.
Maybe if more animals like the coelacanth and Rosie had been living near Europe and the Mediterranean, we'd have a name for creatures that aren't quite like other fish, and aren't amphibians, and that's another topic.
These Tiktaalik roseae fossils apparently don't include lungs, but Neil Shubin figures that Rosie could breathe air the way we do.
For one thing, those ribs wouldn't make much sense unless they wrapped around lungs. That makes sense to me. Some animals, like the kiwi and platypus, look odd to someone who grew up in central North America: but their weird appearance comes from practical design considerations.
More about Rosie:
(From C. Pulliam & D. Aguilar (CfA), via Harvard-Smithsonian Center for Astrophysics, used w/o permission.)
"KOI-314c, shown in this artist's conception, is the lightest planet to have both its mass and physical size measured. Surprisingly, although the planet weighs the same as Earth, it is 60 percent larger in diameter, meaning that it must have a very thick, gaseous atmosphere. It orbits a dim, red dwarf star (shown at left) about 200 light-years from Earth. KOI-314c interacts gravitationally with another planet, KOI-314b (shown in the background), causing transit timing variations that allow astronomers to measure the masses of both worlds. This serendipitous discovery resulted from analysis as part of the Hunt for Exomoons with Kepler (HEK) project."
"Newfound Planet is Earth-mass But Gassy""Life as we know it" may only exist on Earth. Life of any sort may be strictly limited to the nucleic acid/protein-in-water variety. Or we may discover that most life uses lipids in hydrogen. (October 19, 2012)
Harvard-Smithsonian Center for Astrophysics press release (January 6, 2014)
"An international team of astronomers has discovered the first Earth-mass planet that transits, or crosses in front of, its host star. KOI-314c is the lightest planet to have both its mass and physical size measured. Surprisingly, although the planet weighs the same as Earth, it is 60 percent larger in diameter, meaning that it must have a very thick, gaseous atmosphere.
" 'This planet might have the same mass as Earth, but it is certainly not Earth-like,' says David Kipping of the Harvard-Smithsonian Center for Astrophysics (CfA), lead author of the discovery. 'It proves that there is no clear dividing line between rocky worlds like Earth and fluffier planets like water worlds or gas giants.'...
"...The team gleaned the planet's characteristics using data from NASA's Kepler spacecraft. KOI-314c orbits a dim, red dwarf star located approximately 200 light-years away. It circles its star every 23 days. The team estimates its temperature to be 220 degrees Fahrenheit, too hot for life as we know it...."
Either way, I think KOI-314c shows that we've got a lot more to learn: and that planets about the size of Earth are fairly common. Eventually we may find one with a nitrogen-oxygen atmosphere, oceans, clouds: and life.
"...KOI-314c is only 30 percent denser than water. This suggests that the planet is enveloped by a significant atmosphere of hydrogen and helium hundreds of miles thick. It might have begun life as a mini-Neptune and lost some of its atmospheric gases over time, boiled off by the intense radiation of its star....Basically, the scientists were sorting through Kepler data for a wobbling planet. They were disappointed that KOI-314's data showed a second planet, not a moon: until they realized how little mass KOI-314c had.
"...To weigh KOI-314c, the team relied on a different technique known as transit timing variations (TTV). This method can only be used when more than one planet orbits a star. The two planets tug on each other, slightly changing the times that they transit their star...."
(Harvard-Smithsonian Center for Astrophysics press release)
Serendipity can be frustrating: but only when folks don't recognize it.
(From Geoff Marcy, via Space.com, used w/o permission.)
"Sub-Neptunian planets range in size from about 1.5 to 4 times the size of Earth and have a rocky core and puffy gaseous shell of varying thickness."
"Abundant 'Mini-Neptunes' Form New Class of Alien Planets"Back when I was in high school, some scientists figured that planets were very rare: that the Solar system might be one of a handful of planetary systems, or maybe unique. Others thought that when clouds of gas and dust condense into stars, planets were a common by-product.
Tanya Lewis, Space.com (January 6, 2014)
"There's a new kind of planet to add to Kepler's cornucopia of alien worlds, and you won't find it in Earth's own solar system.
"Ground-based follow-up observations of planets found by NASA's Kepler spacecraft reveal the masses and densities of 16 new planets ranging between one and four times the size of Earth. Many of the newfound orbs, described here today (Jan. 6) at a meeting of the American Astronomical Society, have a rocky core surrounded by a puffed-up envelope of gas, which scientists are calling 'sub-Neptunes' or 'mini-Neptunes.'
" 'This marvelous avalanche of information about the sub-Neptunian planets is telling us about their core-envelope structure, not unlike a peach with its pit and fruit,' study leader Geoff Marcy, a professor of astronomy at University of California, Berkeley, said in a statement...."
Better telescopes, more observations, and the number-crunching power of computers, showed that nebular hypothesis was a very good match with reality. We'd even spotted some 'stellar nurseries.' Evidence was piling up that planetary systems were fairly common.
Scientists were fairly confident that we'd eventually find planets circling other stars. The working assumption was that these planetary systems would be quite a bit like ours: planets in nearly-circular orbits; small, rocky ones near the star; big gassy ones farther out.
Then we started finding extrasolar planets. Some were in nearly-circular orbits, many weren't.
It's easier to find massive planets in tight orbits. They're the ones that make their stars wobble, or are likely to pass between their star and Earth. Scientists started calling them hot Jupiters, roaster planets, epistellar jovians, pegasids, or pegasean planets. I like "roaster planets" myself, but run into the term "hot Jupiters" more often.
Whatever they're called, these planets aren't like anything we'd seen before. Now that they've got more data to work with, scientist are tweaking the nebular hypothesis. The last I heard, there's more work to be done: but it still looks like clouds of gas and dust collapse into stars; quite often with a fascinating variety of planets.
"Kepler-22b: Facts About Exoplanet in Habitable Zone"The old Star Trek series introduced the phrase "class M planet," but the idea of alien worlds with climates like Earth's temperate zone is much older. We may eventually find a planet that's a near-twin to our home: but I suspect that we'll learn that life will thrive in places where we won't.
Elizabeth Howell, Space.com (December 31, 2013)
" Kepler-22b is a planet orbiting in the habitable zone of its sun-like star, Kepler-22, which is located roughly 600 light-years from Earth. With a radius of about 2.4 times that of Earth, astronomers noted after its discovery in 2011 that the planet's temperatures about the same. If the greenhouse effect is the same as well, scientists estimated its surface temperature is a life-friendly 72 degrees Fahrenheit (22 degrees Celsius).
"Although the planet is larger than Earth, astronomers hailed the discovery as a step to Kepler's goal of discovering Earth-size planets in the habitable zones of their respective stars.
" 'We're getting closer and closer to discovering the so-called "Goldilocks planet," ' Pete Worden, director of NASA's Ames Research Center in Moffett Field, Calif., said during the 2011 press conference announcing its discovery...."
One of the more intriguing speculations is that Earth may be about as small as a planet can be and still support life.
- "Earth May Not Be a 'Class M' Planet"
Apathetic Lemming of the North (December 5, 2009)
Life "as we know it" has endured Earth's periodic glacial epochs, asteroid impacts, and the occasional million-year-long volcanic eruptions. If life began somewhere else, my guess is that it will be just as durable.
We've learned that life as we know it needs liquid water, at least sporadically, chemicals like nitrogen, and an energy gradient. There's good reason to believe that microorganisms from Earth could survive on today's Mars. It's even possible that life started on the next planet out from the sun.
Of the thousand or so extrasolar planets we've spotted so far, a few might, maybe, be warm enough for our sort of life: but not too hot. Whether or not they've got the right chemical mix isn't known.
Here's a quick look at some of the more intriguing known planetary systems.
(from NASA Ames/JPL-Caltech, used w/o permission.)
(from NASA/JPL-Caltech/T. Pyle, used w/o permission.)
(from NASA/JPL-Caltech/T. Pyle, used w/o permission)
(NASA Ames/JPL-Caltech, used w/o permission.)
I think it's well to remember that the Kepler observatory's search was limited to a tiny slice of our galaxy. Mission planners had Kepler look down a particularly promising stretch of the Milky Way galaxy: but vast expanses remain.
(Painting by Jon Lomberg, Kepler mission diagram added by NASA, Smithsonian via Wikipedia, used w/o permission.)
(From K. Howard, via Astrobiology Magazine, used w/o permission.)
"Samples of Darwin glass range in size and color. White glass make up less than 3 percent of all finds."
"Organics Preserved in Ancient Meteorite-Formed Glass"Tasmania's Darwin Crater may be what's left of a meteor impact crater, but geologists apparently can't be positive about that. It's a circular depression with a lot of impact glass in the area, and something warped rock strata the way an impact would: so I'm guessing that a meteor hit there.
(December 16, 2013)
"Scientists have found organics from Earth's swamp trapped inside of glass created by a meteor impact almost a million years ago. The tiny pockets, only micrometers across, contain material such as cellulose and proteins. Though the impact glass was found on Earth, scientists say that similar samples could have been thrown into space by this or other blasts, allowing organics to be transported from one planet to another.
"Approximately 800,000 years ago, a rock 100 to 160 feet (30 to 50 meters) across crashed down in Western Tasmania, Australia. As it slammed into the Earth, temperatures exceeded 1,700 degrees Celsius (3,100 degrees Fahrenheit), melting rock and creating glass sphericals, as well as a quarter-mile wide hole known as the Darwin Crater...."
(From Google Maps, used w/o permission.)
Darwin Crater, Tasmania.
(From K. Howard, via Astrobiology Magazine, used w/o permission.)
"...'The reason the glass is so abundant seems likely to relate to the presence of volatiles like water at the surface when the impact occurred,' lead author Kieren Howard of the City University of New York told Astrobiology by email.What's in the Darwin glass is interesting, since it shows that organic stuff can get embedded in debris which in turn could be thrown out of Earth's atmosphere.
" 'A bit like when water from your spatula drips into a frying pan, having the right amount of water at the surface during impact may have increased the magnitude of the explosion, and the production and dispersal of the melt.'
"In Tasmania, the land was covered by swamps and rainforest, offering sufficient water to create the glass. According to the authors, glass from the Darwin Crater is the most abundant and widely dispersed impact glass on Earth, relative to the crater's size, with glass scattered across 150 square miles (400 square kilometers). In fact, the widespread glass led to the discovery of the crater, which is now filled with younger sediments, in 1972. ..."
If we find life on Mars, there's going to be a lively discussion over whether it started out on Mars, was carried there by an earlier space probe, or got carried from Earth inside something like this glass.
The idea that life spreads through the universe, carried on debris, is called panspermia. It's far from a crackpot notion. We've learned that an elephant grazing near an asteroid impact couldn't hitch a ride to Mars on debris thrown into space: but microbes might.
- "List of nearest terrestrial exoplanet candidates"
- The Extrasolar Planets Encyclopaedia
- SIMBAD Astronomical Database
CDS, Strasbourg, France
- NASA Exoplanet Archive
California Institute of Technology, NASA
- "Evidence That Organic Material Can Survive the Impact of a Meteorite"
SciTechDaily (November 13, 2013)
- "Dust and Fomalhaut: Learning that There's More to Learn"
(December 27, 2013)
- "The Eight-and-a-Half-Hour Year of Kepler 78b, and the Seven Worlds of KIC 11442793"
(November 1, 2013)
- "Kepler-69c and Habitable Zones; The Great Martian Land Rush"
(October 25, 2013)
- "Exoplanets and Extraterrestrial Life: The Search Continues"
(September 6, 2013)
- "The Three Super-Earths of Gliese 677C; and Unexpected Planets"
(June 28, 2013)
- "Dust and Fomalhaut: Learning that There's More to Learn"
- "Old Water, Older Fossils, and Extraterrestrial Etiquette"
(November 15, 2013)
- "Three Es: Exoplanets, Exobiology, and Evolution"
(October 4, 2013)
- "Time, the Universe, and Space Aliens"
Apathetic Lemming of the North (April 20, 2012)
- "Gods, Demons, and Used Spaceship Dealers"
Drifting at the Edge of Time and Space (February 13, 2010)
- " '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)
- "Old Water, Older Fossils, and Extraterrestrial Etiquette"