"Earth-Like," Minnesota, Finland, and Me
Say "Earth-like," and I'd probably think of a place with grass, trees, blue sky, and a lake nearby: sort of like northern Minnesota, or southeastern Finland. I've never been there, but maps show the same splattering of lakes that makes northern Minnesota popular with vacationers, resort owners, and mosquitoes.
Other than that, I don't have much of a connection with Finland, although quite a few Sámi live there. Which may or not have anything to do with me. Quite a few folks on the Norwegian side of my family are of medium height, have black hair, and (my opinion) not-quite-typically-European features.
That, and the slight epicanthic fold I see in the mirror, encourages speculation that my deep roots may be among the Sámi and/or Asian folks; as well as the Celts. None of which would surprise me at all. Folks move, either by choice or necessity. Sometimes we move a lot before settling again. And that's another topic. Topics.
Where was I? Minnesota, Finland, and ethnographic implications of peripatetic proclivities. Or maybe it's predilections. Yet more topics. Never mind.
It's a big universe, with billions of planets in this galaxy, and more galaxies than there are stars in our Milky Way. Maybe there's another planet that's such a close match to Earth's mass, age, chemical mix, temperature, and history that parts of it resemble biomes in today's North America and northwestern Eurasia. Then again, maybe not.
Kepler 78b
Folks at MIT recently found the most "Earth-like" planet yet. Kepler 78b is only 20 percent wider than Earth, and roughly 80 percent more massive than our home world. We still don't know exactly what elements it's made of, but it is about as dense as Earth: which means that it almost certainly is mostly rock and metal: just like Earth.Kepler 78b is close, by cosmic standards: light from its star arrives here after only 700 years. That's Earth years.
Nobody's likely to find life on Kepler 78b. Not the sort of life we're used to, anyway. The planet whips around its sun in about eight and a half hours. That's not a typo. Kepler 78b is very close to its star, and extremely hot. Surface temperatures might be as high as 3,000 degrees Kelvin, roughly 5,000 degrees Fahrenheit.
That makes the hellish climate of Venus seem positively inviting by comparison.
It looks like the planet could be called "Icarus:" Dimitar Sasselov (Harvard-Smithsonian Center for Astrophysics) says that Kepler 78b is too close to its sun. It will keep spiraling toward its sun until tidal forces tear it apart: about 3,000,000,000 years from now, maybe less.
If we want to try terraforming Kepler 78b, the first step will probably be towing it to a higher orbit. Yet again more topics.
Life, the Universe, and Getting a Grip
I've discussed - or beaten to death - why I don't have a problem with God working on a literally cosmic scale, and why thinking is okay.Basically, God created the universe, God doesn't lie, so studying the universe okay. (Catechism of the Catholic Church, 159)
Science and technology, studying the universe and learning how to use it, are part of being human. It's what we're designed to do. (Catechism, 2293)
We're also designed to use our power wisely, which is no guarantee that we will. No matter what new tech we develop, ethics still apply. (Catechism, 396-409, 2292-2295)
More of the same, and why Catholics aren't allowed to say that other worlds can't exist:
- "Science, Technology, and Being Human"
(January 27, 2013)
Particularly - "Science isn't a Four-Letter Word"
(January 29, 2012)
Particularly
1. Lava World
(David A. Aguilar (CfA), via Space.com, used w/o permission.)
"An artist's illustration of the strange Earth-like rocky planet Kepler-78b, which orbits a sun-like star 400 light-years from Earth. The planet is 20 percent wider and 80 percent more massive than Earth."
"Strange 'Lava World' Is Most Earthlike Alien Planet Yet"Kepler 78b is exciting because it's the closest match to Earth we've found so far; apart from being so hot. Finding it so early in our search implies that Earth-size planets are fairly common. Then again, maybe we just got lucky.
Mike Wall, space.com (October 30, 2013)
" A puzzling alien planet is the closest thing to an Earth twin in size and composition known beyond our solar system, though it's far too hot to support life, scientists say.
"The exoplanet Kepler-78b, whose supertight orbit baffles astronomers, is just 20 percent wider and about 80 percent more massive than Earth, with a density nearly identical to that of our planet, two research teams report in separate papers published online today (Oct. 30) in the journal Nature.
" 'This is the planet that, in many respects, is the most like Earth that's been discovered outside our solar system,' said Andrew Howard, of the University of Hawaii at Manoa's Institute for Astronomy and lead author of one of the studies. 'It has approximately the same size. It has the same density, which means it's made out of the same stuff as Earth, in all likelihood.'..."
What's just as exciting is that Kepler 78b shouldn't be there. Scientists have developed a model for how planetary systems develop that's been a good match with observations: until now. Applying that model to the Kepler 78 system puts Kepler 78b inside the star earlier in its existence.
That didn't happen, obviously, since the Kepler 78b is still there. As I've said before, it's nice when observations match theoretical predictions. When they don't, it's exciting: because we've got more to learn.
Typos?
I've learned to take numbers and other data from Space.com articles and other sources with a pound or two of salt. I enjoy their enthusiasm, but wish that someone would proof the things.In this case, Mr. Wall says that Kepler 78b is 400 light years from Earth. Other sources, including the Kepler Science Center and the MIT News Office say it's 700 light years out. On the other hand, the Harvard Gazette says 400 light years. Maybe Mr. Wall is a Harvard man.
Or maybe "400" is a typo.
The Kepler 78 planetary system can't be 400 and 700 light years away, so at least one of those numbers isn't right. My guess, since the folks with Kepler and MIT think it's 700, that the others intended to enter "700," and hit the "4" on their keypad by mistake. If their keyboards are like mine, the 4 and 7, 5 and 9, and some other pairs are easy to get mixed up.
Particularly when deadlines loom.
"What's Most Exciting"
(Cristina Sanchis Ojeda, via MIT News Office, used w/o permission.)
"Waking up to a new yearMy guess is that "what's most exciting" depends on which scientists you ask. This almost-Earth-size world is fascinating for quite a few reasons, including what's mentioned in this article.
MIT team discovers an exoplanet that orbits its star in 8.5 hours."
Jennifer Chu, MIT News Office (August 19, 2013)
"In the time it takes you to complete a single workday, or get a full night's sleep, a small fireball of a planet 700 light-years away has already completed an entire year.
"Researchers at MIT have discovered an Earth-sized exoplanet named Kepler 78b that whips around its host star in a mere 8.5 hours - one of the shortest orbital periods ever detected. The planet is extremely close to its star - its orbital radius is only about three times the radius of the star - and the scientists have estimated that its surface temperatures may be as high as 3,000 degrees Kelvin, or more than 5,000 degrees Fahrenheit. In such a scorching environment, the top layer of the planet is likely completely melted, creating a massive, roiling ocean of lava.
"What's most exciting to scientists is that they were able to detect light emitted by the planet - the first time that researchers have been able to do so for an exoplanet as small as Kepler 78b. This light, once analyzed with larger telescopes, may give scientists detailed information about the planet's surface composition and reflective properties.
"Kepler 78b is so close to its star that scientists hope to measure its gravitational influence on the star. Such information may be used to measure the planet's mass, which could make Kepler 78b the first Earth-sized planet outside our own solar system whose mass is known...."
"Kepler-78b, shown in image 1 in an artist's conception, is a mystery. Experts say it couldn't have formed so close to its star, nor could it have moved there. Image 2 compares Earth to the newly confirmed lava planet, while image 3 illustrates its tight orbit."
(Harvard Gazette)
(David A. Aguilar (CfA), via Harvard Gazette, used w/o permission.)
Image 1.
(David A. Aguilar (CfA), via Harvard Gazette, used w/o permission.)
Image 2.
(David A. Aguilar (CfA), via Harvard Gazette, used w/o permission.)
Image 3.
More:
- "Mystery world baffles astronomers"
"Kepler-78b is first known Earth-sized planet with an Earth-like density"
Harvard-Smithsonian Center for Astrophysics, Harvard Gazette (October 30, 2013) - "One year on Earth-sized exoplanet lasts 8.5 hours"
FoxNews.com (August 20, 2013) - "Transits and Occultations of an Earth-sized Planet in an 8.5 hr Orbit"
Roberto Sanchis-Ojeda, Saul Rappaport, Joshua N. Winn, Alan Levine, Michael C. Kotson, David W. Latham, and Lars A. Buchhave; The Astrophysical Journal Volume 774 Number 1 (August 16, 2013)
2. The Seven Worlds of KIC 11442793
"Seven-planet solar system found"At seven planets, KIC 11442793's planetary system sounds a lot like home: but on a smaller scale.
Paul Rincon and Melissa Hogenboom, BBC News (October 24, 2013)
"Astronomers may have identified one of the richest planetary systems yet.
"The discovery of a seventh planet around the dwarf star KIC 11442793 could be a record, according to two separate teams of researchers.
"The system bears some similarities to our own, but all seven planets orbit much closer to their host star, which lies some 2,500 light-years from Earth.
"The crowded solar system is described in two papers published on the pre-print server Arxiv.org...."
Depending on who's counting what, our star has eight, nine, or more planets: Mercury, Venus, Earth, Mars, Ceres, Jupiter, Saturn, Uranus, Neptune, Pluto, and maybe objects like Quaoar, Varuna, and Orcus. Ceres was called an asteroid in my youth, but it's big enough to qualify as a dwarf planet.
My guess is that we haven't:
- Discovered all of KIC 11442793's planets
- Settled on labels for
- 'Stuff orbiting other stuff'
- Stuff orbiting stars
- Ours
- Others
- Run out of things to learn
Humans, Complicated Cases, and Finding Planets
"One of the identifications was made by volunteers using the Planet Hunters website. The site was set up to allow volunteers to sift through the public data from Nasa's Kepler space telescope - which was launched to search for so-called exoplanets - worlds orbiting distant stars.I don't think that humans are better than computers, or that computers are better than humans, for solving problems. I do think that there's more to a human than the neural circuits in our heads, and that's another topic.
"Kepler uses the transit method to discover new planets, which entails looking for the dip in light as an alien world passes in front of its host star. But there is simply too much data for mission scientists to examine every light curve, so they developed computer programmes to search for the signature of a planetary transit....
"...'A seven-planet system is very complicated so you get a sense of why the automatic routine might have missed out - it gets confused by the presence of the other transits.
" 'Looking for these transits seems like a task that's perfectly designed for computers. But we keep finding, in these niche cases, in these odd cases, in these complicated cases that humans can beat the computers.'..."
We do seem to be really good at sorting out what makes sense from a welter of data. That knack uses our 'pattern recognition' circuits.
The best, clearest, shortest discussion of what humans and computers are good for that I've seen yet:
"Computers are designed to arrive at correct conclusions, based on huge amounts of data: all of which is precisely accurate.I'd tell you who wrote that: but I'm human, and forgot where I saw it.
"Human brains are designed to arrive at correct conclusions, based on very little data: most of which is wrong."
Somewhat-related posts:
- "Fusion Power, Terraforming, and Old Dutch Windmills"
(October 11, 2013)
Particularly - "Three Es: Exoplanets, Exobiology, and Evolution"
(October 4, 2013)
Particularly - "Life in the Universe: Learning Where to Look"
(September 20, 2013)
Particularly - "Gods, Demons, and Used Spaceship Dealers"
Drifting at the Edge of Time and Space (February 13, 2010) - "Earth May Not Be a 'Class M' Planet"
Apathetic Lemming of the North (December 5, 2009)
Particularly
2 comments:
"Humans are designed to come to correct conclusions based on very little data, most of which is wrong."
--Dad
Brigid, :)
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