Scientists following up on Kepler observations learned that a bit over half of the objects tentatively identified as giant planets are brown dwarfs or stars.We've also learned that Saturn's moon Enceladus has a vast ocean under its icy surface: with all the ingredients needed for life.
- Kepler Data Analyzed: False Positives and Big Planets
- Enceladus Interplanetary Geyser Park and the Search for Extraterrestrial Life
Thinking and Humility
If you've read my 'science' posts before, you know why I think Earth isn't flat; the universe is billions, not thousands, of years old; poetry isn't science; and thinking is not a sin.Basically, it's because I think God created and creates this universe: and isn't a liar. Nothing we learn about this universe can interfere with faith because both come from God. (Genesis 1:1-31; John 14:6; Catechism of the Catholic Church, 159, 279, 301)
Science and technology, studying the universe and applying that knowledge, is part of being human. We're supposed to use the brains God gave us. (Catechism, 1730, 1831, 2292-2295, 2493)
There's being humble, too. Humility, in the Catholic sense, is not cherishing delusions of inadequacy. That's being crazy, and an almost-entirely different topic.
Humility is recognizing that God's God and I'm not.
"HUMILITY: The virtue by which a Christian acknowledges that God is the author of all good. Humility avoids inordinate ambition or pride, and provides the foundation for turning to God in prayer (2559). Voluntary humility can be described as 'poverty of spirit' (2546)."Accepting reality seems prudent. Insisting that God must conform to what we thought was true a few centuries or millennia back: not so much. (March 29, 2015; August 10, 2014)
(Catechism, Glossary, H)
Neighbors
I am quite certain that life exists elsewhere in this universe: or not. Right now, we don't know.Finding any sort of life, like the alien equivalent of bacteria, would be a huge discovery: but the 'jackpot' would be finding neighbors.
If we meet them during the next few centuries, I think the odds are that they'll be finding us. Either way, I'm pretty sure that reactions would be mixed. (August 2, 2015)
I like Brother Guy Consolmagno's opinion about extraterrestrial life. (July 31, 2015)
"...Frankly, if you think about it, any creatures on other planets, subject to the same laws of chemistry and physics as us, made of the same kinds of atoms, with an awareness and a will recognizably like ours would be at the very least our cousins in the cosmos. They would be so similar to us in all the essentials that I don't think you'd even have the right to call them aliens."The idea that we have a kind of solidarity with the universe isn't new. Daniel 2:79-81, St. Francis of Assisi's Laudes Creaturarum/Canticle of the Creatures/Canticle of the Sun before, and all that. (June 28, 2015; June 15, 2014)
("Brother Astronomer;" Chapter Three, Would You Baptize an Extraterrestrial? — Brother Guy Consolmagno (2000))
As for whether or not there's life on other worlds: like I've said before, that's God's decision. Not mine. (August 2, 2015)
1. Kepler Data Analyzed: False Positives and Big Planets
(From ESO/M. Kornmesser/Nick Risinger (skysurvey.org), via Space.com, used w/o permission.)
("Artist's illustration showing the giant, Jupiter-like exoplanet 51 Pegasi b, which in 1995 became the first alien world to be found around a sunlike star."
(Space.com))
"Half of Kepler's Giant Exoplanet Candidates Are False Positives: Study"The giant planet candidates Santerne's team were checking out were something at least as massive as Jupiter. They used the radial velocity method to analyze SOPHIE data — in other words, they looked hard at wobbling stars from July 2010 through July 2015.
Mike Wall, Space.com (December 11, 2015)
"More than half of the giant alien planet candidates detected by NASA's prolific Kepler space telescope are false positives, a new study suggests.
"A team of astronomers followed up on 129 huge potential exoplanets spotted by Kepler using a ground-based telescope and found that 52 percent of the objects are actually stars, while another 2 percent are strange 'failed stars' known as brown dwarfs.
" 'It was thought that the reliability of the Kepler exoplanets detection was very good — between 10 and 20 percent of them were not planets,' study lead author Alexandre Santerne, of the University of Porto in Portugal, said in a statement...."
The stars they found are eclipsing binaries, pairs of stars orbiting each other in a plane that's really close to us, so that each star crosses in front of its partner from our viewpoint.Brown dwarfs are more massive than the largest gas giant planet, but lighter than a star. They're not massive enough to support hydrogen-1 fusion, the thermonuclear 'fire' that heats main sequence stars.
Scientists still haven't decided where the line between gas giant planet and brown dwarf is. That's hardly surprising, since we didn't know they might exist until the 1960s, and weren't sure they really did until 1995.
Luhman16 A and B, about 6.5 light-years away, are the closest known brown dwarfs, and that's yet another topic.
Acronyms and Exoplanets
SOPHIE stands for Spectrographe pour l'Observation des Phénomènes des Intérieurs stellaires et des Exoplanètes.In English that'd be Observation of the Phenomena of Stellar Interiors and Exoplanets, or OPSIE — which sounds odd, somehow, and that's yet again another topic. Topics.
The SOPHIE échelle spectrograph is a high-resolution echelle spectrograph at the Haute-Provence Observatory in south-eastern France. Echelle spectrograph??
An echelle spectrograph uses an echelle grating, a special sort of diffraction grating with slits spaced at intervals equal to the wavelength of light being studied. It's like a prism, only different.
Anyway, analysis of the SOPHIE data showed how fast the stars were wobbling; Kepler's data showed the orbiting objects' diameters; so when they were done, Santerne's team knew how wide and how massive the star's orbital companions were. Some were too massive to be planets.
However, that left some 46% of the possible gas giant planets that apparently are planets. That's still a lot of big planets.
"...Kepler has been an incredibly successful planet hunter. To date, the observatory has discovered 1,030 bona fide alien worlds (more than half of all the confirmed exoplanets ever found), as well as another 3,660 "candidates" that await vetting by further observation or analysis...."The last I checked The Extrasolar Planet Catalog, which was December 16, 2015, scientists have confirmed more than two thousand planets orbiting other stars. That's 2,030 planets in 1,288 planetary systems: 501 in multiple planet systems.1
(Mike Wall, Space.com)
2. Enceladus Interplanetary Geyser Park and the Search for Extraterrestrial Life
(From Richard Bizley/SPL, via BBC News, used w/o permission.)
("The Enceladus Interplanetary Geyser Park: Might we go there someday?"
(BBC News))
"Enceladus: Does this moon hold a second genesis of life?"My high school science textbooks outlined what's required for life: water, rock or soil, and sunlight. Plants use water, rocks, soil, and sunlight; get eaten by animals or recycled by fungi and microbes; all of which eventually become part of the soil that plants use.
Jonathan Amos, BBC News (December 11, 2015)
"The mighty Cassini probe has made many great discoveries at Saturn, but none top its extraordinary revelations at Enceladus.
"What the plutonium-powered satellite has seen at this 500km-wide, ice-crusted moon is simply astounding.
"Cassini has pictured huge jets of water vapour and other materials spewing from cracks at its south pole.
"It's quite a spectacle, and it's unique in the Solar System, according to Carolyn Porco, who runs the camera system on the big spacecraft.
" 'It became a joke on our team that we had found the Enceladus Interplanetary Geyser Park, and that future generations may go there just for vacation,' she tells me in a Discovery programme all about Enceladus which goes out on the BBC World Service on Monday.
"But researchers are not laughing when they say this little world is among the best places to search for life beyond Earth.
"The plumbing for the jets leads to a vast body of water that may be 30-40km deep in places. And Cassini's instruments have been able to show, by flying through and sampling the emissions, that the conditions and - importantly - the chemistry in this subterranean ocean could support microbial life...."
Scientists knew that some critters live at the bottom of Earth's ocean, far from any sunlight: but the ones they'd found fed directly or indirectly on organic stuff drifting down from the sunlit regions.
Then they found critters thriving around hydrothermal vents on the ocean floor. I've talked about extremophiles and looking for life in the universe before. (December 5, 2014; April 18, 2014)
If critters live in the Enceladean ocean, they may cluster around thermal vents: like deep-sea life here on Earth, where bacteria 'eat' sulfur compounds like hydrogen sulfide, producing organic stuff that's consumed by other critters.2
That's a big "if." All we have now is strong evidence that life could exist there. We'll know a bit more after Cassini's last flyby of Enceladus tomorrow, but the probe's instruments weren't designed to look for life.3
Next Enceladus Mission: ELF?
(From NASA/JPL-Caltech/SSI, via BBC News, used w/o permission.)
"...Jonathan Lunine is an interdisciplinary scientist on the Cassini mission at Cornell University in Ithaca, New York. He has a concept for a future spacecraft he calls the Enceladus Life Finder (ELF).Lunine's ELF would carry mass spectrometers, instruments that shoot electrons at a sample, measuring the atomic and molecular debris knocked loose.
"This would be a smaller probe than the goliath currently orbiting Saturn, but what it would give up in size (and cost) it would more than compensate for with sophistication.
"Its instruments would be dedicated to the very specific job of analysing the contents of the jets for any chemistry associated with biology...."
(Jonathan Amos, BBC News)
ELF could sample spray from Enceladean geysers, detecting fatty acids, isoprenoids, and carbon isotopes used by life on Earth.
NASA turned down ELF when looking for new missions. One of the issues, apparently, was finding a power source for a Saturn-system probe. That far from the sun, solar panels would have to be huge; and plutonium batteries like the one in Cassini are rare items these days. Also expensive.
Even if ELF never gets off the ground, I'm pretty sure that someone will send a probe with similar instruments to Enceladus. Quite a few folks want to know if there's life elsewhere in the universe, and at the moment Enceladus is the most promising spot that our robot spacecraft can reach.
The south polar geysers may not be there by the time ELF or another probe arrives, though. It looks like they may have been fading since 2005. And that's still another topic. (Space.com (December 16, 2015))
More of how I see life, the universe, and all that:
- "Faith, Fear, and Flying Saucers"
(August 2, 2015)
Particularly - "Pluto, Earth 2.0, and Life in the Universe"
(July 31, 2015)
Particularly - "Alien Worlds, Martian Methane, Looking for Life"
(January 2, 2015)
Particularly - "DNA Test Hype; and Studying Life's Origins"
(December 5, 2014)
Particularly - "Harpooning the 'Rubber Duck' Comet; Public Safety — and Space Aliens"
(November 7, 2014)
Particularly
1 Finding new worlds:
- The Extrasolar Planet Catalog
The Extrasolar Planets Encyclopaedia; Exoplanet Team - Wikipedia
- List of exoplanets
- List of exoplanets
(Outdated: last updated September 28, 2015)
- List of exoplanets
- NASA
- Life on the Edge FAQ
Dr. David Noever - "Identification and Characterization of Extremophile Microorganisms with Significance to Astrobiology"
Asim K. Bej, Ph.D. (2002)
- Life on the Edge FAQ
- Wikipedia
- NASA/JPL
- Wikipedia
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