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Thrilling Discovery of Seven Earth-Sized Planets Orbiting Nearby Star (theguardian.com)
At a press conference on Wednesday, NASA scientists announced that they have spotted seven Earth-sized planets orbiting closely around a small, ultra-cool star. The star is 39 light years away. From a report on The Guardian: It is the first time that so many Earth-sized planets have been found in orbit around the same star, an unexpected haul that suggests the Milky Way may be teeming with worlds that, in size and firmness underfoot at least, resemble our own rocky home. The planets closely circle a dwarf star named Trappist-1, which at 39 light years away makes the system a prime candidate to search for signs of life. Only marginally larger than Jupiter, the star shines with a feeble light about 2,000 times fainter than our sun. "The star is so small and cold that the seven planets are temperate, which means that they could have some liquid water and maybe life, by extension, on the surface," said Michael Gillon, an astrophysicist at the University of Liege in Belgium. [...] While the planets have Earth-like dimensions, their sizes ranging from 25 percent smaller to 10 percent larger, they could not be more different in other features. Most striking is how compact the planet's orbits are. Mercury, the innermost planet in the solar system, is six times farther from the sun than the outermost seventh planet is from Trappist-1.
Well yes, much in the same way one infers the presence of a stream of electrons from an electrical charge or the Big Bang from the CMBR, relative proportions of hydrogen, helium and lithium in the Universe and the red-shift of distant galaxies. Even a particle accelerator like the LHC at CERN does not in fact directly image subatomic particles. For chrissakes, what you "see" isn't a raw image, but is heavily processed by your nervous system, beginning right at the retina itself, then by the optic nerve and then by visual centers in the brain. In other words, what you "see" isn't actually the photons that the physical structures of the eye captures.
Lots of science is inference, seeing as many phenomenon cannot be directly observed. If you're saying inference is somehow questionable, then you're basically calling all form of observation questionable.
The world's burning. Moped Jesus spotted on I50. Details at 11.
Finding that many Earth-sized rocky bodies orbiting a star just 39 lightyears away, with the possibility that some of them may be able to have liquid water on their surface doesn't excite you? Did you have your sense of wonder and curiosity surgically removed?
The world's burning. Moped Jesus spotted on I50. Details at 11.
This is a red M class Dwarf star. The lack of radiation is the more immediate concern rather the excess of it. Red M class dwarf stars emit most of their radiation as infra-red, and barely emit any ultraviolet. If ultraviolet radiation is indeed a requirement for life, then this will be a problem. Total sterilization is unlikely, since the amount of energy hitting the planets will likely be similar to what the Earth is already getting.
Also, wrt tidal locking, the main concern would be that one side of the surface will be boiling while the other side will be freezing (one side gets all the sun, the other side gets none), which IS a concern wrt. life. Earthquakes are not a direct effect of tidal lock. That would be geological activity.
Of course, all of this is conjecture. We need to study these kinds of planets a bit more to know for sure. Hence, their importance.
Mars first. No need to run before you can crawl.
Though so far our record is to crawl to the moon, feel proud, then crawl back down our hole and declare the rest of the universe isn't that good anyway.
The blast of sterilizing radiation at that distance, combined with being tidally locked and probably wracked with catastrophic earthquakes at that distance would make life on these planets an unlikely impossibility.
The sun is a red dwarf and is 0.05% as bright as our sun. It has 8% of the mass of our sun and is 10% of the radius of our sun. It is much smaller, lighter and cooler. Not very much larger than Jupiter. The planets are likely to be tidally locked. Jupiter's Galilean moons are tidally locked to Jupiter, but they are not blasted by radiation. The study showed gravitational synchronization in their orbits, so that could cause earthquakes.
If the star were our sun the planets would be blasted wastelands tidally locked to their sun. I think the exciting point is that this system is 'only' 40 light years away, so we should be able to study it over the next few decades and learn much more. The planets are transiting their sun, as seen from earth, so we should be able to detect gas within their atmospheres through spectroscopy. Over the next few decades advanced space telescopes should help us gain a great deal of information on this system.
Could there be life> maybe. There is a whole lot to learn and a great many engineering challenges to solve to let us learn. For me that is more exciting than maybe a small chance of life.