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JWST's first spectrum of a TRAPPIST-1 planet
- tempodox 3y agoI was hoping they would actually show that spectrum, but no dice.
- echelon 3y ago> cloud-free, hydrogen-rich atmospheres were ruled out with high confidence. This means that there appears to be no clear, extended atmosphere around TRAPPIST-1 b I will never not be amazed that we can read the atmospheric spectra of exoplanets.
- somenameforme 3y agoSpectroscopy. [1] The most amazing thing about it is how simple it really is. Each element has a unique absorption/emission scheme for 'light' / electromagnetic radiation. So light radiated from a body will have tell tale missing segments when broken down into its spectrum, absorbed by the atmosphere it passed through. Think about how light passed through a prism splits from white light into its rainbow colored components. It's the exact same thing. All you need to do is see what's missing, and you can discern the elemental composition of the atmosphere[s] that said light passed through. And it all started with Newton playing with a prism, and thinking beyond 'my, what pretty colors.' The really cool thing about this is that it also can tell you some things that defy 'common knowledge.' For instance the Moon actually has a persistent atmosphere, and it's made out of sodium! It's exceptionally thin, but it's there - and can be picked up by spectroscopy. [1] - https://en.wikipedia.org/wiki/Astronomical_spectroscopy https://en.wikipedia.org/wiki/Astronomical_spectroscopy
- dylan604 3y ago>The most amazing thing about it is how simple it really is what gets me isn't the lack of complexity, but the lack of light. holding a prism to capture the sun's light or a flash light or whatever is simple since there's so much of it. even in telescopes, stars are mere pixels.
- rburkej 3y agoNGL, my first thought was a planet full of beer and cheese.
- mrec 3y agoAnd nobody talking. Heaven.
- stronglikedan 3y agoThe combination of beer and nobody talking doesn't exist.
- marmakoide 3y agoNaturally occurring lakes of algae tasting like wheat and similar sugar content, and metabolized by fermentation from micro organism.
- baud147258 3y agoDrinking alone? As long as you don't start talking to yourself and/or to your imaginary friends
- MichaelMoser123 3y ago... imagine all that beer at the pub, and no one is joining in...
- wlesieutre 3y agoIf anyone's curious, the name comes from planets around the star having been discovered using the TRAnsiting Planets and PlanetesImals Small Telescope https://en.wikipedia.org/wiki/TRAPPIST https://en.wikipedia.org/wiki/TRAPPIST
- none_to_remain 3y agoThe name comes from Trappist beer. Belgian university
- deleted 3y ago[deleted]
- jug 3y agoToo bad the star is going to make observations within the habitable zone hard! This problem also sounds like one that can be extrapolated into more systems as those planets are going to be close to the star by necessity…? Frustrating that the resolving power of JWST is there even for those, but the star completely dominates the observations. I wonder if they could perform analysis over time and apply statistical models to subtract solar output from the data, knowing the orbital periods etc. But that’s just me being a layman here.
- perihelions 3y ago- "I wonder if they could perform analysis over time and apply statistical models to subtract solar output from the data, knowing the orbital periods etc. But that’s just me being a layman here." They do that in the paper. That's the "secondary eclipse", where the planet goes behind the star and they subtract the difference. https://iopscience.iop.org/article/10.3847/2041-8213/acf7c4 https://iopscience.iop.org/article/10.3847/2041-8213/acf7c4 [open access]
- ramraj07 3y agoGiven how much we know now about how inhospitable red dwarf star systems are, why are we continuing to focus on planets in such systems instead of planets in sun like stars?
- blincoln 3y agoAs the article mentions, this system is unusual, in that it has three Earth-sized planets in its habitable zone.
- TheBlight 3y agoI don't get the impression there's currently a bandwidth problem here that needs optimizing. It's also not completely clear how inhospitable to life they truly are. Being the most abundant type of star in the galaxy by far, it makes sense to study them very closely to at least rule out the potential for life.
- jl6 3y agoRegular solar flares could be bad for any lifeforms trying to get a stable civilization together, but on the other hand, all that energy arriving in the atmosphere could trigger some very life-conducive chemistry, similar to how we theorize that lightning was involved in our own primordial soup.
- radicalbyte 3y agoThe habitable zone is very close to the star; this results in a high probability of the planet being tidally locked and a high probability of being affected by solar flares.
- standardly 3y agoA tidally locked planet would be neat if civilization could exist there. One side would be constantly hot, and the other would be frozen, but there would exist a temperate climate zone in a longitudinal ring connecting the poles. Almost like a ring planet from Halo. I remember an interesting astrobotany paper hypothesizing that if plants were to evolve on a red dwarf planet, there would be selective pressure for them to be black rather than green (for maximum light absorption, as most light would be infrared).
- amriksohata 3y agoDoes this change theories around how gaseous clouds eventually formed stars and solar systems?
- malfist 3y agoNo, not at this time (and not expected to).
- ck2 3y agoNow I can't wait for European Extremely Large Telescope with several times the resolution (also the space Wide-Field Infrared Survey Telescope) btw PBS Nova has an awesome episode on JWST, how hard it was to get built and how it almost didn't get built because massively over budget ($10 Billion!) https://www.pbs.org/video/ultimate-space-telescope-gunryt/ https://www.pbs.org/video/ultimate-space-telescope-gunryt/ This is kind of a "part 2" follow-up after it was launched and "first light" https://www.pbs.org/video/new-eye-on-the-universe-zvzqn1/ https://www.pbs.org/video/new-eye-on-the-universe-zvzqn1/
- jamiek88 3y agoOoooh thanks for this! I always forget about Nova then like almost all of their programs, think I should watch more then promptly forget!
- dylan604 3y agoI started watching the Nova episode. I didn't realize the timing of the testing done in Houston during hurricane Harvey. As if the stress on getting JWST built wasn't enough, but now it's in the path of a massive hurricane that parked itself over the area dropping 40"+ of rain. Edit: just to add that I found the segment on the alignment process of the 18 mirrors an interesting puzzle. Once you've found all of the pieces, you still have to decide what mirror each part of image represents. I've aligned my telescope mirror's primary/secondary mirrors on terra firma, but you at least have a bit of a feel for how much you're adjusting. Doing that remotely from 1M miles away, just makes it that much cooler
- 1970-01-01 3y agoSo they are confident it is just a dumb rock, and it's time to move onto another planet. Good but very boring news.
- deleted 3y ago[deleted]
- malfist 3y agoA planet is hardly "just a dumb rock"
- explaininjs 3y agoDon’t bother. This guy doesn’t respond to anything that contradicts him. Would be cool to have a dashboard of some sort that provided “probability this HN user will respond when called out for speaking from their behind”.
- 1970-01-01 3y agoHow so?
- seventytwo 3y agoDoes this technique only work with systems that are edge-on so that the star light passes through the exoplanet atmosphere? Or can this work with reflected star light for systems that have orbits that face us?
- sbierwagen 3y agoEdge only. Fortunately, most of the exoplanets we know of were discovered by that exact method (by space telescopes that stared at a patch of stars for months at a time https://en.wikipedia.org/wiki/Kepler_space_telescope https://en.wikipedia.org/wiki/Kepler_space_telescope ) so it's just a matter of working down that list.
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- jbird11 3y agoI've always wondered, what determines which planet or solar system to observe? I guess I'd like to think we have a list of solar systems that are most likely to hold life and simply go down it from most likely to least likely but it surely can't be that reductive.
- sharlos201068 3y agoMy understanding is that most Earth-sized exoplanets these days are detected using telescopes performing a wide survey of entire sections of the sky, tracking periodic changes in the star's brightness or position (if the planet makes the star wobble). So they aren't really picking out specific stars intially. Once they've identified a candidate exoplanet, then they'll often try to confirm it using more direct/targetted observations.