Now 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!)
I 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
> 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.
Spectroscopy. [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.
>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.
Given 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?
I 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.
Regular 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.
The 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.
A 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).
You could also put solar up along the edge and even on the hot side and have tons of energy with no need for storage. It’d be like a poor man’s Dyson sphere.
Neat idea. Imagine getting solar/thermal energy from one half of the planet, and housing supercomputers and genetic databanks on the cold side, with population centers living in the temperate ring.
Or, the rich people could live in the temperate zone while the poor people choose between burning and freezing. Brb, writing a dystopian sci-fi.
"The discovery of the TRAPPIST-1 planets drew widespread attention in major world newspapers, social media, streaming television and websites.[302][303] As of 2017, the discovery of TRAPPIST-1 led to the largest single-day web traffic to the NASA website.[304] NASA started a public campaign on Twitter to find names for the planets, which drew responses of varying seriousness, although the names of the planets will be decided by the International Astronomical Union.[305]"
I think the public interest in it might be driving it? 40 light years is also kinda near to us, which might make it more interesting than Sun like systems if these are 100+ light years for example, if we were to want to do something about a possible detection.
Edit0: We don't know much of what conditions drive the genesis of life or where it might survive, so I'm not entirely sure that looking at red dwarves are a waste of time in a search for life.
They are also doing fundamental work in clearing up the influence of the star on their measurements!
Of the 131 stars and sub-stellar objects within 20 light years of the Earth, 101 are red or brown dwarfs. JWST/NIRISS has limited resolution, it's not going to be shooting spectra of exoplanet atmospheres of systems 50,000 light years away. They're just measuring every exoplanet system.
If you look up on a dark night, you can see 5 to 10 thousand stars. For every star you see there are 8 red dwarves. Not one of them is visible to the naked eye.
No red dwarf has died of old age yet. They live trillions of years and the universe isn't old enough.
Proxima Centauri might not be part of the centauri system. It's orbit is so long (80,000 years) that we can't tell if it is orbiting Alpha and Beta or just drifting by.
Since they are flare stars (suddenly increase 10 - 50 percent in brightness), there were a few minutes in 2015 where if you knew where to look you could see it.
The book (and netflix show) the three body problem is about aliens from the centauri star system.
w/apologies to JRR Tolkein, who said the correct word is dwarves.
* this is all from memory, might want to verify it.
It is funny to consider that most of the Milky Way is too dim to see. "Dark" matter. Of those 131 closest stars, only 22 are eye-visible. Only 6 are larger than Sol! WISE 0855−0714 is a mere 7.4 light years away and wasn't discovered until we started putting infrared telescopes in orbit.
Heck, TRAPPIST-1 itself isn't eye-visible. It's only slightly bigger than Jupiter! But these systems are hugely overrepresented in exoplanet surveys-- since we've only been hunting for exoplanets for a decade or so via the transit method, most of them have been found orbiting red dwarfs: the host star is so dim that transits take a big chunk out of their light curve, and the planets huddled up close to the star orbit so quickly that you can get the required three transits in a mere ten years of observation time.
It's a safe bet that there are gas giants like Neptune out there, but by the transit method it would take four centuries to find them! We invented the "hot Jupiter" category after Kepler launched, without nothing that we won't ever find "normal" gas giants without interstellar probes or space telescopes 10 km across.
because you need 3 transits for a positive detection of a exoplanet. And given that the habitable planet around a sun like star is anything from 250 - 700 days the observation time is too expensive so they focus on red dwarfs instead. I also find it pretty annoying as well, especially when science communicators try and extrapolate observations on red dwarfs on what is typical extrasolar system.
Baja has a great point, but I think another one beyond the transit time is relative size.
Unless there's a jovian planet with life out there your best bet at measuring a regular sized planet is around a small stars. Dwarfs.
When we had our massive planet surveys measuring transits we found a shit ton of jovian's around stars and some earth sized planets around smaller stars.
Time to measure transit and relative size are king.
> The magnetic fields' arrangement and intensity are responsible for areas of intense activity on the solar surface. For our Sun, these areas appear darker and are called sunspots, which have been found to occur in areas where solar flares are released.
> Solar flares from red dwarfs previously measured can be 100-1,000 times more potent than those released by our Sun. In 2019, Proxima Centauri, a red dwarf, let out a flare 14,000 times brighter than its pre-flare brightness.
> Solar flares are sometimes followed by hot plasma sent out from the star called coronal mass ejections (CMEs). Its scorching temperatures can blow strip away the atmospheres of planets and even boil away liquid water from the planet's surface, reducing the likelihood of it hosting life.
(Tangent to the tangent - https://youtu.be/FF_e5eYgJ3Y is a neat video - Close Encounter with a CME (Coronal Mass Ejection) :: On Sept. 5, 2022, NASA's Parker Solar Probe was about to make its 13th close approach to the Sun when a coronal mass ejection (CME) -- a powerful explosion of magnetic fields and plasma -- erupted right in front of it. ... )
Too 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.
- "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.
I'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.
My 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.
Does 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?
Edge 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 ) so it's just a matter of working down that list.
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/
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/