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. ... )
