Red dwarf stars take up to 100 million years to settle down to the main sequence. Before that time, they are more luminous. During that period, these planets would not have been habitable and may have lost their water to space.
Red dwarfs also subject their planets in the putative habitable zone to much stronger stellar winds and flare radiation, which makes survival of their atmospheres problematic.
With our current methods we really only are able to detect rocky planets if they are close to a red dwarf and reasonably big.
It’s a bit like losing your key and looking below the street light because that’s the only place you can see - only that the street is littered with millions of potential keys anyway.
All these planets are necessarily tidally-locked to their star.
That represents an extremely poor environment to try to evolve life in. The only temperate place would be a ring at the terminator with the sun permanently just above the horizon.
With a very massive moon -- or a double planet, like Pluto/Charon, it might be possible to avoid tidal lock.
One of he planets receives 0.67, and the other, 0.257 of the Sun's light flux. The sun-facing surface, with the star directly above, may be the most habitable part, while the other side is likely colder than Antarctica.
With an ocean of liquid water evaporating on the sunlit side and condensing away from it, but flowing back through the ocean (and even rivers), the sunlit area may (theoretically) have relatively a temperate climate, as opposed to being a star-scorched dry desert.
This system is less than 5 parsecs / 16 LY from Sun, which likely makes it one of the systems more amenable to detailed research, as bigger telescopes become available.
More probably up to an equilibrium. Everything getting to the cold side will freeze and stay there but it must get there first.
My naive model: atmosphere on the warm side goes up, moves with hot humid air toward the cold side, goes down and back to the warm one with cold dry air.
Less naive model: we have three large convection cells here on Earth between the pole and the equator. Maybe they have several cells there too. That could slow down the transfer.
Furthermore dry is never 100% dry and when there is little water left the transfer will slow down. How much water will be left and for how long, I can't say. There could be the equilibrium I'm thinking about or not.
Other variables: volcanoes melt stuff locally, glaciers flow to lower ground, continents move.
The migration of water to the dark side changes the center of mass for the planet, right? Might that be enough, especially if there are any other bodies around to throw in some chaos, to pull the ice back into the warmer region?
Right, but not that's the same thing I'm wondering about. I'm wondering if the change in mass distribution due to ice migration might set things out of balance such that movement is possible. Further, that could still happen with effective tidal lock. Perhaps it's a "punctuated equilibrium" kind of thing where it's stable for a relatively long period until enough ice builds on the dark side that the planet "rolls" and stays in that position until enough ice melts and migrates again.
Life on such a world wouldn’t be so bad. It’s basically an inverted ring world. Belief systems would arise to discourage inhabitants from going too far off the ring, either into the burning desert eternally punished by the sun or the icy tundra shrouded in eternal darkness.
An advanced version of this civilization might think of the Earth as uninhabitable: how would you power anything without a builtin planet-scale, locally operable gradient?
At first armies can march in one direction of the ring or the other, with every natural defense point being sort of a Thermopilae situation
Then, technology progresses and certain machines may allow smaller groups to traverse outward for limited periods of time. Analogous to our submarines?
Would then flight make the world "flat" and globalized?
They can't lay cables across the scorching dor icy deserts, so worldwide comm must either follow the ring or be satellite-based
It's possible that such planets could have abiotic oxygen atmospheres, from water photolysed by intense UV radiation from the star. The hydrogen would escape to space. For that reason, even if oxygen (or ozone) is detected, it would not necessarily be a sign of life.
The presence of abiotic oxygen could help develop oxygen-breathing life, the same way as abiotic sulfur gives rise to teeming spots of life on the bottom of Earth oceans [1].
Any concrete numbers on that? I'd speculate there'd only be trace amounts: solar photochemistry is pretty slow, and rock weathering eats up any free molecular oxygen. Not sure of the relative rates.
The interesting fact is that we find this kind of planets in the very narrow settings we are able to look for them. That means they are probably everywhere.
Realistically if we wanted to look for life on a foreign object, we would probably start with the candidates in the solar system.
The planets are very close to their star, too: 0.046 and 0.074 au. The star is roughly 1.4 solar masses and yet much dimmer than the Sun. It is a very different solar system than ours.
Only 15.8 lightyears away. Unfortunately I can’t find an estimate for the age but it’s a main sequence red dwarf with under 0.35 solar masses which implies it can burn for much longer than our sun - on the order of trillions of years: https://en.m.wikipedia.org/wiki/Red_dwarf
> Star Trek: The Next Generation Technical Manual (p. 55) states the actual speed values of a warp factor are dependent upon interstellar conditions, for example gas density, electric and magnetic fields in different regions of the galaxy, and fluctuations of the subspace domain. Also quantum drag forces and motive power oscillation cause energy penalties to a ship using warp drive.
Depends on road conditions, very convenient for plot.
> Although formulas to calculate a relative speed from a warp factor have existed in the writer's guides, these were rarely used for reference in the episodes and films.
They just winged it with the technobabble. They retconned it by explaining that it’s a relativistic measurement which take into account gravity wells and ship size. I.e. even warp factor 10 (infinite speed in Voyager) might not be enough to escape a black hole if it gets too close.
Edit: the ENT/VOY comparison makes no sense even with the retcon IMO, how is warp 4.6 in a mid-22nd century ship an order of magnitude faster than warp 4.7 in a 24th century ship?
>Edit: the ENT/VOY comparison makes no sense even with the retcon IMO, how is warp 4.6 in a mid-22nd century ship an order of magnitude faster than warp 4.7 in a 24th century ship?
Emissions. ;)
I mean there was a TNG episode where they limited warp to factor 5 because of space emissions destroying the space environment or something like that.
Looks like they analyzed two datasets: one captured by a telescope in Chile, the other in Spain. We don’t hear about ground based telescopes in the news, I wish they were covered more often.
FWIW, four days ago there was https://news.ycombinator.com/item?id=33936559 , "Yale device delivers data from ‘Hell Planet,’ leads astronomers to its orbit", from a device "installed at the Lowell Observatory’s Lowell Discovery Telescope in Arizona".
Seven days ago was https://news.ycombinator.com/item?id=33866917 , "Bright flash is a black hole jet pointing at Earth, astronomers say", from observations at the Zwicky Transient Facility.
One big problem (besides getting out there - hehe) is that you are looking in one very particular direction and need to move big distances (at a distance of ~500 au from the sun) to look elsewhere. I guess you could wait until the planet you are aiming at does another orbit around its star and flies through your point of focus again.
PS Voyager launched in 1971 and is now at 158 au! These distances are truly vast. 1 light year is 63241 au.
This is the space project that most excites me and the one I most hope we solve in my lifetime. Much more interesting than Mars (not that you can't do both).
I don’t know anything specific about what the parent is proposing, but I imagine it is using the mass of the sun as a gravitational lens. Because of the solar radiation there isn’t really much sunlight (read:any) that is directly reflected to an observer peering on the edge of the sun.. light travels in straight lines.
Basically, the way scientists used a solar eclipse to confirm the theory of relativity and gravitational lensing of stars ‘behind’ the sun to in front of it. Or like the way certain objects were lensed in the massive JWST shot that came out a couple months ago.
Or are mindbogglingly slow.
If we can reach 90% of lightspeed we would have a good Lorentz number to travel the whole milkeyway in a few weeks. We would see a very different earth though when we come back.
To travel 87,400 light years at near light speed, in a subjective time of a month requires a dilation of 87400 years * 12 months / year = 1048800, with a speed of:
(1-(1/1048800)²) c = 0.9999999999990908 c
which is about 0.27 mm/s slower than the speed of light.
Maybe we’ll live long enough to see the completion of either solar gravitational lensing telescope or earth atmospheric lensing one. Either will (theoretically) let us imagine the surface features on extrasolar planets.
It’s not even a rounding error at the scale of our own galaxy (not joking: the measurement error for the size of the galaxy is something like +/-3kLY). May as well be next door. 15 LY is very close.
Nothing new, there are plenty of similar planets discovered around red dwarfs. Unfortunately, there are none found around the g-type stars and that's where the copy of earth ultimately should be possible.
using the following sentence, tell me how big are the planets comparing to earth: “We report the discovery[rest of the paper]..”
It gave me this: “ The two planets orbiting GJ~1002 have minimum masses of 1.08 and 1.36 Earth masses, respectively. This means they are roughly the same size as Earth.”
Orbital period in itself is just a number. Interesting variable is how does the climate on planet change during it. On Earth climate gets affected because of axial tilt of the planet, giving different hemisphere different amount of solar energy during a year (due to length of a day and Sun path on the sky).
If those planets have little axial tilt and little variety in distance to their star, there should be little variety in climate on them.
Since it is tidally locked around a low mass star, axial tilt should be near 0 and seasons should not exist [1]. Tidally locked also means much higher temperature than the estimated average (231K or -42C for the hotter one) on the sunny side and much lower ones on the dark side.
There are other ways for a planet to become tidally locked, for example Mercury is in a 3:2 resonance with the Sun. And if there is an atmosphere or a sufficiently deep ocean then even for a 1:1 tidally locked planet the temperature gradient from the light to dark side won't be too extreme.
Sure, there would just be no seasons. Everyday would just be roughly the same temperature as every other day. If the orbit is very eccentric, maybe 3-4 days would be like a brisk fall day, and 3-4 days would be like a hot summer day, and the rest would all hover around that average.
Red dwarfs also subject their planets in the putative habitable zone to much stronger stellar winds and flare radiation, which makes survival of their atmospheres problematic.