Two temperate Earth-mass planets orbiting the nearby star GJ1002
arxiv.org
arxiv.org
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.
"The closeness of the host star to the Sun makes [it possible] for their atmosphere to be studied via high-contrast high-resolution spectroscopy."
Hopefully they can follow-up soon with those measurements. That could bring clarify to your fundamental questions.
[1]: https://en.wikipedia.org/wiki/Hydrothermal_vent_microbial_co...
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.
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
Ocean to the north and desert to the south and only a thin strip in between where to live and wage war in.
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.
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.
Edit: I found this paper about weather on tidally locked planets https://www.pnas.org/doi/10.1073/pnas.1315215111
But without a magnetic field, the only hydrogen is what is locked up in ice or other solids.
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?
1.4 solar masses and yet much dimmer than the Sun
This is not even physically possible unless the star is a post-main sequence white dwarf.
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.
Realistically if we wanted to look for life on a foreign object, we would probably start with the candidates in the solar system.
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
The warp factor table at [1] makes absolutely no sense.
Enterprise (the show) warp 4.6: 90 light years in 4 days.
Voyager warp 4.7: 10 light years in 3 weeks.
Enterprise (the show) warp 5: 50 light years in 3 months.
> 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?
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.
> 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.
Also known as the scenarium trace mineral commonly found in space.
hard a pass from me if the internet reception is not good
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.
For perspective, Voyager 1 has been hurtling through space since 1977 and has travelled a measly .002324439 lightyears.
The Universe is mind bogglingly big.
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.
But beyond that I know nothing
There's a wikipedia page for the concept at
This video on gravitational lensing blew my mind https://youtu.be/NQFqDKRAROI
What do you think the odds are of if it being done IRL?
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.
Lorentz factor γ = 1 / sqrt(1 - (v/c)²) = 1/sqrt(1 - 0.9²) = 2.29
(1-(1/1048800)²) c = 0.9999999999990908 c
For comparison, the protons at CERN only hit 0.999999991 c (https://public-archive.web.cern.ch/en/LHC/Facts-en.html) and the electrons at SLAC only hit 0.99999999995 c (https://www.slac.stanford.edu/pubs/slacpubs/5500/slac-pub-56...).
About 500 AU but it’s a design decision.
https://nssdc.gsfc.nasa.gov/planetary/titan/huygens_titan_06...
The lake is not liquid water, rather liquid hydrocarbons! That image was captured from the Huygens lander, you can see more images here:
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.”
Is this correct?
But no, it's not strictly correct. The paper gives the masses as 1.08±0.13Me (minimum mass 0.95Me) and 1.36±0.17Me (minimum mass 1.19Me.)
If those planets have little axial tilt and little variety in distance to their star, there should be little variety in climate on them.
[1] https://en.wikipedia.org/wiki/Axial_tilt#Extrasolar_planets