Yes. To a fair approximation, the lifespan of a star on the Main Sequence is proportional to its mass to the power -2.5. Beyond the Main Sequence, there also should be no black dwarfs as no white dwarf will have had time to cool sufficiently.
Poll Where are all the aliens? Are they hiding?
- Thread starter valkyrie013
- Start date
Indeed. A black dwarf is a strictly theoretical object, one the universe won't see for many millions of years.
By some estimates, at least 10^15 years and perhaps never to reach as low as the CMBR effective temperature due to proton decay and interaction with WIMPs (if either exist). Some of the more massive white dwarfs (from 1.16 to 1.35 solar masses) might explode after some ridiculously long time like 10^1,100 years or even longer, due to pycnonuclear fusion to iron lowering the Chandrasekhar limit, but proton decay might prevent this (again, only if it exists).
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Not only radio - EM generally, neutrinos and other forms of radiation including gravitational waves - all limited to the speed of information c or less, of course. A Bracewell probe would try to open communication. A von Neumann (the correct spelling of his name) probe might seek to hide itself while harvesting matter and spawning copies for whatever purpose - benign, neutral or hostile. We'd only spot things like the Pioneer or Voyager probes if they were broadcasting. They're pretty small radar targets and would just seem like tiny extrasolar objects unless we got a close-up look. We didn't bother chasing after Oumuamua and it's quite odd.
Project Lyra might correct that.
https://en.m.wikipedia.org/wiki/Project_Lyra
My hope is that the very last SLS be INTERSTELLAR PROBE which would also double as Lyra. Block 2…NTR upper stage with NEP payload.
It would be a de facto interstellar mission without needing a true starship. Even if it is not a probe…we know it to be extrasolar material.
Wild nonsense…
https://www.coasttocoastam.com/article/richard-c-hoagland-links-images-121923/
As for Avi? Um…
https://www.space.com/alien-spherules-new-analysis-shows-likely-origin-is-earth
Now, there might be a chance for an extraterrestrial origin…just not what he was thinking:
https://en.m.wikipedia.org/wiki/Río_Cuarto_craters
The reason I bring that up is that years ago—before MYTHBUSTERS—Discovery Channel had a program called THREE MINUTES TO IMPACT that suggested that some asteroids may come in at very shallow angles.
If there is anything to this…maybe a seamount/guyot is actually a nickel/iron slug in disguise…with the usual encrustations atop them, and metals dissolved out of them:
https://www.nature.com/articles/s43017-020-0027-0#:~:text=Deep-ocean polymetallic nodules (also,,4,5,6.
So not only might we get an interstellar mission without going interstellar distances—perhaps we can get asteroid mining without any kind of spaceflight at all?
About…probes
https://www.mirror.co.uk/news/weird-news/aliens-seeking-probe-humans-earth-32120332
https://en.m.wikipedia.org/wiki/Project_Lyra
My hope is that the very last SLS be INTERSTELLAR PROBE which would also double as Lyra. Block 2…NTR upper stage with NEP payload.
It would be a de facto interstellar mission without needing a true starship. Even if it is not a probe…we know it to be extrasolar material.
Wild nonsense…
https://www.coasttocoastam.com/article/richard-c-hoagland-links-images-121923/
As for Avi? Um…
https://www.space.com/alien-spherules-new-analysis-shows-likely-origin-is-earth
Now, there might be a chance for an extraterrestrial origin…just not what he was thinking:
https://en.m.wikipedia.org/wiki/Río_Cuarto_craters
The reason I bring that up is that years ago—before MYTHBUSTERS—Discovery Channel had a program called THREE MINUTES TO IMPACT that suggested that some asteroids may come in at very shallow angles.
If there is anything to this…maybe a seamount/guyot is actually a nickel/iron slug in disguise…with the usual encrustations atop them, and metals dissolved out of them:
https://www.nature.com/articles/s43017-020-0027-0#:~:text=Deep-ocean polymetallic nodules (also,,4,5,6.
So not only might we get an interstellar mission without going interstellar distances—perhaps we can get asteroid mining without any kind of spaceflight at all?
About…probes
https://www.mirror.co.uk/news/weird-news/aliens-seeking-probe-humans-earth-32120332
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Avi Loeb does seem to suffer from confirmation bias, but that is true of all of us to a greater or lesser extent. Oumuamua does deserve a close inspection, but someone has to be willing to stump up the money to fund a suitable mission to chase it down. Even if that were possible, it would probably only be a rapid flyby. Taking over twenty years requires a lot of patience - it would represent a big chunk of most people's careers - possibly spent chasing what is just a big rock covered in tholins (red goo).
None of those are pressing concerns for the people in charge of the money. That's why we don't live in 2001/2010 world nor in For All Mankind world. The returns don't seem worth a big investment while terrestrial resources are cheaper and easier to exploit. Chasing after a weird rock is a hard sell.
Interstellar probe guys are really pushing for a flight…
https://interstellarprobe.jhuapl.edu/
And DARPA wants a NTR.
But most importantly there does seem to be Mars fatigue. So Lyra might have a lot of support coming from a lot of different fiefdoms if they play their cards right and link everything to Lyra to make a popular splash.
It beats JPL announcing they found water on Mars every six months hoping for a reaction.
That dog won’t hunt.
https://interstellarprobe.jhuapl.edu/
And DARPA wants a NTR.
But most importantly there does seem to be Mars fatigue. So Lyra might have a lot of support coming from a lot of different fiefdoms if they play their cards right and link everything to Lyra to make a popular splash.
It beats JPL announcing they found water on Mars every six months hoping for a reaction.
That dog won’t hunt.
Who wants to be stuck on Barsoom with Elon?
There is a lot more research on microgravity and living in it (and its not good) but virtually nothing about fractional G living, apart from a few hours from Apollo missions.Is it even possible for humans to live in Mars long term? Gravity seems a tad too low for that, and no I don't want to come anywhere near Musk..
Mars does not seem like the best place to find out. It's too far from Earth. We have a perfectly fine fractional gravity well 384000km away. Easier to get to than even trying to build a spinning station, at this point. It could turn out that for the most part, humans do fine in low-g, or maybe there are development issues that need correcting, or that children can't be properly conceived natrually (ectopic pregnancy) or develop in infancy properly.
BTW nice scooter in your profile pic. is that a Piaggio Liberty?
I think that space habitats are the way to go, yes, complicated, probably REALLY expensive but they'll provide 1g, an atmosphere like we have on Earth, you can throw a lot of them in the sun's orbit and you can move them if a gigantic rock is coming for them.. 
That scooter is a 50cc Kinroad Windbell 2, I have one of those, it's a Chinese copy of the Kymco Filly, mine is almost 19 years old and at the moment only a pile of parts and a bare frame, I'm going to restore it from the frame up again to learn about scooters and how they work, I have a 2021 Kymco Agility as well, I already did a full service on that one but I want to know all the ins and out of those.
It's kinda a miracle the old Kinroad even made it this far, it was neglected and almost scrapped by the previous owner, he tried to repair it because it had died on him and I bought this one and another non runner, A Xinling for 50 Euros, the Xinling is also a copy of the Kymco Filly, together with a friend I could make on working scooter out of the two, that was 5 years ago.
That scooter is a 50cc Kinroad Windbell 2, I have one of those, it's a Chinese copy of the Kymco Filly, mine is almost 19 years old and at the moment only a pile of parts and a bare frame, I'm going to restore it from the frame up again to learn about scooters and how they work, I have a 2021 Kymco Agility as well, I already did a full service on that one but I want to know all the ins and out of those.
It's kinda a miracle the old Kinroad even made it this far, it was neglected and almost scrapped by the previous owner, he tried to repair it because it had died on him and I bought this one and another non runner, A Xinling for 50 Euros, the Xinling is also a copy of the Kymco Filly, together with a friend I could make on working scooter out of the two, that was 5 years ago.
Do we know people cope well with the Coriolis effects of rotating habitats?
As a child of 12, I coped alright in a rotating-drum Round Up* fairground attraction - I didn't feel giddy or sick at all - but that was for only a short period. I enjoyed the experience immensely, so I went on it three times. Oddly, the difference in acceleration that I perceived between the top and bottom of the ride, when it was nearly vertical, was barely noticeable. I didn't feel dizzy stepping off the ride as presumably the fluid in my semi-circular canals had had chance to readjust as the drum decelerated. However, I don't believe there's any data on the physiological effects of living in a rotating constant-acceleration environment. Presumably, a large radius (r) of rotation would mitigate such effects. **
* Round Up (ride) - Wikipedia
** The inward centripetal force due to rotation is -mωx(rxω) = -mrω², where m is the mass of an object in the rotating frame of reference and ω is the angular velocity in radians per second. r and ω are the vectors corresponding to the scalars r and ω. ω is directed along the axis of rotation according to the right-hand rule. x is the symbol for the vector cross product. Centrifugal force is the outward reaction to the centripetal force, and so equals mrω². Coriolis force is -2m(vxω), where v is the velocity vector of an object with respect to the rotating frame of reference. For a given desired magnitude of centrifugal acceleration, ω varies as 1/√r, so Coriolis force varies as 1/√r. Double the radius of rotation and the Coriolis effect diminishes by about 29.3%. The effect is maximal for v and ω at π/2 radians (right angles) to each other and equal to zero for zero (or π) radians.
As a child of 12, I coped alright in a rotating-drum Round Up* fairground attraction - I didn't feel giddy or sick at all - but that was for only a short period. I enjoyed the experience immensely, so I went on it three times. Oddly, the difference in acceleration that I perceived between the top and bottom of the ride, when it was nearly vertical, was barely noticeable. I didn't feel dizzy stepping off the ride as presumably the fluid in my semi-circular canals had had chance to readjust as the drum decelerated. However, I don't believe there's any data on the physiological effects of living in a rotating constant-acceleration environment. Presumably, a large radius (r) of rotation would mitigate such effects. **
* Round Up (ride) - Wikipedia
** The inward centripetal force due to rotation is -mωx(rxω) = -mrω², where m is the mass of an object in the rotating frame of reference and ω is the angular velocity in radians per second. r and ω are the vectors corresponding to the scalars r and ω. ω is directed along the axis of rotation according to the right-hand rule. x is the symbol for the vector cross product. Centrifugal force is the outward reaction to the centripetal force, and so equals mrω². Coriolis force is -2m(vxω), where v is the velocity vector of an object with respect to the rotating frame of reference. For a given desired magnitude of centrifugal acceleration, ω varies as 1/√r, so Coriolis force varies as 1/√r. Double the radius of rotation and the Coriolis effect diminishes by about 29.3%. The effect is maximal for v and ω at π/2 radians (right angles) to each other and equal to zero for zero (or π) radians.
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^^ Seems that a space habitat of sufficient size won't have much of a issue with the coriolis effect, in short the bigger the better.
https://en.wikipedia.org/wiki/Space_habitat#Artificial_gravity
https://en.wikipedia.org/wiki/Space_habitat#Artificial_gravity
Kymco's vehicle naming department must be an interesting place to work. I still remember when they sold the "Bet And Win." I really like Kymco's. I have had a couple. We have an old Agility 125 that's become something of a hand-me down through the family. Currently one of my daughters owns it. It hasn't run in a few months so the carb is probably gummed up and the battery is dead. It would come back to life yet again, if needed. The last Kymco I had was the Like 150i. It was a practical little machine but I thought I needed something freeway capable and sold it. In the end I didn't and kind of regretted letting the thing go.That scooter is a 50cc Kinroad Windbell 2, I have one of those, it's a Chinese copy of the Kymco Filly, mine is almost 19 years old and at the moment only a pile of parts and a bare frame, I'm going to restore it from the frame up again to learn about scooters and how they work, I have a 2021 Kymco Agility as well, I already did a full service on that one but I want to know all the ins and out of those.
It's kinda a miracle the old Kinroad even made it this far, it was neglected and almost scrapped by the previous owner, he tried to repair it because it had died on him and I bought this one and another non runner, A Xinling for 50 Euros, the Xinling is also a copy of the Kymco Filly, together with a friend I could make on working scooter out of the two, that was 5 years ago.
The Agility I have is the 50cc version, it runs far better than the old Kinroad, road handling and brakes are very good on the machine, I just can't figure out the fuel system, it's Euro4 compliant and it has a carburator BUT also all the usual sensors, solenoids and computery tech thingies a fuel injection has, so kinda a fuel injection system that doesn't inject. 
The last few years Kymco has made a lot of nice scooters, their 300-400 and up class machines are really nice.
As for the topic, seems there's a lot of palaver going on with UFO's, aliens and what not so maybe they're not hiding at all..
The last few years Kymco has made a lot of nice scooters, their 300-400 and up class machines are really nice.
As for the topic, seems there's a lot of palaver going on with UFO's, aliens and what not so maybe they're not hiding at all..
Nah—I want to be his dealer.
I want rights to Titan’s vast seas of methane-
https://www.bbc.com/news/science-environment-25360516.amp
https://www.spaceflightinsider.com/...-very-different-potentially-habitable-worlds/
I want to say one word….plastics
If I were an investor, I'd want to see the costed business plan. It's a long way to Titan and back. Also, do we want more carbon dumping in our ecosphere? If you're using the methane off Earth, that's not a problem, I guess.
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