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https://www.nasa.gov/general/direct-multipixel-imaging-and-s...
Of course, getting the telescope into place, steering it, etc. - that's the hard part.
Surely it has happened. They must have all spotted our planet millions of years ago and must be watching us with a continuous high-resolution feed. They've seen our dinosaurs. Their interest will really be piqued when they finally see us invent electricity, though that might be some time in the future for them.
Perhaps even gravitational lensing is primitive to them. Perhaps they're able to break and manipulate physics and peer directly into our light cone, breaking the speed of light. Perhaps through direct wormholes they're already here - computronium in the very oxygen atoms that surround us. In rock silicates, in the air you breathe, in your hemes, in your brain. Calculating.
But perhaps we're the only intelligent species in the entire universe. That is also a possibility. Some big names in astrophysics, such as David Kipping, suggest strongly that we should not rule out that hypothesis. I find his suggestions haunting and beautiful at the same time. You need to watch his videos, and this is a good start: https://www.youtube.com/watch?v=PqEmYU8Y_rI
And finally, it may be that we're all just a historical simulation. Or maybe that's ascribing too much importance to ourselves. Maybe we're just a slop simulation on some AI's plaything, existing for no reason at all. Background NPCs with self-importance, ephemeral existences. But procedural generation at scale isn't really all too different from the laws of the physical universe itself.
The scale of the universe fills me with awe. Every time I think about it, my worries about random algo-rage and clickbait fades away to nothing. It deeply contextualizes our short time here.
They may be planted by alien AI to lull us into false sense of security.
Edit: My point is that you can't "build" such a thing and later point it somewhere-- you have to fly the camera part of the "telescope" about 3 times as far as voyager 1 went, exactly opposite of your observation target, and it is not gonna stay there for too long either.
As long as we improve rapidly at both drone-building and exoplanet target selection, it is not really gonna be worthwhile because both the drone hardware and the target will be hopelessly obsolete before we even get halfway to the observation point.
And if you circularize (which is expensive to do in delta-v), you minimize the time window you have for observation (because you're basically pointing your speed vector straight to outside of your observation cone).
Turning off the labels, aliens would probably assume that the world is naturally full of green stuff that is dealing with some strange grey infestation.
…would you? The lensing would occur right at the apparent surface of the sun.
Close enough that we could probably develop a probe to get there in the next few centuries and check it out. What are the current popular candidates for propulsion systems capable of accelerating to near the speed of light?
750 years is hard for me to get excited about even as a vampire.
And probing the universe outside the Milky Way? Forget about it.
But even at 0.12c, we are looking at 400 years to get there. And we'd be zooming by at 12% the speed of light. If we want to slow down a bit that'd add hundreds of billions to the cost.
It might be worth waiting another century to see if we can come up with a faster design in that time. Not like closer targets like Alpha Centauri, where the thing stopping us is mostly just the absurd cost
That’s the really hard part. If it’s almost science fiction to accelerate to 0.12c, it’s certainly much more difficult to slow down. At that speed we’d travel and pass this small system in mere minutes.
Those 190km/s of the Parker solar probe were, crucially, periapsis speed.
This is a bit like bouncing a rubber ball from a building, measuring its speed at ground level and then going: "Given our fastest achieved speed, we expect to hit the cloud level in <10s".
~200km/s sustained speed is already insanely optimistic for anything we could realistically build in the next half century, so your position is even more ironclad than it looks at first glance.
I still hold on to the idea that very long term we might make strides in our own solar system, but it is a depressingly-longer timescale than I always used to believe.
Unless we have some magic-level shift in our understanding of physics, we're never getting anything beyond Von Neumann probes to other stars, and even then we're talking thousands of years.
Clearly, right now we cannot. This is one of the worst obstacles to progress in these areas that I see, and I don't see any obvious way to fix it.
The situation we're currently in would've been utterly unfathomable to me 30 years ago. I have lost a great deal of the hope and optimism I held in the past. Interstellar exploration is but one of many fields where we are suffering due to short term thinking.
If you think of one, bring it up.
assuming we can make it another few centuries, which seems increasingly unlikely.
other ideas: 1. be way more patient 2. anti matter based propulsion (more out there than solar sails) 3. nuclear bomb based propulsion
One issue is as you get to these speed little bits of dust will anhillate the probe, so you need some kind of shielding, raising the mass budget, making it all the harder. A solar sail has to be able to survive holes getting poked it in it and still working, etc.
This also goes for aliens visiting Earth. Interstellar travel is just so impractical that I don’t think anyone has come on safari to Earth.
(No punchline; I just think that's cool. I understand that the real problem is the rare dust grain, not the ubiquitous gas.)
What's exciting to me is that the existence of such a planet provides fuel for more research into the field.
And work out safe systems for hibernation, maybe rotate the crew in shifts
Oh yeah this is the stuff of science fiction coming to life
Actually, it's a great question. Even if we have single photon sensitivity detectors, just what kind of power would a laser need? Or would it be some other area of the emf spectrum? Or some other kind of communication? Sci fi ventures into gravitational waves sometimes
Well, if they observed not only a planet orbiting the star but also the planet's atmosphere, it must not be a very "distant" star.
Yeah, but not that much.
Due to the density of the planet they believe it could be a water world, or a mostly-icy world due to the lack of hydrogen found, and the lower atmosphere could consist of nitrogen, water vapor, and carbon dioxide. Since the host star is very inactive, there's little atmospheric erosion that would strip away a heavier atmosphere.
* https://news.ycombinator.com/item?id=48939742
NASA has a neat exoplanet catalog where you can also switch to its solar system view
* https://science.nasa.gov/exoplanet-catalog/lhs-1140-b/
Super-Earths are interesting but not technically habitable, at least not by humanoids, the gravity would be insane
There are new telescopes and techniques coming online really soon that can potentially find closer to Earth-sized planets but they probably won't be within 50 light years
adding: hmm maybe gravity not too horrible on 1140b but still INTENSE
(assuming Google's "AI" is correct)
> Gravity Formula: \frac{Mass}{Radius^2}\)Calculation: \(5.6 \div (1.73)^2 = 5.6 \div 2.9929 \approx 1.87\)
> if you weigh 150 lbs on Earth, you would weigh roughly 280.5 lbs on 1140b
Nonsense. You mean not able to support terrestrial life.
>Helium cannot support life because it is a chemically inert noble gas. It does not form the complex, stable molecular structures (like carbon chains) required for biology. Unlike oxygen, it cannot be used by living organisms for cellular respiration to generate energy, making it an asphyxiant.
However, maybe we are projecting our current understanding of biology and shouldn't rule it out. I'm not a scientist so I have no idea.
Nitrogen being replaced by helium would actually be fine but for the niggling issue that we need nitrates. There are no heliates (?) to compensate. The name doesn’t even make sense… helium is the sole gas to have an ium end like metals- chemically it’s that meaningless what you call it as an ion…it shines elsewhere though.
For biology, it’s a necessary condition that the environment react with it and it reacts to the environment. Over time the two become deeply intertwined through the process of evolution.
It’s hard to see how that kind of evolution will occur if a lot of the environment is nonreactive.
Survival may be plausible though. There’s been some research showing some bacteria can survive in high helium environments. That’s a far cry from proving something like a bacterium can evolve in a helium environment that’s non-reactive though.
So the question becomes: How much of that atmosphere is helium?
The era of ridiculous sounding last words came to an end
An inert element, for that reason is just not suitable for life. It's not a reasoning based on anthropocentricity it's just basic chemistry and mathematics. If things can't assemble together, and combine, and form more complex structures, you can't get life. If you could get life out of simple basic atoms, we would see life everywhere, and we would be creating it everyday in labs. We don't.
Doesnt mean life can't exist there by using other elements, but detecting helium is not increasing the likelihood of finding life there at the very least.
Don't be so open-minded about extra-terrestrial life that your brain falls out.
and blaming Canada.