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What would a 25km resolution of earth look like

Great in depth youtube video on this project: https://www.youtube.com/watch?v=go-50Dpzs20

Wow. 25km resolution of the exoplanet's surface.

Of course, getting the telescope into place, steering it, etc. - that's the hard part.

I wonder about all the extraterrestrial AI swarms that have already imaged earth.

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.

> I hope that aliens build a similarly amazing telescope

I hope they did that eons ago so that I have a chance to see those images in my lifetime!

According to AI, an equivalent would be roughly when Google maps shows you 10mi/20km reference scale.

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.

Well, there is a way to do it slowly, the probe(s) just need to be in a 500AU circular orbit. At that distance power and thrust are an issue, and RTGs seem like a better choice than solar. Certainly, takes longer to get to orbit than fly through a point for a pic, but you would get a lot more pics.

an ort cloud of eye peices comes to mind

> if you were floating in a spacesuit at the same spot you'd also see that resolution (likely highly distorted) with the naked eye

…would you? The lensing would occur right at the apparent surface of the sun.

Science fiction has entertained and inspired millions of people and we should all be grateful for that but it has also distorted what people think space really is.

When you consider the scale of space it becomes pretty understandable why the Milky Way isn't teeming with civilizations sending large amounts of mass all over the galaxy. A realization one comes to despite the facts that it has taken humans a blink of an eye (on a galactic timescale) to go from tools to rockets and the Milky way is billions of years older than the entire history of the Earth.

Seriously even the nearest star is 6,200+ years at Parker probe speed.

It’s highly unlikely we’re ever getting FTL. We should become comfortable with that and let go our fantasies. Let theoretical physicists chug away at this, we should get underway with projects that are possible with known science.

With variations on nuclear propulsion we could plausibly get to up to around 12% the speed of light. At least that's the number quoted for Project Daedalus [1], which is using nuclear fusion for the first stage and nuclear-powered ion engines for the second stage. With the cruder but more realistically achievable right now Project Orion design (riding the shockwaves of nuclear bombs) you could still get to ~3% the speed of light

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

Adding to this:

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.

Universe #23: keep solar systems far enough that they can't make war on each other.

We are looking at 75,000 years. You forgot the %.

Honestly a near millennia long expedition would be very cool, and doesn’t seem too long on the scale of space stuff.

Yeah, if your username is any indication of your age, you've possibly taken much the same trajectory of pessimism that I have. As a youth, I assumed we'd be hitting multiple Cs or bending space time when I was an adult; As an adult I thought we might get a percentage of C and conquer the solar system; Now I realise Just How Much Effort it would be to accomplish much of any value on our own Moon, never mind Mars.

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.

If you could solve propulsion enough to accelerate and decelerate a spaceship at just 1G, you could forget the probe and just send people there. While it would take ~50 years of earth time, it would only take ~7.5 years for the astronauts. They could reach the planet with most of their lives free to go to work studying or even colonizing it.

We cannot design a probe that travels at the speed of light.

> Can we expect that level of commitments from our governments or corporations?

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.

Have you seen our track record of violence and general ignorance? I wouldn’t poke us with a ten light year pole.

Project Hail Mary :)

If we had a probe in orbit around this planet, do we have a way to stream data across 48 light years with any kind of reliability?

Small fusion reactors don't really solve any of the key challenges. You need reaction mass to accelerate, you run out of reaction mass way too quickly even with a magical energy source on board to throw it out the back of the ship really fast.

Interstellar travel is probably not ever going to happen. Even if we have antimatter propulsion (which is still probably not practical even under ideal circumstances), we’re still talking hundreds of years of travel time to get to somewhere like this star.

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.

One of the Voyager probes measured the density of the interstellar vacuum at 80,000 protons (and the same number of electrons) per cubic meter. A proton going through a piece of aluminum foil delivers a roughly constant amount of energy regardless of speed; a relativistic proton will pinch through and carry most of its energy with it.

(No punchline; I just think that's cool. I understand that the real problem is the rare dust grain, not the ubiquitous gas.)

The political challenge of funding a laser program just for research for centuries seems just as daunting - lacking the capability for some self repairing, self healing devices, the automated or (lobster-ai) probe going to stars is just as far away as when Charles Stross first wrote about it in Accelerando some twenty years ago. Given the collapse of political norms, looking back, the decades long research projects of the US space program appear to be soon relics of the past.

I wouldn't bet on and as I understand theory allows a shorter routes. Major caveat is weve never observed them and their existence doesn't guarantee they're traversible.

What's exciting to me is that the existence of such a planet provides fuel for more research into the field.

If humans can't make the trip, what's the point besides maybe satiating curiosity in a few hundred years from now?

No, it doesn't seem very creative to me.

I don't think I've ever sounded so cynical in my life, but something about the way sci-fi fandom bleeds into real science really makes me deeply uncomfortable.

Not just likely easier. Far easier. They're so far apart on any reasonable effort scale that the comparison is basically meaningless.

Try 74 832 years actually.

Note: terrestrial chemistry is no different from chemistry that can occur anywhere, given the right molecules and conditions, and even then it’s a matter of degree.

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.

Well, some years ago helium was a preferred way for suicide. This reflected very bad on the producers of party balloon helium tanks, so they added an amount of oxygen and it was no longer an effective way.

So the question becomes: How much of that atmosphere is helium?

Assuming non terrestrial life needs complex molecules. Which we can't know for sure.

my Cleveland is extremely Brown right now: https://www.airnow.gov/state/?name=ohio

and blaming Canada.

They’re both the same basically now. Different weather, same assholes. Much of the FL natives I know had to flee to cheaper pastures.