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First images from Euclid are in

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Re: First images from Euclid are in

#91

Post by grahamj »

vasco wrote: post #78
lefrenchy wrote: post #63

It's just so crazy to me to see a galaxy 420 million light years away. That is so much time for what we're seeing to have changed. I presume life can form within that window given the right conditions, so to some degree it just feels a bit sad that the distance is so great that we can't actually see what may exist in this moment that far away

In another way it's really cool to be able to "see the past" even if all we see is always the past. At this level it is like a super power. If only some aliens had put a mirror somewhere far so we could see ourselves too. Or multiple mirrors at different distances. With enough mirrors and light bouncing around the size of the universe itself can be a "storage media" of the past with different photons all around carry…

You don't need mirrors, you just need to get in front of the photons. A time machine or warp drive will do :)

Also the past is the only thing you can perceive, there effectively is no now.

Re: First images from Euclid are in

#92

Post by recursive »

frabjoused wrote: post #75
stouset wrote: post #16

Earlier quoted context omitted.

There is zero way to optically resolve an exoplanet’s surface without something like a gravitational lens.

If light is hitting it, can you explain why not?

I don't know much about it, but my guess is that 0* photons from that planet make their way into any given telescope lens in a given day.

Re: First images from Euclid are in

#93

Post by thfuran »

shiroiushi wrote: post #52
bikamonki wrote: post #7

So many solar systems out there, life evolved in many planets for sure. No proof but no doubt.

No, there's only one solar system in the entire universe. There's countless star systems though, but only one of those stars is named Sol. /pedant

You can't know that there's only one named sol by the locals.

Re: First images from Euclid are in

#94

Post by hi_hi »

The other mind boggling part is, we've gone from having a limited, accurate, map of only our immediate solar system, to _this_ in ~270 years.

What knowledge of our universe is hiding behind future technology evolutions?

Re: First images from Euclid are in

#95

Post by thrtythreeforty »

frabjoused wrote: post #75
stouset wrote: post #16

Earlier quoted context omitted.

There is zero way to optically resolve an exoplanet’s surface without something like a gravitational lens.

If light is hitting it, can you explain why not?

The naïve optical instrument will be diffraction limited. The resolving power of a lens, basically how "sharp" the resulting image will be, goes down as you decrease the size of the aperture relative to the focal length (that is, as the f-stop number goes up).

A telescope that could zoom into an exoplanet would have an f value of a kajillion or so.

Re: First images from Euclid are in

#96

Post by SoftTalker »

ants_everywhere wrote: post #27
bikamonki wrote: post #7

So many solar systems out there, life evolved in many planets for sure. No proof but no doubt.

"But where is everybody?" [0] [0] https://en.wikipedia.org/wiki/Fermi_paradox

They are all wondering the same thing. Distances are so vast that the overwhelming probablity is that we'll just never notice each other.

Re: First images from Euclid are in

#97

Post by __turbobrew__ »

geenkeuse wrote: post #30

We still have a long way to go to beat this draw distance, but we are on our way. The day will come when we have "sentient" beings, living in a massive world created by us. And they will ponder the same things as we do now. And we will remain invisible and out of reach, but completely observant, and influential in their world. After all, we wrote the program. And they will study the code and discover their own "natur…

The more I learn about physics the more I am convinced this is a simulation.

In a way our universe is very lazy, at large scales where consciousness exists the universe is coherent, predictable. The smaller you get the lazier and fuzzier the universe gets to save computational work. The actual state of things is only computed on small scales when you measure them. The speed of light puts limits on how far humanity can travel to extend the bounds of the simulation. Maybe the expansion of the universe is yet another hedge at limiting how far human can travel. Also, as things are red shifted due to expansion you can run the simulation of far away places slower due to time dilation.

The speed of light and the plank length are both hard codes to bound computational work. The plank length to bound computation getting too complex in the micro scale and the speed of light to limit computation in the macro scale.

It is also very convenient that the closer we look at things the more we see that under the hood things are discrete which is very convenient for simulating.

Maybe every level of the sim increases the plank length and decreases the speed of light in order to deal with inefficiency of doing a sim within a sim? Maybe at the final level of the sim we end up with the truman show.

Re: First images from Euclid are in

#98

Post by JKCalhoun »

Jun8 wrote: post #90

Watching this is ... hard to find the words to describe it. It's insane! It shows us how mind bogglingly vast the universe is and how we're literally nothing compared to it. Paradoxically, it also makes me feel incredibly potent and capable as a human being in that being this small we can know so much! Your size is to the distance of that distant spiral galaxy (420 Mly - 10e24m) as a neutrino is to you (effective cro…

Small and so brief too.

Re: First images from Euclid are in

#99

Post by mlyle »

xpl wrote: post #46
stouset wrote: post #16

Earlier quoted context omitted.

There is zero way to optically resolve an exoplanet’s surface without something like a gravitational lens.

Can't we build a giant optical interferometer in space by sending multiple telescopes out there?

Possibly, but the challenges to do so are immense. Using the sun as a giant gravitational lens seems much more tractable.

Re: First images from Euclid are in

#100

Post by billti »

caust1c wrote: post #21
ekianjo wrote: post #17

Earlier quoted context omitted.

That's Earth. There is no model to say that life always goes on that way. We just have no clue.

I think there's a pretty compelling argument that could be made that matter assembling itself into conscious beings follows pretty naturally from life itself, given a long enough time horizon and assuming the properties of basic elements holds constant throughout the universe which seems pretty likely.

I’m no physicist/biologist, but I always find it odd when they look for water on other planets to see “if life could exist”.

Sure, maybe that’s a requirement for the type of life we on earth know about, but I don’t see why other elements couldn’t have also formed in just the right way to be able to reproduce, and maybe eventually “think”.

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