
Wow!
Also Wow!
A pint or ten for all those involved.
PS - I'm getting a flashback to the late 70's\early 80's opening titles of Doctor Who.
On Monday, NASA released its first image from the James Webb Space Telescope, or JWST, providing the sharpest and deepest glimpse yet of distant galaxies from the very early universe. The telescope blasted off from Earth at the end of December, and about a month later the probe arrived at its new home about a million miles …
This image, like the Hubble Deep Field image, stuns me when I think about it and they point out how insignificant we are.
As Douglas Adams said:
“Space is big. Really big. You just won’t believe how vastly, hugely, mindbogglingly big it is."
My mind is boggled. I'll send the boffins a pint (but I'm keeping my towel).
N.B. More images tomorrow.
"you may think it's a long way down the street to the chemist, but listen!"
Honestly tho, my mind is really struggling to process this image. It's too big. Everything is too big. That's an almost imperceptible speck in the night sky and it contains more... everything... than it's even possible to imagine.
Humans were not built to handle this sort of scale. I feel awe and despair in equal measure. If this fails to move anyone, they just didn't grasp the reality of what they're looking at.
"Humans were not built to handle this sort of scale. I feel awe and despair in equal measure. If this fails to move anyone, they just didn't grasp the reality of what they're looking at."
Oh, we do have the capacity. For a very, very short time. But as Dr Who said of Humans, they have an infinite capacity to forget and block anything extraordinary :-)
"Light reflected from this mirror is refocused by a tiny secondary mirror, just 0.74 metres in diameter"
0.79m (near enough 31") is hardly "tiny" ... ask anyone who has ground, polished, silvered & mounted a six or eight inch mirror. I wonder how many ElReg commentards remember the excitement of receiving the box from Edmund Scientific labeled GLASS—FRAGILE.
A beer for the boffins ... and anyone else interested.
We already knew the Universe was very big, but with JWST it has become ten times larger still!!
Makes me wonder: there just has to be other life out there. However, we might never be able to contact or reach them if they're in another Galaxy. Also, life could've evolved millions of years ago, flourished and then extinguished.
...chances of life existing outside our solar system: 100%...
Seeing how quickly simple life emerged on Earth, pretty much as soon as it was cool and wet enough for simple organisms such as algae and PE teachers to thrive, they did.
The change from pond scum to multi-celled took a very long time and that step is less certain so while the galaxy is probably teeming with life, there's probably very little we could recognize as intelligent.
Also there's stellar environments to consider, out here in the unfashionable end of the western spiral arm it's pretty quiet, closer to the core star are a lot closer together meaning planetary orbits can and will be disturbed by passing stars, this is catastrophic for most life forms so probably less than half of the galaxy can sustain planets with life long enough to develop beyond pond scum..
Even at "half", that is between 50 and 200 milliard stars, in the Milky Way alone. And there are a lot of galaxies in that picture.
I gotta agree with A Non e-mouse on this one: An almost certainty of intelligent life, and a near certainty of never being able to contact it, barring a significant shift in our understanding of physics.
Cosmology says it's pretty damn near certain that there's not only other intelligent life in the universe, there's other intelligent life that's indistinguishable from us.
WMAP showed that our Hubble volume is pretty damn flat – the curvature is small. So unless our Hubble volume is unusual in the universe as a whole, the universe is a lot bigger than just our Hubble volume. Probability suggests our Hubble volume is unlikely to be special. So there's reason to assume (it's untestable, assuming you want to keep causality intact) that the universe includes a great many times our Hubble volume, containing a similar arrangement of matter.
And if we assume that physics outside our Hubble volume are consistent with what's in our Hubble volume, then that matter will similarly be grouped into star systems and galaxies and so forth.
There are only so many stable arrangements for protons. Given a really big universe with a lot of matter and consistent physics, those arrangements are going to repeat. A lot.
Of course, even communicating with anyone outside our solar system, even within our part of the Milky Way, is a pretty difficult proposition, given the delays (again, assuming causality is preserved, which I for one would prefer) and the various engineering challenges. So all but a vanishingly small fraction of the possible intelligent life out there will forever remain hypothetical.
"even with sub-light speed propulsion it would take the Human race less than a couple thousand years to populate the entire Milky Way galaxy."
Neat trick, seeing as it takes light somewhere around 180,000 years to cross the galaxy. From Earth's position on the inner edge of the Orion Arm, the furthest reaches of our home galaxy are ~120,000 light years away ... but to get there from here we'd have to take a rather large detour around the Galactic Center (at least until the demolition and rebuilding slows down a trifle).
Sadly it is entirely possible for an infinite system to have less than 1 probability of something that is theoretically possible. Mathematics has many examples of infinite summations that are finite. The sum of the reciprocal squares of the positive integers is finite, if the probability that each of your monkeys has a one trillionth times the reciprocal of their number squared probability of writing the works of Shakespeare, then even an infinite number of monkeys would have a tiny chance of writing them, but each would have positive probability.
As far as we know, life on Earth is unique and very precious, it would be nice if we could treat the biosphere accordingly.
Am very aware that infinite sums can be finite: am mathematician. Indeed this is one such case: divide universe into hubble volumes, chance of life in each is c, chance in n is infinite number of hubble volumes ... chance is 1, unless c is 0 which we know it is not.
what you are missing is homogeneity (one of implications of cosmological principle). All these volumes are the same, have the same laws of physics same amount of matter. You keep throwing the dice of arrangements of that matter you will get life with nonzero probability in each one.
yes cosmological principle is principle ie assumption. So is flatness (rather than just approximate flatness), then spatial infiniteness and blah. But given those assumptions probability is in fact 1. See comments by Michael Wojcik who goes into some detail.
(Of course most of it will be causally disconnected from us, and none of this means we should decide Earth does not matter.)
The problem is that we are using a mathematical model (probability theory) to analyse reality. Remember that the model is not reality, it is just a model, and infinities and infinitesimals are tricky. Yes, it is certainly possible that in an infinite universe divided into large volumes each with matter (galaxies, stars, dust, gas, planets etc.) we would assess each as having a non-zero probability of containing intelligent life, but there is also the chance that none of them, apart from our own, does. Statistical models are probabilities, not necessarily reality.
I just hope that if there are aliens out there they are doing a better job of looking after each other and their habitation than we are.
(Alien icon, obvs.)
Yes, all of physics is mathematical model.
But if you can establish a finite (no need for infinitesimals or any non standard number system) lower bound for the probability of life in some volume, or equivalently a finite lower bound for the probability density over some spacelike surface, then in an infinite homogeneous universe (so assuming flatness, no weird global topology, cosmological principle, all as I said earlier) then probability of life is 1. Not 'approximately 1', 1.
And it is easy to establish such a finite lower bound in fact: simply compute the probability of life spontaneously arising due to quantum effects (this is related to Boltzmann brain idea). This is very small but it is finite. Real bound will presumably be far higher but we do not need it: we can just use this one.
I am done here now as it seems increasingly you are arguing from some weird philosophical position and I have no time for those, at all. I am scientist (well, mathematician) I do science not silly word games.
"life could've evolved millions of years ago, flourished and then extinguished"
Some of the very stars that show in the image may indeed no longer exist - we're talking billions of light years distances here. That's an interesting if not often mentioned feature of astronomy - observations of star fields are not temporally distinct.
It can be argued that "no longer" doesn't even make epistemological sense for things like this. We can't have any interactions with those objects faster than light, so their existence "now" relative to a frame of reference based on Earth is in a certain sense irrelevant. What we're interacting with is the light they generated that reached us; whether those objects still exist "now" has no material consequences for us.
Of course, the lifetimes of stars and galaxies and other astronomical objects are questions worthy of research and analysis, for understanding how the universe works. But for a specific object it's the light that's here, and not the matter that's there, which matters to us.
We can propose thought experiments like "if you could instantaneously be transported to the spot that light originated from, make an observation, and then instantaneously be transported back here...". But 1) that galaxy, if it still exists, wouldn't be in the same place "now" relative to Earth; and 2) this instantaneous back-and-forth could lead to temporal paradoxes and causality violations, so we're already in weird and dubious territory.
(OK, it's hard to see how you could create a meaningful causality violation with just this sort of single-back-and-forth between two very distant points in space. But it points to how this sort of thought experiment is already on thin ice.)
For long-distance observations, space and time are inseparable, which makes simultaneity a concept of questionable utility.
I saw somewhere that the age of that galactic cluster is 4.6 billion years. About the age of the solar system, give or take a hundred million or two.
So there may easily be life there now. As for the epoch when that light began its journey to us there is still plenty of time from the big bang some 13 billion years back.