How can you not feel insignificant already?
100 billion stars in our galaxy
10 billion galaxies in the known Universe
At least 15 million times more space in the total Universe
Astronomy & Space Exploration
- Thread starter MrMarcello
- Start date
100 billion stars in our galaxy
10 billion galaxies in the known Universe
At least 15 million times more space in the total Universe
Pretty sure the launch site is in French Guiana, which is on the Atlantic.
Hopefully this one doesn't need glasses 
The images from this will be quite different to Hubble since it can't capture light in the visible spectrum.
The images from this will be quite different to Hubble since it can't capture light in the visible spectrum.
This is really exciting. Huge leaps forward in understanding will be made in a short time.
Oh, there are way more than 10 billion galaxies in the Observable Universe. Hundreds of billions at least.
As far as I know we have no idea of the size of the actual Universe, except that it might be infinite. Unfortunately anything beyond the Observable Universe is unknowable, probably forever (except for the bits that are still 'coming into view', though we're close to the maximum now).
But yeah, all of that makes it difficult to consider us important in the grand scheme of things. I guess the only way is if life happens to be incredibly rare, or even if we're the only ones. Then we're pretty important, I suppose.
You need more proof of this?
Can you explain a bit more on this? Or point me to some good reading material on this
Hubble can capture visible, UV and infrared light whereas JWT only operates in infrared. The images can be translated into nice pictures but they will be different. Left is from Hubble's visible light, right from its infrared camera.
JWT is about 5 times bigger than Hubble so the detail with be incredible.
For the size of the actual Universe, I used this source. The idea that it's "at least" 15 million times larger is based on the curvature of the Universe. I don't think that rules out it being potentially infinite...?
"Observations from the Sloan Digital Sky Survey and the Planck satellite are where we get the best data. They tell us that if the Universe does curve back in on itself and close, the part we can see is so indistinguishable from "uncurved" that it must be at least 250 times the radius of the observable part. This means the unobservable Universe, assuming there's no topological weirdness, must be at least 23 trillion light years in diameter, and contain a volume of space that's over 15 million times as large as the volume we can observe. "
Regarding the number of galaxies in the known Universe, you're right, it's more likely to be in the hundreds of billions.
Thanks for the explanation.Hubble can capture visible, UV and infrared light whereas JWT only operates in infrared. The images can be translated into nice pictures but they will be different. Left is from Hubble's visible light, right from its infrared camera.
JWT is about 5 times bigger than Hubble so the detail with be incredible.
I take it it's still miles off from being able to resolve the shape of a star?
The number of stars in our Milky Way is estimated at up to 200bn. But it often depends on who you listen to.
And based on the current understanding, a similar number of galaxies in what is the observable universe.
That comes to something like 4 X 10 with 120 zeros.
Think that is right. And it is highly likely that with the JWT, that number will increase by a few orders of magnitude.
All that in 13.8bn years from something estimated at the size of an Electron.
Cosmic Inflation, if that happened in a minute fraction of a second must have been so many orders of magnitude faster than the speed of light.
Ah yes, I see what you're saying. I think the consensus today is that the Universe is probably "flat", and not curving in on itself (our outwards)? Or perhaps consensus is the wrong word, maybe it's best to say most common assumption.
I believe this is correct. We have pictures of stars (here's Betelguese), but as far as I know those are taken by large Earth-based telescope arrays. I don't think Hubble or JWT are anywhere near big enough to resolve an actual star. In the future we might put truly massive telescope installations into space, spanning the inner solar system or more (in width).
That was what I had understood, but thought maybe there was a new understanding.
I didn't know there was a "near miss" by another star (just about) entering our solar system 70-80k years ago...
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A newly discovered nearby star with a lengthy catalog designation (later nicknamed for its discoverer, Ralf-Dieter Scholz) seemed almost to be sitting still. Most stars move perceptibly across the sky over the course of a year, as measured in a unit called “arc seconds.” In terms of such “sideways” motion, this one hardly moved at all. Yet the star was only 22 light-years away – quite near to us by galactic standards.
Mamajek knew that could mean only one thing. Either the star was heading straight for us, or it was heading directly away. In this case, the astronomers had obtained measurements of the star’s Doppler shift – the reddening of light if a star is moving away, or a shift toward blue if it’s moving toward us.
“It was screaming away at 80 kilometers per second,” Mamajek recalled. And it didn’t take him long to do the math.
“In less than 15 minutes, we figured out that this star had passed within a light-year of the solar system, 70 or 80 thousand years ago,” he said.
The closest stars to our Sun today are the three in the Alpha Centauri system, about four light-years away. But if there were a star one light-year away, that could very well approach or even intersect with the outermost edge of the Oort Cloud.
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https://exoplanets.nasa.gov/blog/1549/a-passing-star-our-suns-near-miss/
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A newly discovered nearby star with a lengthy catalog designation (later nicknamed for its discoverer, Ralf-Dieter Scholz) seemed almost to be sitting still. Most stars move perceptibly across the sky over the course of a year, as measured in a unit called “arc seconds.” In terms of such “sideways” motion, this one hardly moved at all. Yet the star was only 22 light-years away – quite near to us by galactic standards.
Mamajek knew that could mean only one thing. Either the star was heading straight for us, or it was heading directly away. In this case, the astronomers had obtained measurements of the star’s Doppler shift – the reddening of light if a star is moving away, or a shift toward blue if it’s moving toward us.
“It was screaming away at 80 kilometers per second,” Mamajek recalled. And it didn’t take him long to do the math.
“In less than 15 minutes, we figured out that this star had passed within a light-year of the solar system, 70 or 80 thousand years ago,” he said.
The closest stars to our Sun today are the three in the Alpha Centauri system, about four light-years away. But if there were a star one light-year away, that could very well approach or even intersect with the outermost edge of the Oort Cloud.
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https://exoplanets.nasa.gov/blog/1549/a-passing-star-our-suns-near-miss/
That's incredibly unsurprising. But still sad.
Unusually for NASA, here they are being super critical of Bezos suing over its selection of the bigger, more flexible and cheaper SpaceX lunar Lander.
God I hope not, imagine what we are going to see with something 100x more powerful than Hubble. So excited about this one.
They're annoyed because they selected a Blue Origin engine over a more familiar Aerojet option for the new ULA rocket based on cost and a delivery date of 2019, neither of which happened as promised. 2022 is the earliest possible date though that looks unlikely too. At this point there is talk about scrapping it and giving it all to SpaceX.
Unusual to see NASA basically accuse Blue Origin of risking the manned space programme so they can make a few bucks.
This is a good watch. One of those most intelligent of all intelligent people who have the knack of making incredibly complex things seem simple.
The most complex thing that humans have ever built.
Now that is a big call.
The video is highly informative and yes, the JWST is indeed extremely complex and sophisticated.
But given the timescales, available technology at the time in the 1960s, starting from scratch, landing men on the Moon and returning them safely, I would definitely say that the US/NASA space programme was orders of magnitude more complex and demanding than the JWST.
Just my opinion.
But does that make it less complex? Just because it was easier, made so by technology also made by humans, doesn't make it less complex than something simpler, just because that thing was more difficult to make.
The pyramids were more difficult to build than a skyscraper. That doesn't make them more complex than modern architecture.
Ok. The point I was trying to make was that the US Space programme involved putting a human(s) onto the Moon etc.
And using totally untried technologies, all in less than 10 years after Kennedy famous speech.
Almost every experiment had to be right first time and almost nothing had been tried before and had to be invented.
The JWST is undoubtedly a remarkable feat of engineering. But it doesn't have the same human risks.
Anyway, as I mentioned, just my opinion.
Taken literally it could well be true. Apollo era technology is prehistoric by today's standard, even the ISS is established tech. We could replicate them quite easily in today's world whereas the JWT could not have been built in their time.
And we haven't finished ITER or the upgraded LHC yet.
Interesting video. And to be fair he says ONE OF the most complex.
Understand that. And I would definitely judge the commercial production of Nuclear Fusion energy as a stand alone supreme achievement of humanity.
In my opinion, you ought to judge and particular complexity of a particular achievement based upon the levels of technology at that time. Not necessarily by today's standards.
Replicating the Apollo landings even using today's technology is still some way off.
Eh? Replicating the landings isn't some way off due to any problem with today's technology, but funding, political will and priorities.
Couldnt you create a truly massive telescope with the earth-L2 baseline though? We are going to see some breakthrough stuff with this thing.
I listened to a podcast today and one of the researchers said that she wanted to look for the earliest rays of light in the galaxy and it could be possible to do with the resolution of James Webb telescope. That sounds cool as feck if it remotely revealed anything about creation to go even an inch farther than the big bang hypothesis. They also said this has the resolution to look for signature of gasses like methane in the near galaxies, which could reveal evidence of extra terrestrial life.
Yeah, something like that would be great. Probably coming too, eventually!
Wouldn't it have been a great idea, to name the ship taking William Shatner into space Wednesday the Enterprise?
Missed opportunity there
Missed opportunity there
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"Everybody in the world needs to do this," the Canadian actor told Mr Bezos after landing back on Earth.
hmm
hmm
Let me find that spare 300-thousand quid under the cushion.
SciFi: earth sacrifices life and riches to venture out into space....the final frontier to expand the human race and explore the unknown.
2021: real life Lex Luthor gets 90 year old actor for a promo video on the edge of space and then sprays champagne around as if he's achieved something.
2021: real life Lex Luthor gets 90 year old actor for a promo video on the edge of space and then sprays champagne around as if he's achieved something.
https://www.bbc.co.uk/news/science-environment-59388109
This is so going to explode on take off isn't it
This is so going to explode on take off isn't it