How the Euclid Telescope will map the Dark Universe 

You are so kind, thank you!

Happy to have you along for the ride!

Thank you, that's so much appreciated!

Mathemagic is the correct medical term and that is why I love this channel so much. He used to work on Hubble so it's like hearing from the people that work on the thing almost.

My pleasure, and thank you for the kind words!

I think this is one of the greatest achievements of humanity. Mapping the universe. This will lay the cornerstone for future science and space travel. We are first to expand humanities observational realm to the almost entire possible-visible universe

Same here!

Yeah, it was a little on the down-low, but I'm glad it's up and running smoothly!

You are so very kind, thank you!

@@LaunchPadAstronomy you have been so kind and amazing from the moment I fell upon a live stream a couple of years ago and instead of making fun of me for not knowing who the guest was, you took a few moments and gave me a quick run down and just suggested I stick around and see how it goes and ask questions if necessary... Maybe not verbatim, but very polite and always kind and responsive since! I try to catch whatever comes out 🍻🌎❤️🚀

Thanks!

Thank you! And it’s one of my favorites as well :)

Wow, thank you, I’m so glad I didn’t mess it up too badly 🙂

Thanks 😁

Thanks man!

Of course it is!!! Why did I say Arizona? Ugh

Thanks!

Yep, I messed that up :(

Yes, but then again this is the field where we call the remnants of dying stars "planetary nebulae" and O & B-type stars "early" and K & M-type stars "late". This is the field where nothing is named correctly!

Not sure, but it’s one of my favorites.

Yeah :(

SMBHs are at the centers of those galaxies in the foreground cluster, but their mass isn't enough to create the lensing we see. For example, the milky way's SMBH, Sag A*, is 4 million solar masses, yet the Milky Way has ~400 billion solar masses worth of stars. The black hole is *tiny* compared to the rest of the galaxy, and doesn't exert enough gravitational pull to keep the rest of the stars in orbit around it, let alone everything else!

​@@LaunchPadAstronomyso the sagA SMBH seeds the central mass that eventually builds and directs the form of the circling spiral galaxy?

Good question. I'm not sure, but if I had to guess they probably went with a design that they knew could survive launch. Besides, they're not going to be looking at stars very much anyways.

@@LaunchPadAstronomy That's a reasonable answer. I would expect a similar response from those who do know, thinking about it.

That's redshift. I should have added that to the graph.

Same reason, actually - so they can keep it cold for the near-infrared work. It's really the best place to put any astronomical telescope.

Flatness is about geometry, not about size. And galaxies (which are not close to each other) expand away from others because the physical space between them expands.

95% of the matter in the universe is in the form of dark matter. But later in the video I quote the composition of the universe using the numbers you cited.

@@LaunchPadAstronomy Please check again. 85% of the matter is dark.

Thanks! I know the impact to astronomy is insignificant compared to the impact to Ukraine but Russia’s invasion does have impacts that go far beyond the war.

​@@LaunchPadAstronomyAbsolutely!

"What does a flat universe mean, though? This flatness isn’t the two-dimensional kind we often encounter in everyday life, but you can envision it with a few analogies. Say you’re standing in one corner of a square room. Walk 10 feet along the wall to the next corner, then turn 90 degrees. Walk another 10 feet and turn 90 degrees again. Do this twice more and you’ll find yourself back where you started - you’ve completed a square. This is the standard Euclidean geometry that we all learned in high school, and if you add one more dimension you get a flat universe. But conducting this experiment on a positively curved space that's representative of a closed universe would create a different outcome. This time, start at Earth's equator and walk to the North Pole. Then, turn 90 degrees and walk back to the equator. Turn 90 degrees once more and walk back to your starting point. In the flat universe example, it took four turns to get back to where you started, but only three in the closed universe example. If you're (understandably) still confused, here's another example: In a flat universe, two rockets flying next to each other will always remain parallel. This is unlike a closed universe, in which the paths of these two rockets will diverge, trek along the curvature of space, and eventually loop around to meet where they started. And in a negatively curved, open universe, the rockets will separate and never cross paths again." m.astronomy.com/news/2021/02/what-shape-is-the-universe

Fair point. I should have clarified that. In a "flat" universe, objects on parallel paths will remain parallel, presumably for eternity as it implies the universe is also infinite. It's a fascinating topic, but it really merits its own video.

@@LaunchPadAstronomy Thank you that clarifies it :)

Russian scientists must eye-rolling, head-shaking and tut-tutting at Putin big time...

Should get a T-shirt that says "Flat Universe Society" 🙂

Way to pick a meaningless nit.