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Record-Breaking Galaxy Cluster Discovered

nasa.gov

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Re: Record-Breaking Galaxy Cluster Discovered

#21

Post by zamalek »

bwang29 wrote: post #2

NASA is making a lot of "record-breaking" news in the past few weeks and it is increasingly difficult for me to think how these news affect me and my relationship to the Galaxy. I understood many of these discoveries translated to "current science could be wrong". But if counting stars isn't my hobby, what am I supposed to take a way from this and digest the meaning of 11.1B light years distance?

It's basically an experiment that has been running for billions of years. As you go forward in time (closer to earth) you also find more initial setup conditions - almost like scrubbing back and forth in a photographic timeline.

It's an amazing database of real-world physics that we can test our predictions against. These astronomical theories have a habit of trickling down. Consider the impact of having a massive fusion generator in our solar system: fusion energy is something that could have a rather substantial impact on every human being.

Re: Record-Breaking Galaxy Cluster Discovered

#22

Post by adrianratnapala »

honkhonkpants wrote: post #13

I always wondered about these measurements. Excuse me if this is rookie astronomical information. I have read that we gauge the distance through brightness. That is we know how bright such an object should be at the source, and estimate the distance based on actual brightness at the instrument. How do we know it's not just brighter than we believe, instead of being as far away as we believe?

Let's distinguish redshift from (the more murky notion of) distance.

Astronomers usually just think in terms of redshift and might never convert into "X light years from Earth" until they write a press release. Red-shift is measured directly, because we have all kinds of ways of knowing about the spectrum expecte from various things, and we just see the expected pattern shifted.

The calibrarion from red-shift to distance is done by considering the brightness of objects. But here astronomers can just pick and choose those objects for which they have good models.

An example is the type 1a supernova (https://en.wikipedia.org/wiki/Cosmic_distance_ladder#Superno...). These are stars that were actually growing until the tripped over a very specific mass threshold and went nova. Because they all had the same initial mass, they all have the same brightness.

Re: Record-Breaking Galaxy Cluster Discovered

#23

Post by nononosisisi »

flamedoge wrote: post #11
bwang29 wrote: post #2

NASA is making a lot of "record-breaking" news in the past few weeks and it is increasingly difficult for me to think how these news affect me and my relationship to the Galaxy. I understood many of these discoveries translated to "current science could be wrong". But if counting stars isn't my hobby, what am I supposed to take a way from this and digest the meaning of 11.1B light years distance?

That's just how science is. It doesn't need to be driven by a business or human "need".

The drive to satisfy our curiosity is a human need and what drives scientists.

Re: Record-Breaking Galaxy Cluster Discovered

#24

Post by javiramos »

10011100 wrote: post #18
djloche wrote: post #5

Earlier quoted context omitted.

The opening line tells it all for you: "A new record for the most distant galaxy cluster has been set". For reference: https://en.wikipedia.org/wiki/List_of_the_most_distant_astro...

At this scale of time and given the size, age and distance of galaxies, it doesn't really mean anything that will ever change our lives. https://en.wikipedia.org/wiki/Galaxy_cluster We can't go there. Nothing from there will visit us. If the big bang is even an actual thing, it still happened everywhere, whenever. There are lots of galaxies, and they are old and far away.

A classic: http://www.lettersofnote.com/2012/08/why-explore-space.html

Re: Record-Breaking Galaxy Cluster Discovered

#25

Post by kjs3 »

10011100 wrote: post #18
djloche wrote: post #5

Earlier quoted context omitted.

The opening line tells it all for you: "A new record for the most distant galaxy cluster has been set". For reference: https://en.wikipedia.org/wiki/List_of_the_most_distant_astro...

At this scale of time and given the size, age and distance of galaxies, it doesn't really mean anything that will ever change our lives. https://en.wikipedia.org/wiki/Galaxy_cluster We can't go there. Nothing from there will visit us. If the big bang is even an actual thing, it still happened everywhere, whenever. There are lots of galaxies, and they are old and far away.

You must be a joy at parties.

Re: Record-Breaking Galaxy Cluster Discovered

#26

Post by dwarman »

Not "wrong" - just fractally revealed details. What I find amazing here is thatit shows the fractal nature does not only work by looking into ever smaller regions - we also are discovering fractally larger structures exploring in the other scale direction.

Re: Record-Breaking Galaxy Cluster Discovered

#27

Post by flamedoge »

nononosisisi wrote: post #23
flamedoge wrote: post #11

Earlier quoted context omitted.

That's just how science is. It doesn't need to be driven by a business or human "need".

The drive to satisfy our curiosity is a human need and what drives scientists.

To me that is more of a desire than a need, but I digress.

Re: Record-Breaking Galaxy Cluster Discovered

#28

Post by ImTalking »

CapitalistCartr wrote: post #7
ImTalking wrote: post #6

As our instruments get better, are we going to find these clusters further and further out until we hit the supposed age of the universe @ 13.7B years? Then what? When do we start thinking that maybe the models are potentially wrong?

When we have evidence to the contrary. Speculation about what we might find in the future doesn't change anything.

I would say that galaxy clusters forming after only 2.6B years is an indication that our models are already wrong.
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