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First pictures from Euclid satellite reveal billions of orphan stars

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Re: First pictures from Euclid satellite reveal billions of orphan stars

#111

Post by fragmede »

jhedwards wrote: post #103
renegade-otter wrote: post #99

Earlier quoted context omitted.

People underestimate how dead and hostile the space is to life in general. First of all, you can just swipe most of the available galaxy space off the table because of radiation - the center of the Milky Way, close to our "core" black hole, is just pure hell. This is why we inhabit a remote neighborhood of the galaxy. You can extrapolate that most spiral galaxies are like that and only a small sliver of them are "in…

This doesn't seem like the right calculation to me. Doing some quick lookups, I find that the number of galaxies in the universe is estimated to be between 200 billion and 2 trillion. As for stars in a galaxy, there are around 100 billion stars in the milky way galaxy, so lets go with that. If we guess that only about a quarter of any given galaxy is potentially habitable, that leaves 25 billion possibilities per gal…

Aka Drake's equation, with sufficiently large numbers, gives a decent chance of habitability. We just don't know what the numbers really are. Those big enough numbers with small enough other names make for a low enough number that it might as well be zero since we can't observe or interact with them.

Re: First pictures from Euclid satellite reveal billions of orphan stars

#112

Post by ourmandave »

Euclid is bringing together 14+ countries and damn near every related field.

Warms my little nerd heart.

Euclid Consortium

To date 14 European countries contribute to EC activities (Austria, Belgium, Denmark, Finland, France, Germany, Italy, the Netherlands, Norway, Portugal, Romania, Spain, Switzerland and United Kingdom).

Canada and USA through NASA and few US laboratories as well as few Japanese laboratories are also contributing and members of the Euclid Consortium.

In total, more than 2600 members were or are registered in the EC (status early 2023), of which more than 1000 are researchers in astrophysics, cosmology, theoretical physics, and particle physics.

More than 200 laboratories covering all fields in astrophysics, cosmology, theoretical physics, high energy, particle physics and space science that are relevant for the Euclid missions are contributing to Euclid.

https://www.euclid-ec.org/consortium/about-ec/

Re: First pictures from Euclid satellite reveal billions of orphan stars

#113

Post by jokellum »

drlemonpepper wrote: post #96
GuB-42 wrote: post #93

Earlier quoted context omitted.

If the universe is infinite like we think it is, then there is life somewhere, in fact, there is an infinite number of copies the earth exactly like or own, with a copy of you and me on it. We are just "blinded" by the limits of the observable universe. So, we are almost 100% sure that there is extraterrestrial life somewhere in the universe, but if there is no possible causal relationship between us, what's the poin…

this is such a commonly-repeated fallacy. just because something is infinite, doesn't mean everything is possible. the sequence 1,3,5,7,9,... is infinite, and yet it contains no even numbers. there are many such cases.

In this case, the existence of earth is an even number, so I don't see how this is a fallacy.

Re: First pictures from Euclid satellite reveal billions of orphan stars

#114

Post by czzr »

bongodongobob wrote: post #106
czzr wrote: post #105

Earlier quoted context omitted.

Oxygen doesn’t belong on that list, I think - the earth’s oxygen was made by the first living things.

The didn't make the oxygen, they unlocked it from various molecules and minerals etc. It had to be here first.

True - oxygen is very abundant, though, so its presence is not surprising.

Re: First pictures from Euclid satellite reveal billions of orphan stars

#115

Post by White_Wolf »

renegade-otter wrote: post #99
darkwater wrote: post #86

I really find hard to believe how people can say "well, maybe it's not that easy to have other forms of life in the Universe". I mean, we have a cluster with thousands of galaxies, which make it for millions of stars, 240 MILLION light years away. Which means that there is a 240 million years window in which we are basically blind. Any communication from there will never reach the human race, most probably. Philosoph…

People underestimate how dead and hostile the space is to life in general. First of all, you can just swipe most of the available galaxy space off the table because of radiation - the center of the Milky Way, close to our "core" black hole, is just pure hell. This is why we inhabit a remote neighborhood of the galaxy. You can extrapolate that most spiral galaxies are like that and only a small sliver of them are "in…

You are making a few (?wrong) assumptions here:

- that we are first

- oxygen is needed for all life forms

- the habitable zone that is ideal for us the only one that can give birth to intelligent life

- magnetic field is needed for life to exist/radiation kills off all life

Re: First pictures from Euclid satellite reveal billions of orphan stars

#116

Post by bbor »

cuSetanta wrote: post #17

Always a bit special to see science come from a spacecraft I had the pleasure of working on. Honestly there were a lot of issues during the build of Euclid that I was very glad to not be a part of, but seeing the images coming out of it now is pretty damn impressive. Hope all of the engineers that struggled to get this mission spacebourne can enjoy!

Thanks for sharing a human moment, honestly inspiring to contemplate. I have a few interview questions if you find the interest:

1. What was testing/safety/static checking culture like? I have experience within a NASA software contractor that spent a lot of time and stress on balancing classic “aerospace-y” engineering practices with the more modern ones out of SV, which are paradoxically both more and less rigorous than the old ways across different situations. In other words: in a project like this where “groundbreaking” is expected, how closely did you stick to tradition?

2. I’m dumb and just realized: did they pick Euclid because it’s in the EU??

E: 3. What’s it like to be “accomplished”? Like, more so than any random app ceo or sales consultant or whatever, you have now accomplished what would be many young people’s dream: to help build a spacecraft that’s advancing science significantly. I’m assuming all stress dissolves and any sacrifices resolve into being definitely worth it? Asking for a friend, of course.

Re: First pictures from Euclid satellite reveal billions of orphan stars

#117

Post by layer8 »

darkwater wrote: post #86

I really find hard to believe how people can say "well, maybe it's not that easy to have other forms of life in the Universe". I mean, we have a cluster with thousands of galaxies, which make it for millions of stars, 240 MILLION light years away. Which means that there is a 240 million years window in which we are basically blind. Any communication from there will never reach the human race, most probably. Philosoph…

It’s a game of numbers. There may be 10^n opportunities for life potentially forming, with the average likelihood for life actually forming being 10^-m for each. The question is, is n (much) larger than m, or vice versa? We really have no idea, in particular with regard to m. It doesn’t help if n is 100 when m may be 1000. And the human brain is really bad at estimating such likelihoods.

Re: First pictures from Euclid satellite reveal billions of orphan stars

#118

Post by layer8 »

jokellum wrote: post #113
drlemonpepper wrote: post #96

Earlier quoted context omitted.

this is such a commonly-repeated fallacy. just because something is infinite, doesn't mean everything is possible. the sequence 1,3,5,7,9,... is infinite, and yet it contains no even numbers. there are many such cases.

In this case, the existence of earth is an even number, so I don't see how this is a fallacy.

Take the sequence of prime numbers, with Earth = 2. ;)

Re: First pictures from Euclid satellite reveal billions of orphan stars

#119

Post by NKosmatos »

dwaltrip wrote: post #102
NKosmatos wrote: post #90

Earlier quoted context omitted.

No, their night sky would be more or less like our own. There would be other stars and galaxies visible, it's just that this planet (along with the other planets of this orphan star) would be outside of a galaxy and they would be travelling the universe in the "void" between galaxies. Being outside a galaxy doesn't mean that you have a black night sky, it just means that you're a little bit further away from other st…

I don’t think this is correct. Most of the stars we see in the night sky are close by in our neighborhood of the Milky Way. Being in the void between galaxies, there wouldn’t be many neighboring stars close to the orphan stars. This would make their night sky much emptier to the human eye.

For sure their sky would be a lot lot emptier, but I don't think it would be pitch black.

Re: First pictures from Euclid satellite reveal billions of orphan stars

#120

Post by DrNosferatu »

cuSetanta wrote: post #17

Always a bit special to see science come from a spacecraft I had the pleasure of working on. Honestly there were a lot of issues during the build of Euclid that I was very glad to not be a part of, but seeing the images coming out of it now is pretty damn impressive. Hope all of the engineers that struggled to get this mission spacebourne can enjoy!

Indeed, thanks! Euclidean here too ;)
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