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First pictures from Euclid satellite reveal billions of orphan stars

nottingham.ac.uk

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

#101

Post by whimsicalism »

alenrozac wrote: post #74
whimsicalism wrote: post #28

Earlier quoted context omitted.

almost all scientific writing i can find from people in portugal uses the short scale. english formal communication has standardized around the short scale

All scientific writing in Slovenia uses long scale. I've heard it being used in EU institutions too.

> All scientific writing in Slovenia uses long scale. I've heard it being used in EU institutions too.

I am able to easily find plenty of Slovenian academics using short scale in their scientific writing. Remember, English is standard for scientific writing and publishing in international journals. I have yet to find a single one using the long-scale, actually.

https://link.aps.org/accepted/10.1103/PhysRevD.97.123540 https://iopscience.iop.org/article/10.3847/1538-3881/abe6a7/... https://link.springer.com/content/pdf/10.1186/s40294-016-001...

> observations by cataloging positions and redshifts of billions of galaxies in the next decade > and the configuration is stable over billions of years. > (networks having up to a billion of vertices; there is no limit—except the memory size—on the number of lines

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

#102

Post by dwaltrip »

NKosmatos wrote: post #90
floatrock wrote: post #87

So an orphan star is one that's been ejected from its galaxy. If one of those stars had a planet with something capable of "gazing up at the night sky", does that mean their sky would be empty compared to our own?

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.

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

#103

Post by jhedwards »

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…

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 galaxy. If we go with that and a middling estimate for the number of galaxies then we have maybe (25 billion * 1 trillion) stars, which is a number so big I don't even know how to say or comprehend it.

Even if we take an extremely conservative view that each galaxy only has at most 25 stars with potentially habitable planets (cutting the 1/4 galaxy estimate down by a factor of one BILLION) then we are still left with 25 trillion possibilities, which seems like a pretty good chance to me.

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

#104

Post by lowbloodsugar »

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…

Space... is big. Really big. You just won't believe how vastly hugely mindbogglingly big it is...

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

#105

Post by czzr »

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…

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

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

#106

Post by bongodongobob »

czzr wrote: post #105
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…

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.

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

#107

Post by 0xfae »

mr_toad wrote: post #52
outworlder wrote: post #44

Earlier quoted context omitted.

At some point, given the universe's expansion, galaxies will be moving away so fast that the observable universe will be just one galaxy. Already, the effective rate from galaxies far away is actually faster than the speed of light. Even at light speeds, we cannot reach 94% of them as we would never catch up if we left today. In cosmic scales of many billions of years, observers on every galaxy will eventually think…

The galaxies in our local group are gravitationally bound.

Right, but isn't the expansion increasing? So if they don't merge into one big galaxy at some point the expansion would out run gravity?

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

#108

Post by greiskul »

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.

But I don't think there is anything special on there being oxygen in the cloud of gas that formed the solar system. The distribution of elements following a supernova probably follows some law, and oxygen is low enough on the periodic table that probably quite a bit of it is expected.

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

#109

Post by whimsicalism »

Tor3 wrote: post #61
whimsicalism wrote: post #14

Earlier quoted context omitted.

my understanding is the long scale has largely died out think it is more than permissible to use what is scientifically standard (trillion = 10^12)

Died out in English . Not in other languages where long scale was and is used, that hasn't changed at all. I'm not aware of any other language shifting from long scale to short scale (for languages traditionally using long scale).

think it is also dying out among many other languages like portuguese

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

#110

Post by irrational »

throwaway765123 wrote: post #88
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…

"I'll tell you one thing about the universe, though. The universe is a pretty big place. It's bigger than anything anyone has ever dreamed of before. So if it's just us... seems like an awful waste of space. Right?" -- Contact (1997)

Waste of space seems like a poor phrase. It seems to imply it should be used by intelligent life, and if it isn't, then it's a waste.
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