[HN Gopher] Astronomers just discovered the farthest object in t... ___________________________________________________________________ Astronomers just discovered the farthest object in the known universe Author : wglb Score : 44 points Date : 2022-04-08 18:19 UTC (4 hours ago) (HTM) web link (www.livescience.com) (TXT) w3m dump (www.livescience.com) | SkyMarshal wrote: | Key sections: | | _" The researchers discovered HD1 in data collected over 1,200 | hours of observation time using the Subaru Telescope, the VISTA | Telescope, the U.K. Infrared Telescope and the Spitzer Space | Telescope. They were particularly looking at redshift, a | phenomenon in which light waves stretch out or become redder as | an object moves away from the observer. In this case, the | redshift suggested HD1 was extremely distant. | | The researchers found that the red wavelengths were the | equivalent to a galaxy located 13.5 billion light-years away. | | HD1 also seems to be growing at a feverish rate -- about 100 | stars each year, or at least 10 times the rate predicted for | starburst galaxies that are known to produce stars at an | extraordinarily high pace. | | These stars were also more massive, brighter (in ultraviolet | wavelengths) and hotter than younger stars, the researchers | found. | | As such, HD1 could be home to the universe's very first stars, | called Population III stars; if that identity is verified, this | would be the first observation of this type of star, the | researchers said. There's also the possibility that HD1 is a | supermassive black hole with a mass of about 100 million times | that of the sun."_ | | Also a paper on it: https://arxiv.org/abs/2201.00823 | 8bitsrule wrote: | Paper sez: z ~ 13 | thanatos519 wrote: | I can't wait for JWST to look over there! | karmakaze wrote: | Would it be more accurate to say 'oldest' since it's not there as | we're seeing it now? | | I suppose it's all the same in space-time. But what we study | about it is more in relation to the time of the light rather than | the place, so 'oldest' has a more relevant connotation. | rich_sasha wrote: | We have also seen very old objects closer by. | | The Methuselah star is estimated to be 13.7 billion years, in | fact by some estimates older than the universe (which is | clearly somewhat problematic). | | It is a mere 190 light years away. | onlyrealcuzzo wrote: | Is there a physical limit to the resolution we can get from such | absurdly large distances? And if so - is there an equation? | lil_dispaches wrote: | The Big Bang is the diffraction of logic around the perimeter of | the lens on the universe we call Quantum Physics. | marginalia_nu wrote: | That's not even wrong. | ericmay wrote: | Could you expand on what you mean by this? | simonh wrote: | No, sorry, please don't. | Archelaos wrote: | Layperson's question: The article talks about "a possible galaxy | that exists some 13.5 billion light-years from Earth". But isn't | that just the light traveling distance, and the object should | actually be much further away due to the expansion of the | universe? | spindle wrote: | Speaking as someone who used to teach introductory cosmology at | a good university ... your question is not a layperson's | question! (That's a compliment, BTW.) | sph wrote: | To add my dumb question: since the universe expands faster than | light, how is this considered a very far object and not just | that we're looking at something in the past? Is this confusion | of mine between distance and time what physicists mean by | space-time? | simonh wrote: | Well spotted yes, by now that object will be about 45 bn ly | away. The light reaching us from it has only traversed 13.5 bn | ly though. | cygx wrote: | What are you basing the 45 bn ly on? A redshift of z~13 | should correspond to a comoving distance of about 33 bn ly, | whereas 45 bn ly would correspond to z~600. | sdeframond wrote: | Define "now" | | https://en.m.wikipedia.org/wiki/Relativity_of_simultaneity | simonh wrote: | While that's a problem in theory, to moderate accuracy it's | not a practical issue. Most objects in the universe are | roughly at rest relative to the cosmic background radiation | (in other words they don't see it as Doppler shifted in any | particular direction), so we can use that as a common frame | of reference. When we're talking about ballpark integer | billions of years, or even to a few decimal places, that's | easily good enough. | layer8 wrote: | "Light-years" literally _is_ light-traveling distance, though. | :) ___________________________________________________________________ (page generated 2022-04-08 23:01 UTC)