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An all-sky map of half a million supermassive black holes

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Re: An all-sky map of half a million supermassive black holes

#11

Post by smolder »

mynegation wrote: post #4
purpleflame1257 wrote: post #2

Interesting how anisotropic it is. Naively I would have assumed it would be roughly symmetrical

Interesting indeed but might be an artifact of regions being surveilled and Milky Way disk both containing more easily detectable holes and obscuring some areas with the dust clouds (I am not an astrophysicist or astronomer)

Supermassive black holes are generally at the center of galaxies, like a tiny yolk in an egg. That's not a hard rule. For instance, they can theoretically be ejected and make a mess if a few galaxies collide. But yes, it's harder to detect far away objects when the bulk of our milky way is in the way, making things milky. I suspect there are a lot of black holes back there that we just can't see.

Re: An all-sky map of half a million supermassive black holes

#12

Post by greenleafone7 »

epistasis wrote: post #6

The number of massive maps of the universe in recent years are absoultely fascinating, and have reignited my childhood interest in astronomy and cosmology. These maps consist of a large number of statistical observations derived from images, and that lines up with all the data analysis I've used in the past decades in genomics. (Most DNA sequencing data comes from image analysis, coincidentally!). And the plots I see…

Scary as well though. All those cosmic powers, and here we are, not even ants standing on a hilltop.

Re: An all-sky map of half a million supermassive black holes

#13

Post by xioxox »

We also released the 2nd half sky catalogue of the eROSITA X-ray survey at the same time, for 1.5 years of operations, in collaboration with SDSS. Here is a sky map and 3D plot with redshift: https://www.mpe.mpg.de/8215311/news20260731

This almost doubled the number of known X-ray sources to 2 million.

Re: An all-sky map of half a million supermassive black holes

#14

Post by Insanity »

greenleafone7 wrote: post #12
epistasis wrote: post #6

The number of massive maps of the universe in recent years are absoultely fascinating, and have reignited my childhood interest in astronomy and cosmology. These maps consist of a large number of statistical observations derived from images, and that lines up with all the data analysis I've used in the past decades in genomics. (Most DNA sequencing data comes from image analysis, coincidentally!). And the plots I see…

Scary as well though. All those cosmic powers, and here we are, not even ants standing on a hilltop.

On the flip side of scary, it can put your problems in perspective and offer some kind of solace. I guess it's a bit of both :)

Re: An all-sky map of half a million supermassive black holes

#15

Post by epistasis »

gwerbin wrote: post #8

What are the "gridded" regions in the middle? Is that some kind of measurement artifact?

If you're talking about the purple blotches, that's a map of the regions of the sky that have been targeted for observation. It's not the actual SMBH density.

Re: An all-sky map of half a million supermassive black holes

#16

Post by smolder »

gwerbin wrote: post #9
monocasa wrote: post #3

Earlier quoted context omitted.

I think that's more a result of our incomplete/inconsistent scanning.

On the other hand, the ancients assumed there had to be big continents in the southern and western hemispheres to "balance" the land in their own quadrant. They turned out to be right, but not quite for the reasons they put forth. As a non-cosmologist, I'm unwilling to speculate on what "should" be out there, because my mental model is probably very wrong (keeping in mind that our best models of what's happening out…

Luck of the draw that they weren't lizard people on pangea, making that prediction.

Re: An all-sky map of half a million supermassive black holes

#17

Post by smolder »

Razengan wrote: post #5

Thanks, now I know where not to go

On the bright side, you could live much longer if you went near a black hole. Though, that's according to everyone else's reference frame, not yours. Also, the gravity probably wouldn't feel nice. So, I concur.

Re: An all-sky map of half a million supermassive black holes

#18

Post by jibal »

greenleafone7 wrote: post #12
epistasis wrote: post #6

The number of massive maps of the universe in recent years are absoultely fascinating, and have reignited my childhood interest in astronomy and cosmology. These maps consist of a large number of statistical observations derived from images, and that lines up with all the data analysis I've used in the past decades in genomics. (Most DNA sequencing data comes from image analysis, coincidentally!). And the plots I see…

Scary as well though. All those cosmic powers, and here we are, not even ants standing on a hilltop.

I find this sentiment so bizarre ... scared of what, exactly? There are real threats that people ignore, like rip tides, global warming, RFK Jr., and fascism, but those "cosmic powers" aren't coming to get us.
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