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

sdss.org

31–40 of 44 posts

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

#32
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.

Why are some areas more observed than others then?

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

#33
post #27

Earlier quoted context omitted.

Love how you throw in RFK Jr. His muscular tone is certainly impressive!

I referred to real threats, and he is one. His muscles aren't relevant.

They are if you ever try to take his raw milk away

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

#36

Anyone ever worked with data from SDSS? What have you done with it? I imagine it's a gold mine for university students. I took an astronomy class and was able to plot the largest structures in the universe from their data, which was cool but pretty basic. I've loved astronomy all my life and I've always wondered if there was anything more one person or a small team could do with SDSS data. I took the class in 2010 so…

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

#37
post #35

Woah, cool. Why is the map so uneven? Does this reflect differences in how frequently such objects occur, or does it have to do with how the scanning works?

Various types of 'lumpiness' in the observable universe are huge topics of research.

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

#38
post #13

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.

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

#40

Earlier quoted context omitted.

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 :)

Doing this in my early 20s helped me out of a depression.

The perspective shift is massive.

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