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Student astronomer finds missing galactic matter

phys.org

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Re: Student astronomer finds missing galactic matter

#3

Can’t say I’m surprised. Confirms my opinion that dark matter is just literally that: dark, cold interstellar matter

From the wording of this article it sounds like it’s explicitly talking about missing non-dark matter, which is separate from dark matter. So it wouldn’t ‘confirm’ your opinion.

Re: Student astronomer finds missing galactic matter

#6
post #3

Can’t say I’m surprised. Confirms my opinion that dark matter is just literally that: dark, cold interstellar matter

From the wording of this article it sounds like it’s explicitly talking about missing non-dark matter, which is separate from dark matter. So it wouldn’t ‘confirm’ your opinion.

I'm pretty sure 'dark matter' candidates do include cold baryonic matter, it's just that in large part it's been ruled out due to a lack of observations exactly like the one reported here. The fact that we had not seen it, until now, did not definitely exclude it from the definition of dark matter; it just made it rather unlikely. In the absence of observational evidence, alternative, more exotic theories were developed.

The interesting question is how did this cloud form? One of the reasons, for example, that 'dark matter' can't be cold dead stars is that even if the stars were formed at the dawn of the universe, their remnants would still be warmer than the background temperature of the universe and thus we should be able to see them. Many other 'regular' baryonic sources were ruled out for similar arguments, eg, any process that could have created them would have imparted sufficient energy that we should be able to see it, or it would have been swept up into a star or formed a new star. The article did propose a mechanism, but I wish it went into it in more depth. Figuring out ways to explain the observation could lead to insights we had previously overlooked.

Re: Student astronomer finds missing galactic matter

#8
post #5

Show's again how blind universities are with millions of funding, a stundent has to show them.

Where do you think said student has got training, advice, resources and collaborators from?

Student: literally part of the university.

Re: Student astronomer finds missing galactic matter

#9

Show's again how blind universities are with millions of funding, a stundent has to show them.

Had the university not been funded, the PhD student and the team who came up with the idea may not have attended said university and the discovery would not have been made yet.

In addition, universities often return back much more than they are given in funding, for example, universities in the ' League of European Research Universities' such as the University of Copenhagen return five fold the investment [1].

[1] https://about.ku.dk/facts-figures/value-for-society/

Re: Student astronomer finds missing galactic matter

#10
A few things:

1. This isn’t a “student astronomer” this is a full on doctoral candidate researcher. Give her the authority she deserves.

2. This isn’t dark matter/energy. This is baryonic matter that is really hard to detect. Nor is it all of the missing matter, it’s just a smaller piece of it, proving that our current estimate of baryonic matter _may_ be inaccurate if we can find more of this stuff than we accounted for.

2. This is a really cool method! We’ve known for a long time that our atmosphere has a significant effect on light coming though it. It’s a great idea to extend that to find a sort of “extra-atmosphere”/gas floating around in space.

I’m excited to sit down and read this through to see their methodology. My only worry right now is: a straight line of gas is a little too perfect? Couldn’t this be more than a line, and possibly a more standard cloud (like other existing structures we know about). I ask because stars are pin points and if you’re getting data telling you it’s a line in the X axis, for example, you’ll also need data in the Y axis to prove that it’s not taller.

Really hope we can extend this to find more undetectable matter and get our equations in check.

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