Artemis - the NASA mission

According to the above link, "Stellar remnant black holes are the astrophysical origin of dark energy".

I've come across the idea of the mentioned "cosmological coupling" before, by which black holes are said to be fundamentally tied to the expansion of the universe.

The new hypothesis of "cosmological coupling" seeks to explain why the universe's black holes appear to be more massive than astrophysicists expected them to be.

Observations of the gravitational waves produced when two black holes collide show that many black holes are up to 2.5 times more massive than was thought to be the norm, and astrophysicists can't explain these results on their current understanding of the formation of black holes.

A paper published in November 2021 proposes that black holes don't only get more massive by merging with each other, but that their masses are somehow "cosmologically coupled" to the expansion of the universe i.e. the more the universe expands, the more massive black holes become!
The extra information in planet10's link is the claim that black holes enclose 'vacuum energy'.

"Vacuum energy" is decribed as a "material that results from squeezing matter as much as possible without breaking Einstein’s equations, thus avoiding a singularity".

With singularities absent, the combined vacuum energy of black holes produced in the deaths of the universe’s first stars is shown to agree with the quantity of dark energy we currently measure in our universe.

The upshot is that there is no need to add anything new to the universe as a source for dark energy - black holes are the dark energy!

Much more information here:
The research was published in the Astrophysical Journal (ApJ).

The Astrophysical Journal is an open access journal devoted to recent developments, discoveries, and theories in astronomy and astrophysics. Publications in ApJ constitute significant new research that is directly relevant to astrophysical applications, whether based on observational results or on theoretical insights or modeling.

Articles in the ApJ are subject to a publication charge and are generally sent to one peer reviewer.

I prefer scientific sources, not sensationalized half baked media.

We could search the ApJ to locate the article(s) in question and possibly eliminate the sensationalism - if we knew what title(s) to search for.
Yes, much more balanced in terms of the conclusions.

The researchers have observed that dormant black holes, like the one in the middle of our Milky Way galaxy, are somehow growing in mass, even though they are not swallowing stars and other nearby material.

In trying to explain that observation, they have come up with pure speculation and hypothesis involving the evolution of black holes.

All surprises me, because I thought Black Holes are a Dark MATTER candidate too.

Yes, how could dark matter black holes gravitationally attract everything towards them while simultaneously driving the universe apart with their dark energy?

Yummy! 🍻:drink:
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I'll be looking up this evening, Steve, at the two brightest planets visible from Earth as they appear so close together.

We have blue skies up here at the moment, so fingers crossed!

To add to the spectacle, the unlit portion of the Moon will glow with earthshine.

I have just been out with the camera! 6PM here. The Fireworks setting seems to do the right things.

Clouds were coming and going but a fine sight: Venus at the bottom was slightly obscured in this shot.

It is very bright.

Conjunction Moon Venus Jupiter 22nd Feb 2023.jpg

It will be interesting to see how it changes over the next 10 days.

Here's the Christmas Conjunction I saw a couple of years back. Jupiter and Saturn.

Conjunction Christmas Eve.jpg

Cold work, this Astronomy! :D
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I forgot about it until your post came in at the same time as my wife reminded me to go out!

Same viewing conditions here. Managed to get a brief, but spectacular view of all three heavenly bodies unobscured by cloud.

You've managed a good photo, Steve. By the time I had set up my telephoto lens, it had totally clouded over! Maybe tomorrow.
Remember the 6 Ps, Galu.

Prior Planning Prevents Pretty (sic) Poor Performance!

I am keen to do further observations tonight, and chances look good after 7.30 PM in Southsea, UK.

Weather 20.00 UK 23-02-2023.jpg

I further improved my efforts last night. This is 6.15 PM and 7.15 PM:

S7 Screenshot from 2023-02-23 02-02-20.jpg

You can see that in a mere hour, the Moon had moved appreciably. Kepler would have predicted it, of course. The ancient Greeks would have figured it out too.

Great subject, Astronomy. And doesn't cost much.
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