Little Red Dots

You know the James Webb Space Telescope, the JWST, the most powerful eye humanity has ever pointed at the sky? Well...

jwst has been spotting these strange tiny mysterious things called led little red dots hiding deep deep deep in space for a while of course and nobody knew what they are scientists were scratching their heads but now it looks like the secrets of those little red dots might finally be coming out and trust me the answer is mind-blowing then And then, yeah, we're going to zoom all the way out, like really, really far out.

And we're talking about Lanyakea, a supercluster of galaxies so absolutely massive that our entire Milky Way, which is our home, of course, is just a tiny little dot inside of it.

I'll help you picture just how big Lanyakea is.

It is a giant telescope and it's floating in space.

And since it started sending pictures back to Earth in 2022, it has shown us things that we have never seen.

never and I'm telling you again never seen before but here is the thing about web yes it has answered many questions but it has also given us some brand new mysteries and one of the biggest strangest most awkward mysteries and most puzzling mysteries of all I can say scientists have been calling them the little red dots so what are those mysterious little red dots let me paint you a picture right imagine You are looking at a photograph of the very, very, very early universe from the past, okay? And we're talking about a time when the universe was very, very young, much younger than it is today.

And in that photograph, you start to notice tiny, small, compact little objects.

What's your second paper? Right, what's my next paper? Well, third paper.

So my next paper is titled, and it's a long title, so buckle up, A Spectral Framework for Testing the Quasi-Star Hypothesis in Little Red Dots 1, colon, Weighing Little Red Dots by Their Super-Eddington Luminosity Ratios, No Signs of Overmassive Black Holes.

And this is led by Olivia Curtis.

And Olivia is at Pennsylvania State University.

And this seems to be submitted to the AAS set of journals.

So it's been a while, I feel like, since I talked about Little Red Dots.

And that was on purpose because I do talk about them a lot.

And there's so many papers on them that it just isn't right to focus on them.

Later in the show, we'll discuss what you can expect to see in the night sky as October looms.

The moon shows off a new crater, and we have an update on the evolving mystery of the universe's little red dots.

And I need to apologize because I didn't have an episode for you last week.

I was out of the country for nearly a week on vacation and sadly I didn't have time to load up a new episode or even a rerun before I left.

But its arrival high in the evening sky is another sign that autumn observing season is here.

Finally, we have a quick update on a star trail's mystery.

A few weeks ago in episode 121, we explored the strange little red dots that the James Webb Space Telescope has found scattered through the early universe.

We talked about the problem.

That phrase super-Eddington came up in the lead, and it's about to come up again because the second story this week is also about a black hole eating faster than it should be able to, just 11 billion years earlier.

The little red dots.

The little red dots.

And if you've been with us a while, you'll know these have been one of the most irritating things the James Webb Space Telescope has found.

Extremely compact, extremely red, extremely numerous in the early universe.

A heavy seed.

A heavy seed of around a million solar masses, which is roughly 10 times heavier than theory typically expects.

And then those seeds develop dense optically thick disks, so thick that light bounces around inside them, scattering off free electrons on the way out, and that electron scattering smears the hydrogen emission into exactly the broad lines we see in little red dots.

Right.

Astronomers categorize this specific population as little red dots or LRDs.

Catchy name.

Yeah.

And so it gives us a huge, uh, and important constraint on what physically the objects actually are that we're looking at.

So talk me through a bit what that tells us with these little red dots i- in terms of y- you, you can work out their temperature, can you? For example, you can work out their composition?

Yeah.

So the spectra of the little red dots are truly unlike anything we've seen before.

And so what we do learn is we see a few very important features.

So on the one hand, we see almost no UV light, so no blue light.

So it's kind of like the sun, and density is also actually kind of similar to the sun, like the outer parts of the sun.

And so it's something we see in the spectrum.