Astronomy

ChatGPT explain like im 5:

Scientists who study space recently discovered something very interesting. They were using a special telescope called the Webb Space Telescope to look at very old light that comes from very far away. They found three tiny dots of light that they think could be something called "dark stars." Dark stars are special because they are powered by something called "dark matter."

Now, dark matter is a kind of stuff that makes up about 27% of the whole universe. It's called "dark" because we can't see it directly. Scientists know that dark matter is there because they can see how it affects other things in space, like how it pulls galaxies together. It's a bit like how you can see the wind blowing through the trees, even if you can't see the wind itself.

Dark stars are different from the stars we see in the sky at night. The stars we see are powered by something called nuclear fusion, which is like a big fire in space. But dark stars are special because they are powered by the collisions of dark matter particles. They are much, much bigger and brighter than normal stars, like our Sun.

The scientists found these three possible dark stars when they were looking at really old light. These stars are very young compared to the rest of the universe, even though they are still very, very old. The scientists think that these dark stars could actually be the reason why supermassive black holes exist in the universe. They also think that dark stars could help explain how galaxies, which are groups of stars, form and change over time.

This discovery is very exciting because it could help us understand more about the universe and how it works. Scientists still have a lot to learn about dark matter and dark stars, but with telescopes like the Webb Space Telescope, we are getting closer to unlocking some of these mysteries.

like how are they able to tell the difference

At the moment it doesn't look like they can. The paper is looking for two things that could make the objects "dark stars". The stars would look like point objects because they would be below JWST's angular resolution. The second is spectroscopic data which the writers don't have:

We note here that the spectra for those four objects, obtained in ref. 28, do not yet confidently identify any spectral lines, as they are too noisy (S/N ∼ 2). Follow-up spectroscopy is required in order to determine the presence of emission/absorption features.

The paper's conclusion summarizes what they are looking for in the lines:

we made predictions for the spectra of those SMDS candidates and suggested smoking gun signatures such as the He II λ1640 absorption line, a feature expected for all SMDSs but not for Pop III/II galaxies. We further note that the spectra of SMDS and early galaxies differ for wavelengths above ∼5 μm, so that future observatories (beyond JWST) might be able to differentiate the two types of objects in this way

EDIT:
I will add from the paper:

There are a set of undetermined parameters that control the formation and evolution of a Dark Star, and ultimately, its observable properties.