Scientists found a Star older than the universe and don't know how to explain it

[E_T]

The Beginning of the article:
Baffling mystery: Star that’s older than the universe
It’s something that shouldn’t be possible. Scientists have been left baffled by a star that appears to be older than the universe itself. 

Astronomers are stumped over a star that appears to be older than the universe.
So how is that possible? That’s the question that an international conference in California attempted to answer.
But instead of solving the mystery, theorists are now questioning whether there is something wrong with the current scientific model of the universe — based on Einstein’s famous theories.




The Article is here:
https://www.news.com.au/technology/science/space/baffling-mystery-star-thats-older-than-the-universe/news-story/be71380233d379dad804bd599f8ea4c6

Comments?

[Lorizael]

As far as I can tell, the age estimate given in that article comes from this 2013 paper. It doesn't seem there's any new data on it, just this conference (where the star's perplexing age was one topic of discussion). So, for a little context, this star has been known about for awhile, and one previous, less precise estimate of its age was even older (16 bya!). But the 2013 paper used Hubble observations to pin the age down to 14.5 billion years old, +/- 0.8 billion years. I don't think this means we have to go back to the drawing board on Einstein's theories, though. From the paper's abstract:

Within the errors, the age of HD 140283 does not conflict with the age of the Universe, 13.77 +/- 0.06 Gyr, based on the microwave background and Hubble constant, but it must have formed soon after the big bang.

So the error in the star's age is big enough (5%) that it's not hard to believe it really is younger than the universe, and the error in the universe's estimate is actually smaller (.04%). How do we have a more precise estimate of the age of the universe than of a single star? Because a star is much more complicated than the universe. Just to give you a taste of that complication, here's another excerpt from the paper:

To determine the age of HD 140283, we employed evolutionary tracks and isochrones computed using the current version of the University of Victoria code (VandenBerg et al. 2012), with an adopted helium abundance by mass of Y = 0.250, slightly above recent estimates of the primordial He abundance, Y0 = 0.2486 (Cyburt, Fields, & Olive 2008). The Victoria models take into account current values for nuclear-reaction rates (see §§1–2), and include the diffusive settling of helium. Diffusion of elements heavier than He is not treated, apart from the small adjustment to [Fe/H] = −2.3 described above, but the effect of this neglect on derived ages is very small.

This goes on for a few more paragraphs. I'm just trying to get across that there are a lot of variables at play here. The basic idea is that they want to match this star's temperature, composition, and brightness (the last being what Hubble measured/determined precisely) with stars of a particular age modeled via computer.

By comparison, this is how you measure the age of the universe: figure out the expansion rate over time (through measurements of distance and recession velocity), then work back to when the universe's size was 0; or stare at the cosmic microwave background, figure out its current temperature, then work back to when it was hotter. Don't get me wrong--these are complicated--but in each case there's basically a single, simple equation (derived from physics), and all that's required is to plug in the right numbers (which come from a huuuuge number of observations that can all be averaged together).

So I would bet we have the age of the star wrong rather than the age of the universe. We'll see. Maybe Gaia can give us an even more precise distance measurement to the star.

[E_T]

Oh, just to let ya'll know, Dale had posted the link for this article over in the WPC Discord Chat channel, I just reposted it here...