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Comment by delta_p_delta_x | Hacker News Reader

It's a fairly straightforward conclusion that most visible stars are more massive than the Sun. Star mass directly affects the fusion reaction rates at the core, which in turn directly affects the luminosity and the lifetime of the star.

The brightest stars can even shine through dust clouds (or simply emit enough radiation to ionise and dissipate them altogether).

(Space) telescopes can see far dimmer magnitudes than can the human eye at sea level, so more Sun-like stars and red dwarfs show up considerably more easily, given these star types (K and M types) emit strongly in the infrared, which the Earth itself blots out).

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> It's a fairly straightforward conclusion that most visible stars are more massive than the Sun.

I can imagine that scientists have figured out accurate ways to measure the "actual" brightness of stars and including our sun, and maybe in retrospect using some simple insights and tricks, but it's not obviously straightforward at all.

Let's hypothesize that our sun is the most massive star in the galaxy, and what we look at in the sky are the rest of the stars in decreasing order of size, with the largest the most visible. How is it straightforward to conclude that that's not true? And are we declaring Newton's accomplishments straightforward?

Mass spectrometry, classical physics, radio spectrum wizardry, and a whole lot of signals theory

I don't think that actually answer the question. It definitely has an answer, bt just throwing around scientific fields isn't it.

Also, don't you mean stellar spectroscopy? Mass spectrometry is when you fire ions through an electric field to determine their mass-to-charge ratio. Doesn't seem even a little bit applicable to far-away objects.

The real answer is that as our ability to test our current model or knowledge, so does the model evolve. Saying a bunch of stupid science words is just how idiots online attempt to generate consensus to their line of argumentation because they struggle deeply with ontology.

Think about our knowledge of the Earth rotating around the sun vs. the sun rotating around the Earth, or flat Earth vs a spheroid Earth, our models increase in accuracy as their testability increases in tandem.

Thanks for the assist, I don't really know what the answer is so I was hoping someone would iterate on my spike.

Yeah and none of that will be workable if we find out there’s some sort of occluding mechanism or distortion surrounding the solar system. Like saying you will find water because you took a picture of a mirage.

We don’t know. That’s the hypothesis aspect of Scientia.

Our current working hypothesis(es) and theories have not been invalidated so far and thus, they depict the most accurate model we have.

But it’s just a model: data that we get artists to turn into pretty “space” pictures.

If the public had a real understanding of astronomy and space exploration it would neither be seen as interesting or worth funding.

The work that made Hubble famous was built on a slightly earlier discovery by Henrietta Leavitt that variable stars had a relationship between their absolute brightness and their period[0]. These were the early "standard candles" that Hubble used to start sorting out distances to objects within our galaxy and when he first realized that the Andromeda Galaxy is not local to us, but its own separate galaxy. Things have gotten on a lot since then, but the basics of how it was done are extremely approachable, astronomy 101 stuff.

[0]https://en.wikipedia.org/wiki/Period-luminosity_relation

Just to add that that only works for specific types of stars that have regular pulsations. It can be used to infer distances to other types of stars if you have good cause to think that the pulsating star is in the same place as the other stars. This works for clusters and stellar associations, but not for the "field" stars in the galaxy.

> I can imagine that scientists have figured out accurate ways to measure the "actual" brightness of stars

Sure. This is actually pretty simple.

Stars visible with naked eye are relatively close to us. We can measure parallax (https://en.wikipedia.org/wiki/Stellar_parallax) and this gives you the distance to the star directly. Once you know the apparent brightness and the distance you can calculate the actual brightness.

"The Hubble telescope WFC3 now has a precision of 20 to 40 microarcseconds, enabling reliable distance measurements up to 3,066 parsecs (10,000 ly) for a small number of stars."

Vast majority of visible stars fall within couple thousand light years, the only ones that are further are extremely bright, extremely rare and extremely short lived.

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