Does the sun really belong in its family? Astronomers get to the bottom of stellar identity crisis

[Admin]

Astronomers have questioned whether the sun fits in with its family of stars. New research finally settles the debate.

Does the sun really belong in its family? Astronomers get to the bottom of stellar identity crisis : Read more

 

[Torbjorn Larsson]

The article is a bit of a hard read since the fact from the press release is dropped, that Doris is a representative of a high metallicity star clustering of "Doris-like stars" analogously to how Sun is a representative for Sun-like stars. So the paper is comparing Sun vs Sunlike stars and Doris vs Dorislike stars and Sunlike stars vs Dorislike stars to get to the metallicity dependence. (Also, there is a repetition in the article: ",,, Doris had a longer period than the sun. And, in fact, we found evidence of a correlation between the rotation period and metallicity." In addition, despite being younger than the sun, Doris rotates more slowly.") The money shot is IMHO the paper figure 7 where Sun with better statistics sits in the center of the magnetic activity and metallicity distributions of the Sunlike star classification.

 

[Helio]

Yep. The first problem I saw was in calling it a "blue star". There are no blue stars that will be the same mass and size as the Sun, even with 2x the metals, no doubt.

Here is an article implying this star is like our yellow star. It's one of the coolest illustrations of our Sun I've seen, though it's demonstrable that the Sun has not a hint of a tint of yellow in it (if seen from space).

Those metals should make a difference in things like the magnetic field. 10 years ago it was reported to have a 7.4 year cycle vs. the Sun's ~ 11 yr. cycle.

I was surprised that the Solar analog - Wikipedia does not list this star (HD 173701) as an analog, nor a solar twin. The latter being a tighter match with Sun. So just how close is this star to the Sun.

It's curious to me to see the solar twin list in Wiki showing that the G3 stars seem to be a better fit for the Sun. What spectrum issues would do that? Mag fields have that Zeeman effect that smear the absorption lines, perhaps, but some of these stars have the same metallicity so why would that be the case?