Far out cosmology: our sun a very unusual star (Introduction)

by David Turell , Thursday, January 12, 2023, 23:39 (469 days ago) @ David Turell

Many differences:

https://bigthink.com/starts-with-a-bang/sun-typical-star/?utm_campaign=weeklynewsletter...

"Stars come with a variety of properties: mass, color, temperature, ionization, metallicity, age, etc.

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Most stars that exist today formed long ago: ~11 billion years in the past.

"Our Sun, born 4.6 billion years ago, is younger than 85% of all stars.

"Since time immemorial, we’ve wondered, “Is the Sun just a typical star?”

"Our Sun, a G-class star, is more massive than 95% of stars.

"Most stars are lower than ours in metallicity: the fraction of heavy elements present.

"Our Sun has greater enrichment than ~93% of all stars.

"Only half of all stars are “singlets” like our Sun; the other half exist within multi-star systems.

"We’re not typically luminous, either.

"The overall luminosity-to-mass ratio of stars is three times our own.

"Normal, apparently, encompasses an enormous range.

Comment: the age and properties of our sun offer more fine-tuning reasons for the Earth to allow life to appear. The sun and Earth are not near the averages for all other star system. It is obvious we are special