Space/Science — HabitableZone

Space/Science » in reply to What to look for?

Good strategies
ER — (archived)

Unfortunately, the fusion products of stars remain in their cores, where they contribute nothing to their spectral signatures. When we see very old stars, we see mostly H and He in their spectra, even though we know their cores are saturated with "metals" (astronomical jargon for anything that isn't H or He). Stars with lots of metals in their spectra are second or third generation stars, like our sun, and their spectra reflect the chemical composition of the nebulae they were born in. Metals are returned to the interstellar medium in supernova explosions and in the outgassing of planetary nebulae. (More astronomical jargon, planetary nebulae have nothing to do with planets, they are stars that have blown away all their outer layers in their stellar winds.)

There may be other ways though, like the spectral differences between Type I and II supernovae (one is known to occur only in binary systems with mass transfer) but I fear the sought-after variations in fusion products would probably be swamped by the inherent variance of metals due to other causes.

Log in or register to post.

The whole thread (32 posts)