What direct evidence do astronomers have that supports the heavy element formation instars?
A)the presence of technetium in giant star spectra
B)observed elemental abundances
C)gamma-ray emissions from decay of cobalt 56 in supernovae
D)light curves of type-I supernovae
E)All of the above are evidence of this.

Question

Quizplus · Accepted Answer

All of the given options are direct evidence that supports the heavy element formation in stars.

A) The presence of technetium in giant star spectra: Technetium is a short-lived radioactive element that cannot be produced by any known natural process on Earth. However, it has been observed in the spectra of certain red giants. This indicates that technetium must have been created in the star itself and then rapidly transported to the surface. This is evidence that heavy elements are formed in stars.

B) Observed elemental abundances: Through observations of stars and the interstellar medium, astronomers have found that there are many elements heavier than hydrogen and helium present. These heavier elements must have formed in stars as they are not present in the early universe. This is evidence that heavy elements are formed in stars.

C) Gamma-ray emissions from decay of cobalt 56 in supernovae: When a star explodes as a supernova, it releases a vast amount of energy as well as many heavy elements. One of the isotopes produced in supernovae is cobalt-56. It decays into iron-56, releasing gamma-ray photons in the process. This gamma-ray emission has been detected from supernova remnants, providing evidence of heavy element formation in supernovae.

D) Light curves of type-I supernovae: Type-I supernovae occur when a white dwarf star accretes matter from a companion star, causing it to reach a critical mass and explode. The light curves of these supernovae provide information about the elements produced in the explosion. The presence of certain elements, such as nickel and iron, indicates that heavy element formation occurred in the white dwarf before it exploded. The presence of technetium in giant star spectra is direct evidence of heavy element formation in stars. Observed elemental abundances also support the formation of heavy elements in stars. Gamma-ray emissions from decay of cobalt 56 in supernovae indicate the presence of heavy elements. Light curves of type-I supernovae can be used to measure the amount of heavy elements produced in these explosions. Therefore, all of the above are evidence of heavy element formation in stars.

What Direct Evidence Do Astronomers Have That Supports the Heavy