Cosmic rays formed three elements - how exactly did that happen?
Small and large stars formed four essential organic elements - Carbon, Nitrogen, Oxygen, Sulfur.
I thought most small stars in the universe were still burning?
Only large stars formed another essential organic element - phosphorus. Are those large stars still burning?
How do you get distribution of organic elements from small and large stars without a supernova?
Cosmic rays formed three elements - how exactly did that happen?
See:
Nucleosynthesis
https://en.wikipedia.org/wiki/Nucleosynthesis
“Small and large stars formed four essential organic elements - Carbon, Nitrogen, Oxygen, Sulfur.”
Some of the most important characteristics of a star depends upon which elements were included in the formation of the star and the total mass of the star. The smaller stars tend to be more stable, with some special exceptions, and have very long life spans. Once a star acquires to much mass, its stellar evolution results in far shorter life spans that result in its disintegration in a supernova or hypernova explosion. The remnant after the explosion may end up as a white dwarf star, neutron star, or worse. The gas and dust expanding outwards into interstellar space forms a cloud known as a nebula. New stars, planets, and other bodies condense out of the nebula due to gravity, light pressure, electrostatic forces, and more. See:
Stellar evolution
https://en.wikipedia.org/wiki/Stellar_evolution
“I thought most small stars in the universe were still burning?”
Usually, assuming an accident has not befallen the star, such as a collision, being consumed by a companion star, or falling into a black hole. Some white dwarfs can become a thermal runaway due to a companion star and explode into a supernova.
“Only large stars formed another essential organic element - phosphorus. Are those large stars still burning?”
It depends upon when they were formed. A star with 60 Solar masses of matter self destructs when it explodes in a supernova in only 3 million years after its formation. A star with 3 Solar masses of matter will self destruct in a supernova in 370 million years. A star with 1 Solar mass has a life span of 10 billion years. smaller stars may last far longer than 10 billion years.
“How do you get distribution of organic elements from small and large stars without a supernova?”
Small amounts are emitted from the star in the stellar winds. The bulk of such matter is distributed by supernovae, hypernovae, and perhaps by the gases streaming out from the poles of a black hole, like those found in the central regions of a galaxy.