Where did the matter that makes up the solar system come from

From what I can find, the solar system was formed from a fragment of a giant molecular cloud about 60 light years across. Where did the cloud come from? Did the cloud form any other stars like proxima centauri?

How does a molecular cloud that large form? Was there some massive star that went supernova that gave birth to the cloud?

We have a third generation star, possibly older. Do we have a rough idea how our solar system got here from the beginning? Was there a first generation star that went nova, then a second generation star that went nova, and our system was formed from the molecules of the second generation stars explosion? What are the lifespans of the earlier stars?

Ever hear of the Big Bang? Lots of material was ejected, and much of it became galaxies, stars and planets.

“Generation” is a little bit of a misnomer with stars; the various different types have lifespans that vary by several orders of magnitude, and the hot bright stars that tend to produce supernovas are among the shortest.

But to answer the question more directly, we know that at least a lot of the material in that cloud was supernova ejecta, because Earth has numerous elements in it heavier than iron, which (until humans started to be able to create them) could only be produced by stellar explosions.

He’s asking about much later. Our star is a lot younger than our galaxy, which in turn is a lot younger than the universe. So you’ve got a galaxy out there. Why did our star form?

Sorry, I misunderstood the question. I thought star formation was fairly well understood these days. Perhaps an astrophysicist will stop by and explain it all to us.

As dolphinboy said, an astrophysicist may reveal something different, but so far as I’m aware, the material which made our solar system is straight from the Big Bang. It didn’t condense into a start, blow up, and then condense again into a solar system.

Where all the stuff that came out of the Big Bang came from, no one knows. My personal guess would be that, short of someone from “the outside” sending a message in to contact us, there’s probably no knowing. I suspect that all the information that one could use to deduce where matter came from was, effectively, destroyed by whatever process created the Big Bang, making it unknowable what came before that point. (Though, hopefully I’m wrong on that point.)

I believe that it’s possible that matter can spontaneously come into being (and sometimes does). So it’s possible that the universe generated a bunch of matter spontaneously, collapsed into a singularity, and then erupted into our current universe. But that still doesn’t answer where the matter “came” from.

I’m not an astrophysicist but you are wrong. The material that makes up our solar system came from a previous star which went supernova. Hence the gold, uranium, etc in our crust. Actually, all the elements heavier than (iirc) lithium have come from previous stars.

so far as I’m aware, the material which made our solar system is straight from the Big Bang.

Nope. TimeWinder had it right. (From Wikipedia) “The majority of atoms produced by the Big Bang were hydrogen, along with helium and traces of lithium. Giant clouds of these primordial elements later coalesced through gravity to form stars and galaxies, and the heavier elements were synthesized either within stars or during supernovae.”

Some of the 'cosmic dust" that made our solar system and our planet came from the ejected remains of super nova explosions, no question about it.


The first stars were almost completely made of Hydrogen. Hydrogen combines to produce Helium and energy, Helium combines to make Carbon or Oxygen and energy … and so on up the Periodic Table until we reach Iron … when Iron is formed it takes energy rather than give it off … bad things happen then and things go boom.

All the heavier elements are formed within supernovae explosions. Since our solar system contains these trans-ferric elements, we can safely say we are made of the remains of supernovae.

I took an astrophysics class in college (lower division).

According to Neil DeGrasse Tyson: “We are, literally and figuratively, star dust.”

Nitpick: Our solar system is third (at least) generation, not 2nd generation. To add confusion, “First generation” stars are called "Population III stars, " 2nd-gen Population II; stars like ours Population I.

Population III stars (1st generation) have essentially no elements but hydrogen and helium. Population II stars have some other elements, but little iron or any element heavier than that. Interesting solar systems like ours, with iron etc., can only arise, I think with Population I stars, with matter resulting from a Population II star going supernova.

(Disclaimer: I’m not a physicist, let alone an astrophysicist. Most of what I think I know I got from Wikipedia or 15 different versions of Modern Physics for Morons.)

He’s just copying Sagan, who in turn swiped it from Joni Mitchell.

This has to be at minimum a 2nd generation star because we have heavy elements in this solar system. I am under the impression that there is a consensus we are a 3rd generation star system, but I have no idea if 3rd is the agreed upon generation or if we are just at minimum 3rd generation (maybe we are 4th or 5th, I don’t know enough about stellar lifespan to say).

So tracing the origins of the matter in our solar system back to the big bang, do we know what happened? This is my crude understanding:

Big bang resulted in large amounts of hydrogen, some of which formed a star (obviously there have been trillions of stars in the universe, I’m just talking about the stars which have created the matter in our solar system). That star went nova, and formed a molecular cloud. That cloud formed a second generation star. After a few billion years that star went supernova and created another molecular cloud 60 light years across. Our current solar system was formed about 5 billion years from that gas cloud.

I’m guessing that is about right, but do we know anything about the timeline (how long did these previous stars last, billions of years, millions, etc?) Do we know if nearby stars like proxima centauri were formed by the same gas cloud that formed our current solar system?

Did the 60 light year across molecular cloud that formed our solar system about 5 billion years ago all come from a single star that went nova?

Nope, more like millions. Although not all of them will be novae or supernovae. You need supernovae to produce elements with atomic number higher than 56 (iron), but even there, you need more than one type or supernova. There are basically two types of SN, core collapse and white dwarf accretion (type Ia). AIUI, current thinking is that certain elements can only be made in one or the other of these two types, although I don’t remember the details.

As for non-novae and supernovae, at the end of a star’s life (one too small to supernova), it goes through a couple red giant phases. During one of these, the Asymptotic giant branch, material is dredged up from the core of the star and later expelled along with the star’s atmosphere at the end of that phase. This material is enriched in low atomic number elements like carbon and oxygen. It may also be the only way certain other elements, such as fluorine, get into the interstellar medium.

As for generations of stars, which idea keeps coming up, this is not really a well-defined thing. The most massive of stars only live about a half million years, while the least massive will live for tens of trillions of years. So don’t try to put too much thought into how many generations of stars there were. Just note that there were a lot of supernovae and a lot of red giants contributing elements to the cloud that formed the solar system.

Yeah, but just think what was created from star dust bunnies!

The short answer is “star barf”.

…who pilfered it from Hoagy.

I have vague memories of our embryonic days as a 3rd gen star dust cloud. You could say I have stardust memories.

Don’t think so. He didn’t claim that “we are star dust”.

BTW, there are some low atomic number elements that are not created in stars. Boron, berylium and some lithium are instead created through cosmic rays (which are actually very high speed protons) hitting interstellar carbon and oxygen atoms. This knocks off some of the protons and neutrons and leaves smaller nuclei. There’s a discussion of it here

wow, cool