The solar system we live in is believed to come from a large cloud that condensed into the Sun and planets. It is believed to be about 5 billion years old. The galaxy we live in is believed to be over 10 billion years old having condensed from the BB.

We know from studying Supernovae that all the elements heavir than iron come from these explosive stars. This means that prior to our solar system forming there existed a star at or near our radius from the galactic center that exploded as a superova. This had to have happened because our own little planet (and others in our solar system) contain many heavy elements.

Medium mass stars result in white dwarfs after they explode. High mass stars result in Black Holes. Where is the white dwarf? Where is the Black Hole? If our planet formed as part of the Sun and its system then the supernova remnant should still be here.

Could it be that our planet formed in the cloud of another supernova explosion sending it out into space until it was captured by our Sun?

The mystery in this is how could we have heavy elements if we condensed from a cloud that had to be created from a supernova when there is no remnant?

Any thoughts?

Cheers,

BQ 

 

brooksquest:

... We know from studying Supernovae that all the elements heavir than iron come from these explosive stars. This means that prior to our solar system forming there existed a star at or near our radius from the galactic center that exploded as a superova. This had to have happened because our own little planet (and others in our solar system) contain many heavy elements.

It is, indeed, thought that our protosolar nebula was "seeded" by one or more nearby supernovae.

Medium mass stars result in white dwarfs after they explode. High mass stars result in Black Holes. Where is the white dwarf? Where is the Black Hole? If our planet formed as part of the Sun and its system then the supernova remnant should still be here.

There are many white dwarf stars observed in the Milky Way. I don't know how many are "near enough" to qualify as the stars you seek, but it's an interesting point I'll look into. I think the nearest one to us is a few light years away in the direction of Eridanus. Candidate stars would generally share our proper motion if they condensed from the same, or very nearby, protosolar nebulae.

One theory about why some planetary nebulae have wasp-waisted shapes is that the originating star was part of a close binary pair and that the collapse of the nebula-forming component triggered the violent expulsion of both original stars from the vicinity.

Planetary nebulae do not have cosmologically long lifetimes. They dissipate over periods of tens of thousands, to hundreds of thousands, of years as opposed to the billions of years of most stellar lifetimes. If these nebulae are in the vicinity of other stars -- particularly massive young stars -- then solar winds from their neighbors can hasten the dissipation.

Could it be that our planet formed in the cloud of another supernova explosion sending it out into space until it was captured by our Sun?

I'd say that might be possible, but is a whole lot less likely than that it simply coalesced from the same cloud as the Sun and other planets. Meteoriticists look at oxygen-isotope ratios in meteorites and compare them to Earth rocks and Moon rocks (plus some meteorites believed to have come from Mars and specific asteroids -- Vesta is one "parent body" of meteorites) to determine what they have in common. There is an overall commonality, and in some cases very specific 'family" relationships. This leads meteoriticists to accept the protoplanetary disc scenario of Solar System formation.

The mystery in this is how could we have heavy elements if we condensed from a cloud that had to be created from a supernova when there is no remnant?

There are lots of remnants. Whether any fit the "nearby" scenario you seem to envision is an open question at the moment. I would have to look into that more to find out. I don't know, for example, where "here" was 4.5 billion years ago, versus where "there" was (for the remnants) at that time -- assuming remnants have such lifetimes. They do not appear to have such lifetimes.

Wolf-Rayet stars have prodigious stellar winds. One prominent scenario of Solar System formation is that once a star "lights up" its stellar wind blows away most of the as-yet-uncondensed protoplanetary cloud.

I'd add one tidbit you may not be aware of: When you look at what are considered by meteoriticists to be the oldest relics of the protoplanetary disc (certain classes of meteorites and inclusions called CAIs in them) you find their chemical composition is very nearly an exact match to the Sun, their silicates are all found in great quantities in terrestrial rocks (there are no "surprise" minerals), and the only "strange" material to be found in them is called IDPs (interplanetary/interstellar dust particles). Given the content of the IDPs, they must have come from supernovae, or have been seeded by them. There is quite a bit of this stuff up there: hundreds of millions of tons of it spirals into the Sun annually. It is thought it is continuously being refreshed in the inner solar system by comets, whose bright tails spread it along the plane of the Solar System (where, incidentally, these particles can be observed en masse as the Zodiacal Light). IDPs captured magnetically from sea sediments, and by from the stratosphere by high-flying research aircraft, are identical those those in carbonaceous chondrite meteorites.

 When a high mass star goes Supernova, does it blow off its shell at escape velocity where the shell is no longer held gravitationally by the remnant? If this were the case then two or more converging shells might contain enough matter to form our solar system. I think this would also give us a relatively close Black Hole somewhere around here. We do know that high mass stars don't last billions of years so if they were involved then there was plenty of time for the solar system to form 5 billion or so years after the galactic birth. The closest black hole found is about 5000 ly distant. (is that correct?)

It would take more than 3 medium star shells to give us enough mass to form our solar system. I wonder if white dwarfs can re-light if they take on enough fuel (dark matter etc...) The parent stars would live billions of years so unless the Milky Way is much older than we think I find this scenario less likely.

Do active galaxy jets contain any heavy elements? Quasar jets?

Anyway, I thought this was interesting to discuss because of the heavy element/super-nova link. The only solar system formation scenarios I have read about only mentioned condensing from a cloud but did not mention where the cloud came from. Perhaps other references include more about it.

Cheers,

BQ 

 

 

brooksquest:

 When a high mass star goes Supernova, does it blow off its shell at escape velocity where the shell is no longer held gravitationally by the remnant?

There are at least three scenarios involved:

•  Depending on the type of supernova, other events precede the implosion/explosion and in some cases the stars shrink in stages that are long enough to allow outer shells to escape on their own.
• At the supernova event stage, there are blast and shock-wave effects, and for polar areas of the star there are jet effects. Each of these would act to accelerate parts of the remnants to high velocities away from the star/BH.
• Remnant matter orbiting near enough to the event horizon (parts of the original star's atmosphere near the (new) event horizon's radius might not escape being trapped, and would thus fall in.

... The closest black hole found is about 5000 ly distant. (is that correct?)

I do not know. Good question.

It would take more than 3 medium star shells to give us enough mass to form our solar system.

Where do you get that idea? I know that the Sun contains more than 98% of the mass of our Solar System. Since some mass will be lost from the original star during the supernova event, it would probably take at least several stars' worth of supernova remnant material to form a cloud large enough to spawn another star and planetary system, but I don't know how to estimate how many it would take. Some stars which normally would form a supernova may collapse asymmetrically and lose most of their mass to remnants.

But there is no reason to suppose that supernovae are the primary source of interstellar clouds.

Furthermore, most of the mass of the Solar System (e.g., the Sun) is lighter elements -- not supernova material.

I wonder if white dwarfs can re-light if they take on enough fuel (dark matter etc...)

There are weird things like recurrent novae, and Type I supernovae, which involve infalling matter touching off fusion flashes (and explosions) on white dwarf stars. I'm not aware of a model for permanently relighting a dwarf star (you'd have to overcome the tremendous pressure of the degenerate state of the neutron material of the dwarf.

... Do active galaxy jets contain any heavy elements? Quasar jets?

I don't think so. I can't remember reading about anything other than relativistic-velocity subatomic particles in these jets. A relativistic particle must be extremely low-mass, I think. I'm no expert on that topic, however.

Anyway, I thought this was interesting to discuss because of the heavy element/super-nova link. The only solar system formation scenarios I have read about only mentioned condensing from a cloud but did not mention where the cloud came from. Perhaps other references include more about it.

The model I most commonly find discussed in textbooks is the one which has the protoplanetary disc forming from the same molecular cloud as the parent star, and at roughly the same time. I think there is a general consensus that there is a lot of recycling happening in the universe, and that there was more of it going on at earlier epochs.

In the 1970s and 1980s, this was a hotly-researched topic as Planetary Geology became a discipline in its own right during the Apollo data analysis and planetary exploration spacecraft mission era. It has recently heated up again (late 1990s) due to advances in meteoritics and the analysis if meteoritic material. Now that we have more physical samples of "stardust" and cometary particles, there will be many new articles published in short order.

"But there is no reason to suppose that supernovae are the primary source of interstellar clouds."

Why would you think this is true? If there are any heavy elements in the intersteller clouds then they had to come from a supernova (or many). If the clouds came from BB leftovers then all the galaxies would be more or less the same age, which we know isn't true. Not sure if you thought this one through.  

"Furthermore, most of the mass of the Solar System (e.g., the Sun) is lighter elements -- not supernova material."

Most of the mass of the universe is unknown. Most of the mass of the observable universe is lighter elements. Heavy elements are believed to only come from supernovae and not from any other source. If heavy elements are present in dark matter then we may have a very old universe indeed.

Anyway, this is very interesting and I will read more on it to find out more about it.

Cheers, 

BQ 

OK, a couple of comments.

From one of the earlier posts ... the nearest BH I could find listed is about 3,500 ly distant, so your estimate was close enough.

brooksquest:

"But there is no reason to suppose that supernovae are the primary source of interstellar clouds."

Why would you think this is true? If there are any heavy elements in the intersteller clouds then they had to come from a supernova (or many).

The BBT and current thinking on nucleosynthesis is that all heavy elements are forged in stars. However, I am not aware of any statistical estimates based in observational research that shows the different percentages of matter contributed by outflow from Wolf-Rayet stars (though recent research indicates they are much more common than was earlier thought), planetary nebulae formed by the collapse of average stars (like the Sun, which constitute the bulk of stars in the universe, according to current models of stellar evolution), recurrent novae, "regular" novae, supernovae, and hypernovae. In other words, somewhere back in time for every atom in the universe there must have been a genesis in a stellar envelope (near the core) and a subsequent ejection from the star. But there are many different models for mass ejection from stars, not all of which are supernovae.

"Furthermore, most of the mass of the Solar System (e.g., the Sun) is lighter elements -- not supernova material."

Most of the mass of the universe is unknown.

Oh, I agree. But I said Solar System, not universe. Most of the mass of the Solar System is lighter elements that need not form in stellar cores.

... Heavy elements are believed to only come from supernovae and not from any other source. ...

See above comment ... heavy elements start just past lithium in the periodic table ... I pointed out several non-supernovae events that can cast mass off stellar envelopes and much of that mass can be "heavy" in this sense. Also, did you know that the Sun is surrounded by water vapor? Oxygen is a heavy element, making H20 a (not very) heavy molecule.

Stars cast off a significant amount of mass throughout their lives (especially in the early WR stages) and much of this material can be "heavy" ... I'm not aware of estimates, however, that show what percentage is heavy.

Anyway, this is very interesting and I will read more on it to find out more about it.

I agree! The whole idea of recycling in the universe is very appealing to me. But my main focus (and where I spend most of my reading time) is on the Solar System -- especially planetary geology and meteoritics. Meteoriticists are doing a great deal of research on recycling and planetary evolution.

 Questions about the Solar System:

1) Does the Sun suck in more mass each day from space debris and dust than it looses from its fission/fusion processes?

2) Mercury is said to have an unchanging face because of no erosion etc... What effect does the solar wind have on the surface of Mercury? With little or no atmosphere is the solar wind "felt" at its surface?

3) Venus rotates backwards. Where is the object that slammed into Venus? Is it Mercury or our Moon  or something else? Did it impact and become part of Venus?

4) Earth appears to be just as geologically devasted as Venus. Did a comet collide with us and bring extra water (from ice) with it? Did this impact plant the seeds of life?

5) Olympus Mons is huge. What stress caused this enormous pimple on Mars? It it erupted violently would the debris be shot out of Mars' gravitational hold? Where did Mars' moons come from?

6) Was there ever a planet at the asteroid belt? Some computer sims say Jupiter would not allow a planet to form there. What if the planet formed before Jupiter? Then later broke up from Jupiters' influence. What percentage of asteroids are spheres? (Spheres formed from hotter molten bodies)

Also, I have read that only one asteroid has a retrograde orbit. Do you know anything about it?

We may have discussed some of these in other threads but I thought it would be okay to list a few of my favorites here.

Cheers,

BQ 

 

brooksquest:

 Questions about the Solar System:

1) Does the Sun suck in more mass each day from space debris and dust than it looses from its fission/fusion processes?

Almost certainly not. There are other mass-loss factors, too. For example, a single coronal mass ejection event (CME) can launch from the Sun in seconds more mass than the annual influx.

2) Mercury is said to have an unchanging face because of no erosion etc... What effect does the solar wind have on the surface of Mercury? With little or no atmosphere is the solar wind "felt" at its surface?

Mercury experiences "gardening" effects from the solar wind. In fact, the influx of the solar wind at Mercury's surface actually gives it a tenous hydrogen (highly charged protons) atmosphere.

3) Venus rotates backwards. Where is the object that slammed into Venus? Is it Mercury or our Moon  or something else? Did it impact and become part of Venus?

Any answer here to this would be conjecture, since we have no evidence. It is thought (the Big Splat hypothesis) that our Moon was created as the result of a similar impact between a Mars-sized body and the Earth, and that the Moon accreted from a ring of matter disrupted from both bodies, while much of the mass of the impactor (and a good deal of Earth as well) was vaporized in the impact and that some of it remained with the Earth or fell back to Earth from near-Earth orbit. The same thing could have happened to Venus, with the collision being more head-on than overtaking.

There is a problem with any of these scenarios:

• Mercury is the leftovers from a Venus/impactor collision: what caused the matter to brake and stay in orbit insted of falling into the Sun? What caused the matter to fall to the orbital position of Mercury and how did the matter that is now Venus escape that fate?
• The Moon is the leftovers from a Venus/impactor collision: what cosmic coincidence allows a collision like that to result in a secondary collision with Earth and thereby form the Moon -- and allow all three bodies to establish stable orbits?
• How to account for accretion of leftovers from a Venus/impactor collision absent a stable orbit near Venus?

4) Earth appears to be just as geologically devasted as Venus. Did a comet collide with us and bring extra water (from ice) with it? Did this impact plant the seeds of life?