2024-11-25 Effects of nearby supernovæ on Small Bodies in the Solar system

It's like flogging myself. Exery day, more papers to review.

---

Nearby Supernova and Cloud Crossing Effects on the Orbits of Small Bodies in the Solar System

Supernovae can move stuff

The question asked above sort of answers itself. Of course Supernovae (and other "big bangs") can move anything they impinge upon. How much is maybe a more important question.

Since the ... early 1970s? isotopic data from lunar, then meteorite, samples have shown that the early solar system had been impregnated with nuclei like ²⁶Al, which had a short half-life (7.17*10^5 years), and so a considerable energy release (per unit mass) into the materials they impregnated. Since Al is easily incorporated into silicate minerals, it got all over the place. In the early Solar system, that was a significant source of energy, probably responsible for the (seemingly) easy melting of "small" asteroids, rapid heating of larger bodies. Then it stopped, and normal service (gravitational reorganisation ; colission ; accumulation og heat from the decay of longer-lived isotopes) was resumed. OK ; not "stopped", slowed down and rapidly became insignificant. But this ²⁶Al was a significant source of energy that was present in the early development of the Solar system, and isn't now.

The putative source of this material, and it's associated energy, is a supernova "near" to the early Solar system in it's early days. Consequences include that relatively small bodies (asteroids 4/ Vesta, 16/ Psyche ...) have obviously melted at masses considerably lower than modern Solar system compositions would suggest.

Until the detection of "daughter" isotopes of ²⁶Al in meteorite samples (which daughters were less abundant than in terrestrial camples), this was a pizzle. The discovery of the "daughter" isotopes moved the problem to that of how big, and when, did the supernova erupt, producing the ²⁶Al and injecting it into the pre-Solar nebula? It's very clear that it did, and the short lives of large (supernova-prone) stars makes it un-surprising. So it becomes a standard part of "planetogenesis". An early nearby supernova is accepted as a thing these decades. (If there is a dissenting opinion, I haven't heard it expressed.)

Then come the next questions : what would be the effect of such a supernova on the materials (and their arrangement) in the early Solar system? And also, what would be their effects in later stages of the Solar system? This paper concerns itself primarily with the effects of a strong interstellar wind on particles in the Solar system (which would be a necessity for implanting the above ²⁶Al, though this paper deals with later stages up to and including today.

Essentially, the strong wind applies a "kick" impulse to the orbits of particles. The effect of the kick is strongly related to the size of the particle being considered - a particle of 10cm or larger would be unaffected, while a particle of 1mm diameter would be given sufficient impulse to be destabilised in it's orbit, if not completely ejected from the system. Orbit destabilisation would likely result in the particle accreting onto a larger body, or again, being ejected by a close encounter. The geological record contains enough medium-lifetime nuclei (specifically ⁶⁰Fe

, half-life 2.6 × 10⁶ years) to estimate a nearby supernova rate of around 2 per 10 million years, meaning that the Solar system is frequently swept clear of it's dusty components. Including Saturn's finer rings - though their regneration from colissions between the larger bodies should regenerate the dusty component on a rapid enough timescale to explain the rings we see.

Ejection from the Oort cloud of a system ndergoing a supernova is, in passing, suggested as a potential origin for bodies like 1I/ `Oumuamua (not that that body is short of origin proposals, from the sensible to the fantastical).

Back to Article List.

End of Document
Back to List.