# Could a mass made up of certain elements or compounds “disrupt” a star?

Inspired by this interesting question-- let's say that the universe was just really, really out to get a particular star, such as our sun. Is there a perfect cocktail where a mass significantly smaller than a star could cause the star to behave strangely after impact?

I'm not just referring to a massive pile of salts crashing into the sun and making a pretty multi-colored burst around the impact, but something that would disrupt the underlying nuclear processes of the star in a way that would be observable from Earth.

• "a mass significantly smaller than a star" ... I'll assume you mean the mass is significantly smaller than the star it's hitting, but perhaps clarify if you mean smaller by mass or by volume, and what order of magnitude you consider significantly for this purpose? – Kaithar Jan 18 at 15:52

One possibility is called a "Q-ball". A Q-ball is a finite-volume mass of bosons (net-zero-spin particles) theorized to exist by many flavors of string and quantum field theory. The bosons are not bonded to each other by traditional observations of the four fundamental forces, like gravity or electromagnetism, but instead due to a local attractive force within that mass which makes the Q-ball the most stable, lowest-energy arrangement of the particles within it. One additional theory is that this attractive force can cause the Q-ball to grow in size by capturing more bosons.

Now, the nucleus of a Helium-4 atom is a boson; the net spin of its 4 fermions is zero. Helium-4 nuclei could therefore be attracted to and captured by a Q-ball that wandered into the mass of a star. Bosons within the Q-ball would not undergo interactions like nuclear fusion, thus robbing the star of a key late-stage fuel and fusion source. This would affect the star's density and thus its temperature, disrupting the stable dynamic equilibrium of the star's interior environment, potentially slowing hydrogen fusion and creating a vicious cycle that, in theory, could eventually "kill" the star.

This was one theory proposed by the writer of the movie Sunshine, as a scientific basis for why the Sun's fusion was prematurely slowing (causing a reduction in solar radiation, and catastrophic global cooling of Earth, prompting two separate expeditions to deliver a vaguely-described device to "restart" the Sun). However, the Sun's mass is insufficient to trap a Q-ball, and our best estimates of the Sun's age indicate only 25% of its mass would be helium, with minimal helium fusion occurring, so even if a Q-ball were in the Sun, there's nothing significant it could inhibit for billions of years. And, should our Sun ever start to behave abnormally, there's nothing at all the human race could do with current or near-future technology to influence it; the entire mass of Earth is 1/333,000 the mass of the Sun, so anything we had available to use to build any such device would be a grain of sand on a beach relative to the raw energy of a star or anything that could possibly actually influence it.

• So, one Q-ball should be able to absorb all of star's helium while remaining stable and not collapsing? – Alexander Jan 17 at 18:01
• A q-ball that sucked up alpha particles would develop a pretty hefty positive charge in fairly short order, and coulomb repulsion would prevent further infalling. – Starfish Prime Jan 17 at 21:03
• I thought a Q-ball would be a fancy dress party with a guy who looks like John de Lancie, and some others... – EvilSnack Jan 18 at 3:05
• Gave me flashback of 63 Corvi mission finale from SpaceChem: steamuserimages-a.akamaihd.net/ugc/54374291174829697/… – val says Reinstate Monica Jan 18 at 5:40

Assuming neutronium is stable in sub-stellar masses (impossible to verify at this time), a chunk of that material, introduced with enough velocity to promptly penetrate to near the core of the star, then capture into an orbit (via gas drag), would have some significant effects on its hydrogen fusion process and the convection that delivers that energy to the outer layers where it can be radiated.

The mass involved might be as "small" as that of Jupiter -- less than 1% of the star's mass -- but the surface gravity of a neutronium sphere of that mass would be thousands of G, allowing it to create its own "atmosphere" even inside the star. Such an object is dense enough it could orbit inside the star (bypassing its core) for at least centuries, possibly as long as a million years. While doing so, it would be constantly accreting the stellar material (mostly hydrogen, of course) onto its surface, shrinking the star slowly even as it disrupts the star's circulation.

Then, at some point, the accreted material (which would include an ever-thickening layer of degenerate hydrogen) would initiate a runway fusion reaction, equivalent to (IIRC) a type Ia supernova event, potentially capable of completely disrupting both the neutron sphere and the host star.

• For added fun, send some anti-neutronium in on an intersecting orbit, Greg Bear style. – John O Jan 17 at 18:06
• "impossible to verify at this time" absent some handwavium, the substellar mass of neutronium would have insufficient self-gravitation to overcome degeneracy pressure and would go foom in short order, right? – Starfish Prime Jan 17 at 21:08
• @StarfishPrime That's the part we can't verify at present. We don't know, once the electrons and protons have fused into neutrons, whether there's any "pressure" from the tendency of neutrons to decay. Certainly degenerate matter on the surface would be lost at some lower limit, but neutronium isn't quite the same thing. – Zeiss Ikon Jan 19 at 3:05

# Strange matter

One single strangelet will do. It could weight as little as a light nucleus (such as that of an carbon or oxygen atom).

The thing about strangelets is that everything they interact with also becomes strangelets. This means the sun would be completely converted into strangelets in finite time.

For more information, see this video by Kurzgesagt, starting at 3:52 (or watch the whole thing to learn even more about this bizarre thing). The sun would still have the same mass, but it would become denser and dimmer.

Gamma ray burst: a typical GRB lasts less than a second - a 'long' one lasts several seconds. You can learn more about it here. They're caused by exploding stars, so given that two stars are travelling in exactly the same trajectory to one another - effectively in parallel in 3 dimensional space - a long lasting, focused GRB on your star could kill it - the star might supernova! The only thing that can cause one star to supernova is another - fight fire with fire!

Antimatter: Dropping enough anti-matter can probably take out the entire star through its annihilation process. I don't like this idea because if you're planning to annihilate the entire star, that would require a proportional amount of antimatter, and that's not very interesting, and where would you even get so much of it in one place? Might be too unlikely. But your choice. Here's a post with some numbers about it.

Black hole: nuff said

2 Other Stars: These other stars pass by your main star in a trajectory that is perpendicular to both your main star its co-star. The resulting forces would likely result in your main star being torn apart.

I'll add more ideas if I come up with any - I know that you asked for masses to slam into your target star, but I think this could also inspire some cool ideas. The other answers are also pretty good. I hope this helps!

• Dropping enough anti-matter can probably take out the entire star through its annihilation process. Do you mean fully annihilating the sun? Because that would take a sun's worth of antimatter. Of course if you just mean to blow it up it would require much less. – cowlinator Jan 18 at 3:15
• Yes that's what I meant - for a complete annihilation you need a sun's worth of anti-matter. I don't know the numbers for just blowing the sun up so I didn't provide any values. – cyber101 Jan 18 at 18:35

Drop anti-uranium into it. Assuming that:

1. Antimatter can occur naturally,
2. Matter-antimatter reactions actually do result in complete mass-to-energy conversion (to my knowledge nobody has ever proved this), and
3. The antimatter can get from point A (somewhere outside the solar system) to point B (the sun) without being completely annihilated,

then the result would be

1. A complete mass-to-energy conversion of the anti-uranium and the solar corona in its area. Provided that a sufficient amount reaches the sun, this would cause a massive solar flare. If you want to be really extreme, you could drop a mass the size of Jupiter into the sun, causing the sun to go supernova. A supernova would definitely be noticed, but this notice would only last about .00001 seconds.
• Seeing as the sun is about 99x more massive than Jupiter + everything else in the solar system combined, I don't think a jovian mass would be enough to trigger a nova. – Renan Jan 17 at 18:52
• @Renan if we are talking about antimatter, then there is complete 100% mass to energy conversion, instead of the 0.7% converted in a typical fusion reaction. So that would be a lot of energy suddenly delivered into the star. – Brianorca Jan 17 at 19:57
• @Renan Well, I was going to mention the massive amounts of energy delivered, but then Brianorca mentioned it. – SE is too politically correct Jan 17 at 20:18
• Why anti-uranium specifically? Does anti-uranium has some specific property which makes it more fitting for this purpose than other anti-elements? – Philipp Jan 18 at 17:35
• @Renan The OP did not designate that the sun come out intact, just that something happen which would be noticed by the inhabitants of nearby planets. A supernova counts, as it is guaranteed to be noticed, albeit only for a couple milliseconds. – SE is too politically correct Jan 19 at 1:11

I would swear that I saw a documentary saying that as soon as a start begins to produce iron, in that cascade of fusing heavier and heavier elements beginning with hydrogen to helium, it immediately goes nova. It also said that authors in Science Fiction have gone through so much trouble to explain killing a star with invented exotic devices, when all they really needed was a frying pan. Try googling that.

• I think you are describing a type 2 supernova. en.wikipedia.org/wiki/Type_II_supernova Perhaps some information from that link could be integrated into your answer, to fill it out a bit? It is quite short as is. Also, is seem implausible that a frying pan would kill a star. Lots of things fall into stars. Presumably some of the things are iron, but supernovas are quite rare. – Zwuwdz Jan 18 at 0:46
• The Sun already contains about a Jupiter mass of iron, leftover from its formation.. Adding an iron Earth isn't going to change much, as there's still a few billion years' worth of hydrogen in the core to hold the star up with fusion radiation pressure. – notovny Jan 18 at 1:36
• Adding heavy elements should shorten the Sun's life, though, yes? Even if a Jupiter's worth of iron only costs it a few seconds? – CAE Jones Jan 18 at 12:31
• @CAEJones Yes, but "a few seconds" is not noticable. – SE is too politically correct Jan 18 at 20:33