What are the chances a space probe will make it to another star without hitting a bit of space dust?

Question

tl;dr: What is the density of "space dust" or micrometeorites in interstellar space, and how likely is it that a tiny interstellar craft could avoid hitting any?

In a future time we will likely figure out how to accelerate a usable space probe to 0.1c and shoot it to Alpha Centuri, considering there is already serious work being done on this topic.

If such a craft hits a particle, even something smaller than a grain of sand, it will probably be game-over for it (0.5*0.67mg*(0.1c)^2 = 300,000,000 joules, which is about a ton of TNT).

Considering that there are a lot of micrometeorites, at least around earth, and navigation at 0.1c is fairly difficult, what would be the chance of a space probe making it through interstellar space?

How should we know the density of interstellar dust? It is not measurable using telescopes. There is too few data from spaceprobes. By the way, a ton of TNT is equivalent to 4.184 · 10^9 J or 4,184,000,000 joules. So your particle should be a lot heavier. — Uwe, Apr 01 '19 at 15:53
Isaac Arthur did a YouTube video on this. I forget which one (an early one). The chances depend on the size of the particle (it decreases with increase in size). But I think the chance of not hitting something is basically zero. You need frickin' lasers! — rghome, Apr 03 '19 at 14:34
somewhat related: If a spacecraft travels at 10% c will it be destroyed by interstellar dust and particles? and Debris in interstellar flight and How serious is the problem of interstellar dust for interstellar space travel? — uhoh, Oct 03 '23 at 12:44

score 1 · Answer 1 · edited Oct 01 '23 at 21:55

According to the Ohio State University's Astronomy department

Composition: carbon, metals, silicates, and ice Size of grains: 500 nanometers or less in diameter (1 nanometer = 1 billionth of a meter) Number density of grains: 1 per million cubic meters

Of course, dust that small isn't likely to cause a huge issue, but 100% any spacecraft will hit many 500 nm particles.

Grains of sand are around 50 μm, so about 100 times larger. I don't know the distribution of larger particles, but it seems quite likely that there will be a fairly large number of such particles.

From this paper, the larger particles seem to be quite a bit rarer, but it seems still pretty likely that one will have to manage such sizes of particles, because space is really big.

What are the chances a space probe will make it to another star without hitting a bit of space dust?

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