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Comment by frederikvs | Hacker News Reader

I don't think the term "space debris" is only applied to man-made space debris. Yes, there are rocks and other stuff out there, and those are just as dangerous as the man-made debris. AFAIK both types fall under the term space debris.

Of course, the fact that there's more and more space debris is quite clearly linked to everything we launch.

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This is somewhat correct. "Space debris" does include both human and natural debris. Since most natural debris orbits the sun and most human debris orbits the earth, Nasa uses the term "orbital debris" to refer to human caused debris.[0]

The difference in location means that while more natural debris enters earth's atmosphere, that doesn't mean that chances of colliding with natural debris is commensurately high. Orbital debris spends much more time near earth before it burns up, so has much higher collision chances per object that burns up.

In fact, the chance of collision with natural debris vs orbital debris will be very dependent on the specific orbit you are discussing as orbital debris is not evenly distributed.[1]

I higly doubt that there isn't a significant range of orbits where the risk of damage from orbital debris exceeds the risk from natural debris.

Edit: added citations

[0] https://www.nasa.gov/mission_pages/station/news/orbital_debr...

[1] https://www.nasa.gov/news/debris_faq.html

Really? I havent seen that math. For that to be true, the number of collisions would have to be rising faster than the rate at which we put stuff up there. Natural sources would cause a steady increase (more stuff launched, more exposed to natural impacts) whereas not-natural junk impacts should increase at a rate higher than exposure (compound increased exposure with increased risk from more objects). All i have seen are studies saying that the number of impacts is increasing, not that they are accellerating faster than launch rates.

No math is involved, only common sense : there's a certain amount of natural space debris surrounding planet earth. This amount has reached a steady state over the past few millions or billions of years. Over the past few decades we've started launching stuff into orbit. Some of that stuff explodes. Hence, there is now more debris surrounding planet earth.

Whether or not the amount of extra space debris has already caused an increase in collisions is a different matter, for which some statistics would be required. But that wasn't the point I was making.

In fact, it's quite the opposite of the point I was making : something has hit the ISS, and whether it's man-made or natural is (AFAIK) not specified at this time.

Something hits the ISS almost every day. This collision gets noticed because the hole it left is larger than average, but if you look close enough the ISS is covered in tiny impact damages.

This paper (2019) lists over 1400 impact sites on the ISS, and that is only the ones that have been discovered. https://www.hou.usra.edu/meetings/orbitaldebris2019/orbital2...

> there's a certain amount of natural space debris surrounding planet earth. This amount has reached a steady state over the past few millions or billions of years.

For what it is worth, I would question this assumption. Why would the amount of natural space debris around earth be at a steady state? Meteor showers [1] are one example of how the amount of space debris is not at a steady state.

[1] Meteor Showers: https://en.wikipedia.org/wiki/Meteor_shower

See Kessler syndrome (https://en.wikipedia.org/wiki/Kessler_syndrome).

The technical term is "micrometeoroids and orbital debris" (MMOD). (https://www.nasa.gov/centers/wstf/site_tour/remote_hypervelo...)

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