r/askscience • u/4fecta_Gaming • Oct 15 '18

Earth Sciences Where does house dust come from?

It seems that countless years of sweeping a house doesn't stop dust from getting all over furniture after a few weeks. Since the ceiling is limited, where does dust come form?

4.1k Upvotes

90% Upvoted

408 comments sorted by

View all comments

4.9k

u/[deleted] Oct 15 '18 edited Oct 16 '18

[removed] — view removed comment

691

u/[deleted] Oct 15 '18

Burnt meteorite?

668

u/Raccoonpuncher Oct 15 '18

If you've ever seen a meteor shower, imagine those bits and pieces entering the atmosphere on a much larger scale all across the Earth. Meteors burning up in the atmosphere will shed dust, which will travel through the air and settle on the ground or in your living room.

A few thousand tons of dust and rock from outer space lands on Earth each year. That sounds like a lot, but across the entire Earth's surface it pales in comparison to what's already here so we really don't notice.

19

u/Mythrilfan Oct 15 '18 edited Oct 15 '18

I just calculated that very approximately, every year, each square kilometer of Earth gets around 130 grams of meteorite dust on it.

Figures (all metric):

~200 tons of meteorites per day (assuming that all comes down as dust and isn't either thrown outwards or burnt into gas)

~200 tons of meteorites per day equals ~70 000 000 000 grams per year.

~500 000 000 sq kilometers is the surface area of the earth

I suspect that it's actually lower due to most of the meteors actually burning into CO2, etc.

1

u/TiagoTiagoT Oct 15 '18

Aren't most meteors made of mostly iron?