Sky At Night

[ivor4781]

in the last episode on meteors etc the presenter said more less factually that 40.000 tons of meteoric dust fell on the earth yearly. surely this is wild guess work seeing as the logistics of substantiating that would be astronomical

[Old_Geezer]

Doubt if it's wild. Surely they can search known areas and extrapolate from that, or alternatively they could extrapolate from meteors noted to get here ?

[EDDIE51]

40 Tonnes per Day = 14,600 Tonnes a Year is in the middle of the estimated range ,it is not known accurately. Some estimates are 300 Tonnes a Day = 109,500 Tonnes a Year
https://www.universetoday.com/94392/getting-a-handle-on-how-much-cosmic-dust-hits-earth/
If you read the link there is news of a study CODITA, that is intended to get a more accurate estimate. CODITA should start producing results soon.

[THECORBYLOON]

EDDIE, the OP didn't sat forty tonnes a day, it's 40,000 tonnes a year. Your link says the amount is within a range from 5-300 tonnes a day so they're not sure what the true figure is yet.

[vascop]

Whatever it is it's an EXTREMELY small percentage of the mass of the earth (approx. 6 x 10^24 kilograms)

[Zacs-Master]

'the logistics of substantiating that would be astronomical'

Haaaa!

[ToraToraTora]

extrapolation and estimation dear boy.

[ToraToraTora]

earth loses about 90000 tonnes a year off the atmosphere so any we can pick up helps offset that.

[ToraToraTora]

sorry I meant to say we lose off the atmosphere and radioactive decay.

[UzZiBiKeR]

You have 40 tons written in your answer. Try a comma after forty. The average amount of dust that falls on the earth daily is approximately 100 tons. Multiply that by 365 days in a year and you get the average of approximately 36,500 tons per year. You must realize first that meteors hit the earth daily, not just at night my friend. NASA knows the average after many years of taking data from meteors hitting daily. You just need to watch a portion of the sky for several months and then add up the number of meteors you see in the images divided by the number of days that you took those images. It is fairly simple. Take what you see at night and multiply by two to get the daily fall.