Hacker News Reader

Comment by inglor_cz | Hacker News Reader

The lower orbits are fairly resistant to this because of the residual atmospheric drag. Any piece of debris whose orbit is under 500 km will burn up in the atmosphere within 5-10 years or so. That is known as orbital decay.

For something to stay up 1000 years, even a small object like a lost nut, it must orbit at least 900 km away from the Earth.

https://www.spaceacademy.net.au/watch/debris/orblife.htm

View on HN

And the moon is 384,400 km away. So, we've sent satellites and probes further than that.

True, but my reasoning was that we cannot really "lose space" for 1000 years by Kessler syndrome alone. The lower orbits self-clean much faster than that.

And Kessler syndrome, even if fully developed, will likely not prevent you from flying to other celestial bodies. Compared to an orbit, you only spend a very short time in the region cluttered by debris when leaving the Earth entirely.

Remember that volume increases exponentially with distance. Even large objects out that far are needles in a stack of haystacks.

Remember that volume absolutely does not increase exponentially with distance, it increases as the third power, which is polynomial. In fact, the word we use for "the third power" is even a direct reference to the fact that it's volume: cubic.

Agreed about the needle-in-haystacks part, though.

Oh, good, we'll only lose space for 5-10 years.

Most satellites orbit at 1000+ km.

Reply on news.ycombinator.com