Chairboy t1_iue9qdt wrote on October 30, 2022 at 5:51 PM

Reply to comment by phiggy in Remembering That Time the Soviet Union Shot a Top-Secret Space Cannon While in Orbit. by BalticsFox

> Two questions: 1. How long would a fired projectile take to reach going level?

What do you mean 'going level'?

> 2. How accurate could the gun be with the 1970s tech vs. 21st century tech?

1970s targeting and markmanship was very, very good. Add in that it could fire repeatedly and you could put a swarm of projectiles on an intercept that could hit a non-maneuvering vehicle far out.

boi-long t1_iuevmkf wrote on October 30, 2022 at 8:14 PM

Assuming they mean ground level (sea level)?

Chairboy t1_iuewsdf wrote on October 30, 2022 at 8:22 PM

Ooh, I could see that, autocorrect error instead of unfamiliar term.

/u/phiggy if that's what you meant, then it depends. If it was fired in the direction of travel, it would have an increased apogee but would eventually slow down from atmospheric drag and re-enter but it could take years because it's dense.

If it was fired 'backwards' to the direction of travel, it would probably take a little under an hour to hit the ground assuming it didn't vaporize on re-entry (lead might not fare as well as another bullet materrial? I don't know what they fired). Going from memory, it was Nudelman 37mm that was adapted for use in space and a quick Google says that it had a muzzle velocity of just under 700 m/s. A re-entry burn for a vehicle in LEO is usually like less than half of that so that should be enough to put the perigee inside the atmosphere where it would slow until it was falling straight down at its terminal velocity.