I mention this in the latest JSR but I don't think I talked about it on twitter. During launch of the CZ-5B/Tianhe, about 6 minutes after Tianhe and the CZ-5B separated they both came close to the ISS - under 300 km, which given uncertainties in trajectory is a tad alarming pic.twitter.com/SSHKKsKeTr

— Jonathan McDowell (@planet4589) May 10, 2021