Thank you. I was confused when glancing over the paper. Incidentally, there are additional pictures attempting to convey the idea at https://www.dunlap.utoront

Thank you. I was confused when glancing over the paper. Incidentally, there are additional pictures attempting to convey the idea at https://www.dunlap.utoronto.ca/astronomer-discovers-tunnel-like-structure-may-surround-earth/ https://www.dunlap.utoronto.ca/astronomer-discovers-tunnel-l...