They arrive at the thing at L1 and begin a close examination of it.  They get a surprise when they probe it with radar.  They circumnavigate it and find something even more surprising.  Blunt is afraid and wants to go home.  They learn about the progress of the Sunwardian mission.  After the circumnavigation they get a shock.

https://oliveronline.ca/2018/09/27/the-plainsrunner-chapter-45/
https://greencomet.org/2018/09/27/the-plainsrunner-chapter-45/

rjb