It is a fact of life that 3D printed parts from an FDM (fused deposition modeling) printer have weaknesses where the layers join. Some of this is due to voids and imperfect layer bonding, ...

the twisted remains of a star that exploded as a supernova around 5000 to 10,000 years ago. During the star's final detonation, it flung its outer layers into space at more than 600,000 kilometres ...