An excavator moves the remnants of felled trees in front of precision-engineered tunnel segments at the South Portal site for the Chiltern tunnel section of the HS2 high-speed rail link on 9th July 2021 in West Hyde, United Kingdom. HS2 Ltd has announced the launch of the second 2,000-tonne tunnel boring machine TBM, named Cecilia after astronomer and astrophysicist Cecilia Payne-Gaposchkin, to excavate a second 10-mile tunnel beneath the Chilterns.