"Countless [...] researchers, scientists, and engineers [...] poured their souls into construction."
The Tiayang Shen was a secret Chinese probe that was originally supposed to orbit Venus and Mercury.
It was the most technologically advanced probe they'd ever made. CNSA gave it to NASA to help save Mark Watney and bring him back to Earth in return for getting one of their astronauts on the next ARES mission. Some of the workers at CNSA weren't happy with this trade because it had cancelled their original plans and they believed this was an unfair trade and wouldn't get enough funding to rebuild the probe.
' 太阳神 ' (Tàiyáng shén) translates to 'The Sun God' according to Google translate.