We don't have synonyms for spheres yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are sphere and sphered.
(N) :
The Synchronized Position Hold Engage and Reorient Experimental Satellite are a series of miniaturized satellites developed by MIT's Space Systems Laboratory for NASA and US Military, to be used as a low-risk, extensible test bed for the development of metrology, formation flight, rendezvous, docking and autonomy algorithms that are critical for future space missions that use distributed spacecraft architecture, such as Terrestrial Planet Finder and Orbital Express.
(N) :
The Synchronized Position Hold Engage and Reorient Experimental Satellite are a series of miniaturized satellites developed by MIT's Space Systems Laboratory for NASA and US Military, to be used as a low-risk, extensible test bed for the development of metrology, formation flight, rendezvous, docking and autonomy algorithms that are critical for future space missions that use distributed spacecraft architecture, such as Terrestrial Planet Finder and Orbital Express.