Lucky Starr and the Big Sun of Mercury

<b>From the front flap of the Gregg Press edition:</b> "When Lucky Starr and his cocky little pal Bigman arrive on Mercury, they are under orders from the Council of Science to put a stop to sabotage that is threatening Project Light. But they step into a tangle of mysteries that appears to have no possible solution. Is the sabotage being done by Sirians - humans from the warlike planet of Sirius, who are known to want Earth's resources? Or by Dr. Scott Mindes, head of Project Light, for his own twisted reasons? And what part does Jonathan Urteil, roving investigator for an unscrupulous senator, play in the intrigue on Mercury? Lucky and Bigman must face a variety of deadly enemies - a mad robot, tentacles of living rock - before they find the shocking answers to their questions."