ETA CARINAE IS AN EXTREMELY MASSIVE BINARY SYSTEM WHOSE STRONG WINDS PRODUCE A VARIETY OF HIGH X-RAY ACTIVITIES. EARLIER INTEGRAL AND SUZAKU OBSERVATIONS OF THE STAR SUGGESTED NON-THERMAL EMISSION FROM HIGH ENERGY PARTICLES ABOVE 10 KEV WHICH MIGHT BE RELATED TO THE FERMI GEV GAMMA-RAY SOURCE. JOINT NUSTAR AND XMM-NEWTON OBSERVATIONS OF THE STAR NEAR PERIASTRON IN 2014 DID NOT THIS EMISSION BUT ANOTHER JOINT OBSERVATION IN 2015 JULY AT THE ORBITAL PHASE 0.17 DETECTED A CLEAR EXCESS COMPONENT ABOVE 17 KEV. THIS RESULT MAY SUGGEST SHOCK ACCELERATION OR EXTREME SHOCK HEATING BY THE WIND COLLIDING SHOCK WHICH IS IMPORTANT FOR COSMIC RAY ORIGIN OR STELLAR EVOLUTION THEORY. WE PROPOSE A DEEP NUSTAR OBSERVATION OF THE STAR NEAR APASTRON TO UNDERSTAND THE NATURE OF THIS COMPONENT.

University Of Maryland Baltimore County, Baltimore MD

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