Micrometeoroids and Orbital Debris 20 Mar 2007 Prepared

Micrometeoroids and Orbital Debris 20 Mar 2007 Prepared by Chris Tutt Project Manager 1 6/18/2021

MMOD Analysis • ISS MMOD design requirement given in SSP 52005. – – PNP = 0. 99999(A*Y) A = Hazardous surface area in square meters (52 m 2) Y = Exposure duration in years (5 years) For AMS-02, this gives a PNP requirement of 0. 997. • Analysis performed by KX using BUMPER II, which includes MMOD environment defined in SSP 30425. 2 6/18/2021

MMOD Risk Components • Four major risk areas – – Main Helium Tank Warm Helium Gas Supply TRD Gas Supply Tanks Mixing Tank • Main Helium Tank and Warm Helium Gas Supply assumed to have nominal endurance of three years. • TRD Gas Supply and Mixing Tanks assumed to have nominal endurance of five years. 3 6/18/2021

MMOD Shielding • Three shield designs currently envisioned – Multi-shock shield on starboard side of TRD Gas Supply – Stuffed Whipple Shield on port side of TRD Gas Supply – Aluminum Honeycomb Shield surround Warm Helium Supply 4 6/18/2021

Multi-Shock Shield 5 6/18/2021

Stuffed Whipple Shield 6 6/18/2021

Aluminum Honeycomb Shield 7 6/18/2021

AMS-02 MMOD Model 8 6/18/2021

AMS-02 Model on Station 9 6/18/2021

Main Helium Tank 10 6/18/2021

TRD Tanks Port View 11 6/18/2021

TRD Tanks Starboard View 12 6/18/2021

Warm Helium Tank View 13 6/18/2021

PNP Analysis Results Main Helium Tank Warm Helium Supply Xenon Tank PNP 0. 99753 0. 99991 1. 00000 % Total Risk 96. 2% 3. 5% 0. 2% CO 2 Tank Mixing Tank Overall 1. 00000 0. 9974 0. 1% 14 6/18/2021

HITF Testing • Main Helium Tank PNP values verified by test. • 7 mm sphere shot at 6. 92 km/sec dented but did not fracture helium tank. 15 6/18/2021

Warm Helium Tank Results 16 6/18/2021

Future Work • Design team continues to look at ways to optimize shielding. – Moving components to reduce exposure. – Optimizing shield design to save weight. – Review shielding/MLI requirements to see if items can be combined. • Any changes will be reassessed using BUMPER and will be shown to meet requirements. 17 6/18/2021