High-purity pivalic acid (PVA) dendrites were observed under convection-free conditions on STS-87 as part of the United States Microgravity Payload Mission (USMP4) flown on NASA's space shuttle Columbia in 1997. The telemetry video data show that PVA dendrites melt without relative motion with respect to the quiescent melt phase. With a small fixed superheat above the melting point, △T ≡ Tm -T{sub}∞, designated in the theory by a Stefan number, dendritic fragments melt and shrink steadily. Individual fragments follow a square-root time-dependence as predicted using a quasi-static conduction-limited approach [1].
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