Skin temperature of a surface exposed for age seconds, as a fraction of (T − T_air): 1/(1 + (age/312 s)^0.35), a fit to
pāhoehoe surfaces measured by Keszthelyi & Denlinger (1996): ~900 °C after 10 s, ~750 °C after a minute, ~600 °C
after five, from 1150 °C. A particle is far thicker than that skin, so its own temperature drives the flow while the
drawing glows at the skin's.
Skin temperature of a surface exposed for
ageseconds, as a fraction of (T − T_air): 1/(1 + (age/312 s)^0.35), a fit to pāhoehoe surfaces measured by Keszthelyi & Denlinger (1996): ~900 °C after 10 s, ~750 °C after a minute, ~600 °C after five, from 1150 °C. A particle is far thicker than that skin, so its own temperature drives the flow while the drawing glows at the skin's.