I have the 1989 Melosh book, Impact Cratering, and it's an excellent book with one exception: it talks about the Tillotson EoS, and it details it a bit in an appendix, but it seems to leave something out. I was hoping someone here could help me to understand it.(adsbygoogle = window.adsbygoogle || []).push({});

The book gives the equation in my attachment.

It then defines everything except E, the energy density. So how do I find the energy density? The book gives the Hugoniot equation for energy density, but that is dependent on the pressure of an impact, and it's the pressure that I'm trying to find. (The book also gives a Hugoniot equation for pressure, but it says the Tillotson equation is better for extremely high pressure and hypervelocity impacts.)

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# Help understanding the Tillotson equation of state

Can you offer guidance or do you also need help?

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