well we know that the temp on the moon can peak @ 368 degrees and thats not counting a solar flare but im sure the shoes and rubber tires have a much higher melting point cause otherwise someone could have died up there!! [link to www.lunarpedia.org]
oh and there is this

When galactic cosmic rays collide with particles in the lunar surface, they trigger little nuclear reactions that release yet more radiation in the form of neutrons. The lunar surface itself is radioactive!

[link to science.nasa.gov]