Get the default PSModulePath at runtime? #7082

Two questions on the PSModulePath in PowerShell Core:

1. Is the the default setting of PSModulePath in PS Core documented anywhere (e.g. online) in a way that is general and cross platform? Like a table of what it is on each supported platform, or a string with unexpanded platform-specific variables in it? (e.g. $PSHOME/Modules:$AnotherPlace/SecondModuleDir)
2. Is it possible to access the default PSModulePath at runtime? (Or to reset the current one?)