What would the temperature rating of a space blanket/reflective tarp be?
Sleeping bags have temperature ratings that tell you the aproximate temperature that will be comfortable at.
Reflective tarps do not have such ratings, probably because most people don't use them for sleeping, except in emergencies. However, they are much lighter than a sleeping bag and are warmer than not having one.
What would the temperature rating of a reflective tarp be, if it had one?