Is it safe to sleep outside without a tent when camping?

A.Yes, but you will likely need to take some other form of kit instead of a tent.

1. You will need something to lift you off the ground. This is normally some form of mat or in some cases if the surroundings allow a hammock. This will help keep you a bit warmer and drier as you will be off the damp cold ground.
2. You will need a good sleeping bag which has an appropriate temperature rating for what you are expecting to encounter. You may also consider a sleeping bag liner to add some extra warmth and comfort.
3. You should purchase a bivvy bag to sleep inside. This will help keep both you and your sleeping bag fairly dry should it rain. If you do not have one you will need to use tarpaulin to try and keep the rain off you.

The main problems with sleeping outside without a tent are:

1. It is harder to stay warm due to being in the elements more than if you were in a tent.
2. Harder to stay dry as you are not completely covered.
3. Risk of animals joining you in the middle of the night or insects landing on you.

If you are going to sleep in the open make sure you tie down any lose items to avoid animals being able to take them away in the middle of the night. In the morning shake all of your kit in particular your footwear to ensure no nasty surprises. You may even consider pulling socks over the opening of your footwear to stop anything entering them in the middle of the night.