There are a bunch of life support techs just after logistics. Researching them will provide a civ wide bonus to range (which will allow your ships to travel further) and will unlock new life support modules (when installed, they'll allow the ships to travel even further). Logistics 4 has a super project that when built will provide a civ wide bonus to range.

It should be noted that range is the distance that a ship can travel from a planet or starbase. In other words, if you felt up to it, you could build a path of starbases so your ships could travel where they need to go.

You are not likely to encounter this unless you seriously try to max out your range limit. There is something of a range barrier (a bug maybe?) where additional life support modules will not increase your range beyond it. Once encountered, you will need need new planets and starbases to go further.