As I see it there are two ways of conducting any sort of survey.
1). Long Distance - Long Term Observation. This is basically how we do it here on Earth. Build an observatory on the planet or in orbit for an instrument or instruments that absorb EMS radiation. Interrogate the data you collect for spectral information to find chemical composition and for physical data to find the physical characteristics of the star and any planets that may be present. Have your data peer reveiwed and publish.
2). Physical Exploration. If you know "Something" is "there" send an exploration vessel fitted with all the sensors you find in T5 plus a few geologist's hammers. Spend some time collecting data and samples, then return with the survey data and publish.
Both these methods can be accomplished in T5. 1). calls for the Scholar career 2). calls for the Scout Career.
There are no mechanics presented for checking systems from afar because Traveller empowers the referee to come up with Task rolls to represent players attempting to accomplish such a task as pointing a telescope at Tau Ceti to find out what kind of star it is and how many little green men live there. The referee decides the Task and generates the data for the Star and system and decides based on how well the player rolls how much information or how detailed their data is. Or maybe they fail the Task and the Referee tells them it was just too cloudy that night.
Can you jump into an empty hex? I say yes, based on the fact that you can choose to jump to a particular orbit you are essentially jumping to O=21+ i.e somewhere way outside the Oort Cloud of a system at approx 3 LY from the nearest star.
