Newb questions: sensors and lifepods

[Zook (OP)]

I had a single ship in a system, equipped with only a grav sensor, nothing else.  But it detected thermal signatures of alien ships at the exact same spot or close to it, and listed their active sensor types.  Does anyone know about those "minimal sensors"?

OK, after a while the aliens lost their patience with my survey ship and blasted it to smithereens.  The crew in the lifepods will have to be patient, because I don't have any ships with cargo capacity yet.  Or can any ship pick them up, as "surplus crew"? Is it worth the risk?

How do I salvage wrecks?

[Theokrat]

I had a single ship in a system, equipped with only a grav sensor, nothing else.  But it detected thermal signatures of alien ships at the exact same spot or close to it, and listed their active sensor types.  Does anyone know about those "minimal sensors"?

No idea on this one unfortunately.

OK, after a while the aliens lost their patience with my survey ship and blasted it to smithereens.  The crew in the lifepods will have to be patient, because I don't have any ships with cargo capacity yet.  Or can any ship pick them up, as "surplus crew"? Is it worth the risk?

Any ship can pick up the crew. They can then be disembarked on any planet, so they remain in your crew pool. It will not count as crew on the vessel picking up the survivor (at least as of 5.6)

How do I salvage wrecks?

With a "salvage" ship, i.e. a ship equipped with a salvage module. Importanly you should always have a cargo module along on the same ship or the task group so you can actually pick iup the salvaged minerals and modules. More cargo space is better.

[Beersatron]

I am fairly certain that every hull comes with ingrained 0.1HS EM and TH sensors - think of it as part of the particle shielding and detection system.

[Steve Walmsley]

I am fairly certain that every hull comes with ingrained 0.1HS EM and TH sensors - think of it as part of the particle shielding and detection system.

Every ship has a strength-1 EM sensor and a strength-1 Thermal Sensor

Steve