I searched but couldn't find an answer. Right now, I am on my iPhone so I can't post my design. Having said that, I tried to build a sorium harvester. I selected the harvester hull, added civilian engines and a recently researched solium harvester and a ton of fuel tanks. I even added some cargo holds as I wasn't sure where it stored the sorium. When I give it a mission to go to Uranus (listed as a gas giant...keep your jokes to yourself) I only get the standard "picket", "extended orbit", etc. there is no "harvest choice"...
So, how do I get it to harvest? I tried just orbiting but nothing happened.