Let's put aside the ethics/morals debate for a moment and consider the math.
To send a spacecraft, using our current technology, to the nearest star would take tens of thousands of years. There is no reasonable expectation that a spacecraft built using our current technology could survive that long, so we cannot simply do this yet. Realistically, we're at least centuries away from being able to do this. That gives us a lot of time to research these planets.
Enzymes are things invented by biologists that explain things which otherwise require harder thinking. -- Jerome Lettvin