We couldn’t communicate with them by any currently known method. Unless physicists make some kind of wildly unanticipated new discovery, there is no practical way that humans could travel there, either.
Potentially we could use interstellar probes to drop coded messages all over the planet. Maybe the inhabitants could respond by setting huge geometric fires that we could observe from space. We would have a lot of time to think about whether making contact is a good idea and, if so, how best to do it. Each back-and-forth message would take about 9 years—and remember, this is for the very nearest star.
Right now, NASA has a detailed set ofrules to make sure that humans do not contaminate Mars or other possibly habitable worlds.
On Earth, meetings between technological and non-technological cultures have generally not gone very well. If we ever get to the point where we find a non-technological culture on another planet, I expect that we will have enough good sense to observe from afar and not interfere.
The GLP aggregated and excerpted this blog/article to reflect the diversity of news, opinion, and analysis. Read full, original: What if We Discovered an Alien Civilization Less Advanced Than Our Own?