It's feasible that we'll meet other sentient life forms and conduct commerce with them. We don't now have the technology to physically travel outside our solar system for such an exchange to take place, but we are like Columbus centuries ago, learning fast how to get somewhere few think possible.

People quite often think of the question 'Are we alone in the universe?' in terms of other civilizations out there: life forms that have reached at least our level of technological development.

Super-Earths are how we call a family of planets... up to two times larger and about ten times more massive than the Earth.

Dimitar Sasselov Quotes