The article does have hyperlinks, though, pointing to, for example https://blog.seas.upenn.edu/how-to-design-a-sail-that-wont-tear-or-melt-on-an-interstellar-vo

The article does have hyperlinks, though, pointing to, for example https://blog.seas.upenn.edu/how-to-design-a-sail-that-wont-tear-or-melt-on-an-interstellar-voyage/ https://blog.seas.upenn.edu/how-to-design-a-sail-that-wont-t... or https://breakthroughinitiatives.org/initiative/3 https://breakthroughinitiatives.org/initiative/3. The latter has a nice (and long) list of challenges to be solved.