As countries develop weapon systems that can now reach into outer space, and countries have shown that they can target satellites with missiles, the very future of space exploration is in jeopardy. Space debris from destroyed satellites can potentially render entire orbits unusable for decades or even hundreds of years. Jonathan speaks with space debris expert Jiří Šilha about the uncertain future of space research in light of such weapons. – Repeat: Did you know that your life depends on tiny organelles called ‘mitochondria’? Jonathan speaks with Cambridge PhD researcher Petra Páleníková about these important but little-known organs at the cellular level and why scientists are keen to learn more about them.