Astronomers discover a fourth planet in Kepler-51, challenging planetary formation theories with new questions.

The Kepler-51 system, known for having some of the least dense planets ever found, has a fourth member. We don’t know if the ...

Illustration of the Kepler-51 system and its inner three planets, which have unusually low density. New observations from NASA's James Webb Space Telescope suggest that at least one more planet is in ...

How many exoplanets are in the cosmos and what can they tell us about planetary formation and evolution? This is what a ...

14 September 2025 - 6 days for £2,169 per person. Discover the giant legacy of the Renaissance period astronomers Johannes Kepler and Tycho Brahe in Prague, the city of a hundred spires ...