What if the mysterious "Planet Nine" isn't a planet at all?

In this episode, we journey to the distant frontier of our Solar System to explore one of astronomy's strangest modern hypotheses: the possibility that the unseen object influencing the orbits of distant icy worlds could actually be a primordial black hole, an ancient relic formed in the first moments after the Big Bang.

Along the way, we'll revisit the discovery of Neptune, learn how astronomers detect objects they can't even see, and discover why gravity often reveals secrets long before telescopes do. We'll also look at the real observatories and sky surveys that may one day solve the mystery once and for all.

Then we'll head outside for your complete night sky guide for July 5-18, 2026, featuring the upcoming New Moon, Saturn in the morning sky, a beautiful crescent ...