Earlier today, NASA announced the discovery of a probable new dwarf planet 2012 VP113. Its perihelion is even futher than Sedna’s, at around 80 AU. Though not nearly as eccentric as Sedna (e = 0.698 compared to 0.859) and therefore with a much closer aphelion (around 450 AU), it’s still one of the few most eccentric relatively large bodies of the Solar System. Why is it so amazing? It might continue to tell us a story Sedna started: a story about the origins of our system and its early days. It shows that Sedna is not a unique anomaly and might point us towards further evidence for some of the theories what might have happened to perturb their orbits so much. Was it a close passing of another star from the Sun’s birth open cluster? Or possibly a massive rogue planet? And should we expect bodies even larger than Earth in the inner Oort cloud? Could it all together tell us more about the characteristics of the early accretion disc around the Sun and help us with the theory of planet formation, extended a bit lately by observation of other systems in various phases?
Quite a lot of objects similar to 2012 VP113 might be lurking beyond the Kuiper belt, waiting for their discovery; with periods lasting thousands of years, catching them all seems rather a long-time job. And a wonderful one too; a quest after the wild ancient history of our own home.
Amazing discoveries are being made every day and one cannot possibly learn them all, let alone try to comment on them. I usually don’t tend to comment since I usually would only be repeating what was said somewhere else at a greater length (or I’d offer my own perspective, wrap it up in further knowledge and publish it somewhere I’d get paid – such is the reality of a poor time-constrained writer) but I made a tiny exception today for several reasons. Sedna has likely lost its primacy as a dwarf planet with the furthest perihelion, and I’m quite fond of this object. It was the first one of its class, the one that kindled the imagination of scientists and suggested that a large-scale event like another star’s passing less than 1000 AU from the Sun might have occurred long time ago. I love the outer Solar System very much (not that I didn’t love the rest of it too, after all, I live in the inner part quite happily) so this finding excited me at the greatest level. I was extremely excited about gravitational waves lately, but this one just fell into an area much closer to me. Quite literally, too.
After all, both of these discoveries are fascinating narratives: one about the history of our universe, the other about our system. They’re mysteries; results of the work of brilliant dedicated detectives, developing still better methods and finding more and more clues. What more can a storyteller want?