Der Exoplanet „Baby“, der einem zwei Wochen alten Säugling entspricht, ist der jüngste außerirdische Planeten, der jemals gesichtet wurde – und er umkreist einen seltsamen Stern

> The newly discovered exoplanet, known as IRAS 04125+2902 b or TIDYE-1b, is a lightweight gas giant with a diameter slightly smaller than Jupiter’s but around 0.4 times the mass of the solar system’s largest planet. It orbits a protostar — a baby star still growing to its final size — located in the Taurus molecular cloud around 520 light-years from Earth and completes one rotation around the protostar every 8.8 days.

> Based on the age of the protostar, which currently has a mass of around 70% that of our sun, TIDYE-1b can only be up to 3 million years old — around 1,500 times younger than Earth. If you were to compare the exoplanet’s current age to a human lifespan, it would be a 2-week-old baby, researchers wrote in a statement. …

> … “Planets typically form from a flat disk of dust and gas, which is why planets in our solar system are aligned in a ‘pancake-flat’ arrangement,” study co-author Andrew Mann, a planetary scientist at UNC Chapel Hill, said in the statement. “But here, the disk is tilted, misaligned with both the planet and its star — a surprising twist that challenges our current understanding of how planets form.” The disk is believed to be misaligned relative to the star by around 60 degrees, Mann added in another statement. …

> … One possible explanation is that the disk has been pulled out of place by a companion star, which orbits the protostar at a distance of around 635 astronomical units (635 times the distance between Earth and the sun). However, this may be unlikely given how far away the companion star is, researchers wrote.

I think there is a much more likely explanation, which is that there were 2 or more, more massive planets than IRAS 04125+2902 b in this solar system.

I think 2 massive planets were required. The first perturbed the orbit of IRAS 04125+2902 b by a relatively small amount, but enough to cause a near-miss between IRAS 04125+2902 b and the third planet. This latter near miss changed the orbital plane of IRAS 04125+2902 b and threw it out of the protoplanetary disk, and into alignment with Earth, so it could be noticed by our orbiting infrared telescopes.

What became of the other planets?

1. They might still be inside the protoplanetary disk, and thus invisible to our telescopes.
2. One or both might be outside the protoplanetary disk, but orbiting at such inclinations that they are not visible by the transit method. Note that if this is the case, their wobble might be measurable in the movements of the star.
3. One or both of them might have been thrown into the star.
4. One or both of them might have been ejected from that solar system.

In the last 2 cases, obviously, there would be no remaining indications that the planets exist, unless one or both can be imaged directly, moving away from the star. This might be possible, since the star is only ~3000 years old.