Astronomers Have Solved A Long-Standing Mystery About The Planets

• 18.08.2026, 16:41

A unique system of three stars led to the solution.

Astronomers have discovered that the orientation of the protoplanetary disk around a triple star system in the constellation Orion was altered by a stream of interstellar gas approximately 1.9 trillion kilometers long. The discovery may explain why astronomers find planets with orbits that do not align with the rotation of their stars or the plane of the ecliptic. The study’s findings were published in *The Astronomical Journal*, according to Space.

The triple star system GW Orionis is located approximately 1,300 light-years away from us. In other words, it is a system consisting of three young stars that are still forming. A protoplanetary disk of gas and dust has been discovered orbiting these stars, within which planets are forming. This is a unique event in itself, as such a disk around three stars is rarely detected. But what surprised astronomers even more was that the three rings making up the protoplanetary disk have different orbits around the triple star system.

Each ring is tilted at a different angle relative to the ecliptic plane. The outer ring is tilted the most. The disk consists of three rings located at distances of 6.7, 28, and 51 billion kilometers—or 44, 187, and 340 astronomical units—from the center of the triple star system. For comparison, Earth is located 150 million kilometers, or 1 astronomical unit, from the Sun.

It was previously believed that an invisible giant planet had caused the disk to deform and altered its orientation. Now, however, scientists have discovered that this is caused by a massive stream of interstellar gas about 1.9 trillion kilometers long—or 0.2 light-years. The exchange of angular momentum—or rotational energy—between the gas stream and the rings leads to the deformation of the disk.

It is believed that such gas streams, consisting mainly of hydrogen, contribute to the growth of stars by transferring mass to them. This flow originates from the remnants of a molecular gas cloud from which the triple star GW Orionis formed.

This discovery may help solve a long-standing astronomical mystery. In the Solar System, all the planets orbit the Sun in the plane of the ecliptic, which is aligned with the Sun’s equator and the direction of its rotation. Most planets in other star systems orbit their stars in a similar manner. But astronomers have previously discovered that some planets have highly inclined orbits and rotate in the opposite direction to the way their stars rotate on their axes. It appears that some cosmic force has altered the orbits of these planets. Perhaps this force consists of gas flows similar to the one discovered by the astronomers.