How Are Planets Formed? New Information Reveals Unlikely 'Seeds' For Growing Planets

How are planets formed? It is one of the mysteries of the universe that many scientists are trying to answer. For a long time now, scientists assumed that planets are formed from small spherical dust particles. But new information reveals the seeds of a growing planet is actually smaller and fluffier.

In order to unlock the mystery on how planets are formed, Akimasa Kataoka from Heidelberg University and the National Astronomical Observatory of Japan, studied the dust evolution with polarimetry of young stars. Using the Atacama Large Millimeter/submillimeter Array (ALMA), Kataoka and his team observed a young star HD 142527.

HD 142527 is a 5-million-year-old star. It has twice the mass of the Sun and is 500 lightyears away from Earth. It has a ring of dust and gas that scientists believe are the fundamental building blocks of planets.

Using ALMA's high sensitivity to polarized radio waves, the team observed that the young star HD 142527 has a unique polarization pattern on its dust ring. Most of the dust ring has a polarization in a radial direction. However, the edges of the dust ring have a polarization in a perpendicular direction to the rest of the dust ring.

It is important to study the polarization of the dust ring. According to Kataoka and his team, they have hypothesized that the radio waves emitted by a young star HD 142527 and scattered by its dust ring carry a unique polarization pattern. Meaning the polarization pattern of a planet is unique just like a human's fingerprint.

By using the intensity of polarized emission, the scientists were able to measure the size of the dust particles. The dust particles measured around 150 millimeters. This measurement is 10 times smaller than the predicted size of dust particles in HD 142527.

Furthermore, the scientists believe that the dust particles are not spherical in shape but actually fluffy, complex-shaped dust particles, Sokendai reported. This new information contradicts the previous assumptions of scientists regarding the formation of planets.

The new information about fluffy dust particles as seeds of a growing planet is believed to alter the current planetary models used. It would also mean that the observed data collected should be analyzed and studied again based on this new information. In the study published in The Astrophysical Journal, Akimasa Kataoka added, "I believe the future progress will be full of excitement."