In recent research concerning our Solar System’s most massive planet, Jupiter, astronomer’s have managed to detect modes that will help them to measure the deep internal structure of the planet. Detection was done using the SYMPA Fourier spectro-imager which works similar to a seismograph here on Earth.
Seismology, the study of seismic waves, is most known for its use in the study of earthquakes. However, scientists have been using seismology to better understand both our Sun and fellow planets for over three decades, now.
Unlike the rocky structure of the Solar System’s four innermost planets, Jupiter is primarily composed of gas. It’s thick gaseous layers prevent scientists from seeing deep into the planet to deduce any information about the structure of the core. But, the advantage of Jupiter’s gaseous atmosphere is that it has a similar behavior to water when waves travel through it. For example, when a pebble is thrown into a pond the waves that are formed propagate out from where the stone fell. This action can also be seen in a large concentration of gas, such as that found on Jupiter.
An exaggerated version of traveling waves across a gaseous sphere.
When a wave starts at one end of Jupiter, it can travel across the entire planet finishing on the other side. The speed with which this wave travels gives scientists some idea of what the deep, unseen interior structure of Jupiter is like.
Depending on the size and composition of Jupiter’s core, the planet may have formed from gravitational collapse or from some form of accretion. These two types of formation are very different and suggest different ways that the planets in our Solar System formed.
Since the discovery of exoplanets, astronomer’s theory of how planetary systems form has been completely and utterly shaken. This is due to the fact that the majority of other planetary systems discovered look nothing like our own Solar System. There are planets 2 to 5 times more massive than Jupiter that orbit more closely to their host star than Mercury. When this was found, astronomer’s were forced to wrack their brains on how such a massive gaseous planet could form so close to its star because current planet formation theory did not support such an unexpected discovery.
Undoubtedly, planet formation theory has been revived as a subject of intense research. However, if we are to learn more about how exoplanets form we must first get a solid understanding of how our own planetary system was formed. Which is where using seismology to study the interior structure of our gaseous planets becomes so important.
If we can make a firm, unwavering conclusion about how the eight planets in our Solar System formed, then we will have a greater chance of solving the mysteries behind other bizarre planetary systems.