What are Gas Giants

If we travel back to the dawn of the Universe we see the abundance of Hydrogen and Helium that was created by the Big Bang to the order of roughly 98% of the total mass of the new Universe.  The remaining mass that comprised the other two percent of the rapidly expanding Universe was made up of Carbon, Silicon, Nitrogen, Oxygen, in relatively large amounts, and in percentage terms, just trace elements of everything else with which we are familiar from our periodic table.  Of course, these trace elements amounted to a mass of billions and billions of material substance greater than we can comprehend!

As expansion and contraction caused galaxies and solar systems to be formed, there was a period where planets, through gravitational effects, also started to form.  As rocky and metal interiors started to pull in more material, then more of the Hydrogen and Helium also became part of these new planets formation.  Certain planets created a structure of a more stable and solid form by attracting rocks, dust and ice, but if a planet had attracted enough gaseous material, it created a gas giant.  The first of the true Jovian planets.

A Jovian planet is thus a gas giant.  In our very own Solar System we have these Jovian giants.  The two largest planets in our system, Jupiter and Saturn, are Jovian planets.  Their formation by pulling in huge amounts of gaseous material identifies their sizeable gravitational influence.  The intense pressures at the very center of these giants compresses gases into a seemingly solid surface wrapped around its inner rocky core.  This surface layer of liquid metallic Hydrogen makes up a huge proportion of Jupiters mass and a very large proportion of Saturns.  This metallised Hydrogen also creates the extreme magnetic properties of each planet that delights and astounds astronomers and physicists.

A strange aspect of Jovian planets is their ability to emit more energy than they receive from solar radiation.  It can only be imagined what energy was given off by these beautiful planets during their creation, but as they age they are slowly reducing their output like the smouldering embers of a fire.

Jovian planets are truly some of the most spectacular of the wonders of our Solar System.  Their mix of their gaseous, metallic structure, coupled with their astounding magnetic influence and huge gravitational pull allows astronomers to observe some of the most beautiful formations of gaseous waves and magnetic fields.