Supernova SN-1987a when a star exploded in a dwarf galaxy (Large Magellanic Cloud) next to our milky way galaxy. This event has been fortunate for the last supernova happened about 300 years ago. In year 1987, physicist and astronomers has the technological capabilities to examine his explosion in tight scrutiny. Separate neutrino detectors on earth detected a burst of neutrino particles on that day which is consistent with the theory where 99% of supernova energy is radiated away in the form of neutrino.
When the star was younger the energy generated will push the gas apart from collapsing due to gravity. Now that the star has run out of fuel, essentially there is no more energy to hold on and gravitation takes place, the core of the star is literally crushed. During this process, within seconds, the collapse and the rapid rise of temperature due to it will trigger a tremendous explosion: a supernova. Temperature will reach unprecedented heights again and the process makes the star a billion fold brighter, visible throughout the galaxy. Now, with an explosion of such grandeur scale, elements heavier than iron can start to form, making all the elements in the periodic table possible, uranium included.
When all the guts of the star scattered into the stellar neighbourhood, it became a seed for a second generation of stars. Elements that are heavier than hydrogen: Oxygen, Carbon, Nitrogen, Helium became abundant. Sounds familiar? These are the ingredients of life, DNA, as we know it. Our sun when viewed with special instruments revealed itself to contain about 2 percent of heavier elements because our sun is a second or third generation star.
Our solar system is therefore built from the ingredients left from the ash of a previous brilliant gem in the cosmos. Heavier elements stick together due gravity to form planets with solid surface – and that is where our picture comes in.