It all started with a cloud of gas and dust which, due to gravitational forces, gradually began to get denser and hotter and started to form a protostar at its centre - the initial stages of any star. When the temperature of the nebular core rose high enough to fuse hydrogen atoms into helium atoms, the Solar System's stellar engine ignited, radiating light and heat: the Sun was born. From the remnants of the molecular cloud emerged the vast empire of the Sun. A reign that extends for millions and millions of kilometres, ruled by the powerful gravitational pull of our Sun, where we can find a myriad of celestial bodies and wonderful worlds moving around their star like a perfectly synchronized machine.
150 million kilometres away from the Sun orbits an outstanding and cerulean planet, intimately connected to its star. That planet is Earth. And for our planetary home the Sun's influence plays a fundamental role on the maintenance of the physical cycles and, especially, the life cycles. Without the energy produced in the distant core of the Sun life as we know it would be impossible and our planet would exist as an utterly frozen and desolated place. The Sun warms the Earth, heats its surface, atmosphere, its oceans. The origin and destiny of life are closely connected to our star; many of the species that inhabit the Earth, both fauna and flora, need the Sun to survive. And Humans are no exception. We always had a deep bond with our star. Our ancestors worshipped it, and they were no fools in doing that. If there's something worth to worship, the Sun is undoubtedly a rational choice. Our yellow star has a profound impact in our lives since our first steps and we surely knew that its warmth and light were (and still are) vital for our existence and prosperity. It was a constant presence in our daily tasks and it was essential for agriculture; a poor harvest would certainly mean starvation.
Although most of us think of the Sun as a big yellow disc that always travels in the sky during the daytime, it still plays a very important role in our lives today. The star that sits in the centre of the Solar System can exert an astonishing influence on us and it is incredible how that massive sphere is able to affect our state of mind and emotional well-being, as well as our bodies, in such an imposing way. We are surely able to feel the enormous torrent of sheer energy that comes from the Sun and it's wonderful to think that, even with the abyssal distance that lies between the Earth and our star, its presence can still keep us warm and illuminated during the day. Just imagine how much energy output that star needed to produce to warm our bodies - and the entire Earth - at a distance of roughly 8 light-minutes.
However, the fate of our star is sealed: in about 5 billion years the Sun will die. It will become a red giant and its matter will eventually be ejected into the cold vacuum of space. The Earth's destiny is sealed as well because when the Sun becomes a red giant it is possible that our planet could be engulfed by the dying star and by then life as we know it will be long gone.
Until then, whenever you look up into the sky remember that our star is more than just that blinding disc. The Sun has a remarkable impact on the human existence as well as on the existence of all those others amazing lifeforms that inhabit the Earth. We are deeply connected to it and therefore we need to continually search for a better understanding of this wonderful star called Sun.
Imagery credit: NASA/SDO
Webgraphy:
http://solarsystem.nasa.gov/planets/profile.cfm?Object=Sun
http://www.nasa.gov/
http://www.nasa.gov/mission_pages/sunearth/index.html
http://science.nasa.gov/heliophysics/
http://www.esa.int/ESA
http://www.esa.int/Our_Activities/Space_Science/SOHO_overview2
