By Gabriel Ferrero “‘In this phial,’ she said, ‘is caught the light of Eärendil’s star, set amid the waters of my fountain. It will shine still brighter when night is about you. May it be a light to you in dark places, when all other lights go out.’ “1 These unforgettable words, that J.R.R. Tolkien…

By Gabriel Ferrero It is widely known that the sun, our closest star, is the main source of energy for our planet. We receive around 1017 watts from it, which is approximately the power that 10 thousand billion electric irons would consume. However, this is only a tiny fraction of the energy that the sun…

By Gabriel Ferrero The most accepted explanation about the beginning of the universe, usually known as the Big Bang theory, is founded on several observational facts. One of them is an astonishing discovery made by Edwin Hubble and Georges Lemaître in the late 1920s. They realized, both observationally and theoretically, that the farthest galaxies move…

By Gabriel Ferrero A galaxy is composed of a huge number of stars (usually around 100 000 million), gas (mainly hydrogen and helium) and dust, bound by its own gravitational force. There are many types of galaxies. According to their morphology, the main types are elliptical and spiral. In fact, we live within a spiral…

by Gabriel Ferrero During the current, long stage of its evolution, the Sun shines because, very deep in its core, millions of tons of protons (nuclei of hydrogen atoms) fuse every second to form nuclei of helium. For each four protons fused, one new helium nucleus is formed. However, the mass of a helium nucleus…

By Gabriel Ferrero Stars are bright because, deep inside their cores, nuclei of atoms of lighter chemical elements (mainly hydrogen, helium and carbon) fuse to form nuclei of heavier elements. Such fusion produces huge amounts of energy, high temperature and high pressure, that balance out the tremendous force of gravitational attraction. Then, for most of…