For example: a lot of people still doesn’t know that Pluto is no longer a planet, but it has been reclassified as a dwarf-planet since 2006, and it has five known moons, being them Charon, Nix, Hydra, Kerberos and Styx, which comes as a surprise to many, since, until recently, Pluto was known to us all as a solitary planet, isolated in the final boundaries of the Solar System. Today, this image of Pluto is completely demythologized, since ongoing studies about this fascinating and distant dwarf-planet is going stronger than ever, unfolding new knowledge, as well as impressing evidences, about its functionality almost every day.

Very recently, in July 2015, the NASA spacecraft New Horizons – part of the New Frontiers program of discoveries – passed by Pluto, and all of its moons, after an almost ten years journey throughout space, focusing its study on Pluto and Charon, more specifically, and revealing for the first time in great detail curious characteristics of the dwarf-planet, unbeknownst to us all, until recently, although what we know – or what we think we know – about Pluto is only a drop in the vast ocean of possibilities.
When it comes to dwarf-planets, astronomical investigations virtually never stop. Ceres, the closest to Earth, being located in the asteroid belt, between Mars and Jupiter, recently had the NASA Dawn Spacecraft passing by its orbit, collecting new images and evidences about the mysterious dwarf-planet.

The extrasolar planets field of study is not just interesting, but very intriguing, since you can really learn the different types of planets that exist in the vastness of the universe, having, all of them, different measures, colors, compositions, sizes and masses, besides a lot of other peculiarities, which makes this particular field of study of great interest to a large group of astronomers. But even science can make its faults, and the scientific community not always agrees in all astronomical considerations and discoveries. Far from that, divergent points of view are more common than we think they are. One case of such notice evolving exoplanets concerns Alpha Centauri Bb, discovered in October 2012. Categorized now as a purely speculative extrasolar planet, considered the closest to Earth, being distant “only” 4.37 light-years from us, the group of European scientists that takes the credit for its discovery received hard criticism from several groups of astronomers, skeptical and cynical for the lack of concrete evidence supporting the discovery, thus affirming that the discovery team misinterpreted their own calculations and information in their database, probably being mistaken by false positives, which is, at least at certain times, a common astronomical factor for wrong conclusions, since much of its results are achieved by mathematical method. Today, the existence of this exoplanet is very controversial, and at least three different groups are involved in efforts to prove or disprove, for once and for all, its existence. In June 2013, a group of scientists gathered together to establish deeply, through scientific methods, the probability of the true existence of Alpha Centauri Bb, and the conclusions they reached turned its existence as highly unlikely.

As any of us can imagine, astronomy has very specific sectors of study, for each one of its many fields, and one of this fields occupies itself in the study of all the natural satellites in the Solar System, from the Earth’s moon to the five known moons of the dwarf-planet Pluto. The most studied moons are, undoubtedly, the Jovian’s Galilean moons – Io, Calisto, Europa and Ganymede –, Saturn’s Titan and Enceladus, and Neptune’s Triton, although there are several other moons in the Solar System extremely studied as well. With very specific programs of study and exploration for each one of the major natural satellites, one that can certainly be pointed out here is Enceladus, the sixth largest moon of Saturn, which has nowadays a lot of proposed missions, one of them being nicknamed as Enceladus Life Finder, whose goal is to send a spacecraft, equipped with technology able to enter the subsurface ocean of the moon, and investigate its potential habitability, unfolding – who knows – a whole new set of possibilities, that, until now, are of a merely theoretical speculative nature, although the importance of this mission cannot be minimized, especially if undertakes promising results, since a lot of similar projects, designed in the same category, are all under development in the present moment, being LIFE (Life Investigation for Enceladus) one of them. All of these projects combined will certainly perform a great degree of meticulous detailed study about this mysterious Saturn moon .

Astronomy is important to show us how little we are, inhabiting just a small planet, that could well be seen as just a grain of sand, in the unforeseeable vastness of the universe. Astronomy is also important to show us how much we can expand our knowledge about the universe. And as much as we are able to grow, as much as we are able to learn, we’ll acknowledge our own ignorance about this fascinating subject. It is not for us to establish specific truths about the galaxies, the planets, the several shapes of constellations that we know, to tell or not to tell if we are alone – or not – in the universe. Our final goal has to be aligned to the fact that we must improve our knowledge about the universe, little by little, every day, and, who knows, maybe we’ll be able, someday, to understand ourselves, when the comprehension of the universe, or at least, the most significant parts of it, are deeply rooted in the essence of our very existence, understanding that the process of learning should be infinite, as it is the universe, on which we are just a small – but important – part of it.
Wagner