Starmap - Astronomy Apps for iPhone and iPad

The Earth has not always revolved around the Sun. For centuries, the Ptolemy Model was placing Earth at the center of everything. Why should it be otherwise? In the minds of little children, they are in the center of the universe, with their parents as generous gods. Imagine their distress, if in one instant, they would perceive the complexity and vastness of our civilization, and the very small part they play in it.

Mankind follows a similar path. As I began my studies, some thirty years ago, the possibility of extrasolar planets was only mentioned by my professors with an ironic grin from ear to ear. Today, hundreds of such planets have been observed beyond our Solar System. An article published in Nature in January 2012 now proposes the existence of billions of Earth-like planets in our galaxy. Thirty years ago, life in Universe was considered as a unique event. And now, what about extraterrestrial civilizations? I dream of living long enough to be present for this revelation.

As mankind grows up, we become smaller and smaller.

Throughout time, we have reassured ourselves with stories and models placing us at the center of the Universe, like Ptolemy’s model.

The story of Galileo and his tenacity to prove the Earth was revolving around the Sun is a key moment in the history of science. For centuries, the Church had accepted once and for all Ptolemy’s model, because it was placing the human being at the center of the creation.

Ptolemy’s approach, however, was not religious, but logical. His theory was explaining well enough the positions of planets and predicting the time of eclipses. The observation means of these times were simple geometrical landmarks for visual observations. Stonehenge must have had a similar purpose.

The real shock caused by Galileo was the confrontation between the tangible reality revealed by his telescope, contradicting the geocentric model of the Church. He had in plain view Jupiter and its satellites, understood as a reduced version of the Solar System. He could observe the phases of Venus and could only explain them by placing the planet around the Sun. Giordano Bruno, some years earlier had been burned for having upheld such ideas. But his approach was philosophical and not supported by observation. The future Pope Urban VIII had looked through Galileo’s telescope years before the trial he conducted against his friend.

Seeing and understanding, without believing, admitting that every model is wrong by essence … this is what we scientists learn on the benches of Universities. That’s sometimes a hard concept to grasp!

As the first images sent by the Hubble telescope came to our eyes, I remember some astronomers just denying them as they were not in accordance with the standard model of the time, which is now obsolete.

Today, the Earth is still flat.

Of course, we know it’s round in shape since we saw it with our own eyes as we stood on the Moon. What I mean by the Earth is flat, is that our perception of the shape of the Universe and of its evolution is as erroneous as pretending the Earth is flat. We know today that we cannot directly observe most of the matter composing our Universe, the dark matter. We know that our Universe is expanding, and that, counter to our physical laws, this expansion is accelerating. We have no idea of its shape or structure. Just plain hypothesis.

Since the large success of Starmap, I have been contacted by many users. Very modestly, among many others, my application has given them occasion to look at the stars and ask themselves some questions. Through the forthcoming articles, I will attempt to provide them with some keys, not for explaining our Universe, but to let them understand why we explain it the way we do.

Rephrasing a french saying … if you look for certainties, grow turnips, don’t look at the stars.

Some dates and milestones