The man that mapped the sky

an essay on science history

Everyone remembers Newton for discovering that the laws of motion that govern heaven and earth were one and the same. Fewer remember Kepler for identifying the beautiful arcs that planets trace along their journeys around the sun. Fewer still remember Tycho who dedicated his life to recording the positions of planets and stars in the sky.¹

Tycho created the most accurate map of celestial objects of his time. He improved instruments and techniques of measurement, and spent night after night in his observatory, keeping records of the sky, while the rest of the world slept. He died before publishing his data, and it was Kepler² who compiled Tycho’s observations and published them as the Rudolphine Tables. Tycho would not live to see the scientific revolution that his work ignited.

The compilation of the Rudolphine Tables themselves required careful calculations, including corrections for the Earth’s spin about its axis and for the refraction of light in the atmosphere. Kepler, too, used Tycho’s data to draw out those arcs of motion that later inspired Newton. Kepler realized that the planetary orbits were in the shape of an ellipse.

Then, Newton imagined those arcs to be the arcs of a ball thrown so quickly that it would never fall to the ground. For once it reaches where it should touch the ground, the ground has fallen away. So beautiful is the motion of the planets under gravity that even now, over a decade after I first learned of the laws, I still find myself marveling at them.

Without the prior work of Kepler, Tycho, Copernicus, Ptolemy, and others whose names are now lost to history, Newton would not have had the data to develop the Laws of Motion.

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The pace of discoveries in physics has slowed considerably over the last two decades. Sabine Hossenfelder, physicist, argues in her book Lost in Math³ that this is due to a lack of data. Science needs empirical observations to test scientific theories against. If all current theories match all available empirical data then there is nothing for a theorist to do—the job is already done. Hossenfelder argues that the Standard Model of quantum physics already explains the available empirical data. To further test the limits of the model would require a collider so large it would need to be the size of a galaxy.

But not all of science has stagnated.

Over the last 20 years, The Allen Brain Institute has been painstakingly mapping the human and mouse brains. There have been developments in experimental techniques to measure different aspects of the brain⁴, and there have been improvements in the computational methods to handle the large amounts of data this project generates.

As astronomers mapped the sky, we now map the brain.

In other fields of biology—the United Kingdom, the United States, and other countries are creating large biobanks of human data, collecting health, lifestyle, and biological samples that will help us understand human health. The United States biobank, called “All of Us”, launched a little over five years ago, and will have over one million participants. The biobank efforts themselves are building off the work of the Human Genome Project, which completed the sequence of the human genome in 2001. The Human Genome Project was one of the most expensive scientific projects in human history, costing over $2 billion with the collaboration of labs across the world, and we are still working out what can be learned from this information.

There are still discoveries to be made. Let’s not forget those efforts—the systematic recording of observation—that so often go underappreciated.

1. Nor do people remember King Frederick II of Denmark who funded the construction of Tycho’s state-of-the-art observatory or the astronomers that came before Tycho and who Tycho learned from or those who assisted Tycho during his life.

2. who briefly worked with Tycho before his death

3. A book I highly recommend.

4. For example, we can visually see the activity of neurons using a technique called fluorescent calcium imaging.