Uploaded November 2021 | Updated September 2026, 2 hours ago

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Hey Tony here from Space but messier and today we’ll be starting a new chapter on the science of astronomy and how it came to be. Now this means we’ll cover everything from the ancient roots of science through the greeks, and psuedoscience all the way to astrology and what astronomy is now.

That will be a fun episode lol

So in this episode, we’ll learn about ancient science, where it all started, before we had modern scientific formulas and practices.

Scientific thinking comes naturally to us. By about a year of age, a baby notices that objects fall to the ground when she drops them. She lets go of a ball—it falls. She pushes a plate of food from her high chair—it falls, too. She continues to drop all kinds of objects, and they all plummet to Earth. Through her powers of observation, the baby learns about the physical world, finding that things fall when they are unsupported. Eventually, she becomes so certain of this fact that, to her parents’ delight, she no longer needs to test it continually. One day someone gives the baby a helium balloon. She releases it, and to her surprise it rises to the ceiling! Her understanding of nature must be revised. She now knows that the principle “all things fall” does not represent the whole truth, although it still serves her quite well in most situations. It will be years before she learns enough about the atmosphere, the force of gravity, and the concept of density to understand why the balloon rises when most other objects fall. For now, she is delighted to observe something new and unexpected. The baby’s experience with falling objects and balloons exemplifies scientific thinking. In essence, science is a way of learning about nature through careful observation and trial-and-error experiments.

Just as learning to communicate through language, art, or music is a gradual process for a child, the development of science has been a gradual process for humanity. Science in its modern form requires painstaking attention to detail, relentless testing of each piece of information to ensure its reliability, and a willingness to give up old beliefs that are not consistent with observed facts about the physical world. For professional scientists, these demands are the “hard work” part of the job but At heart, professional scientists are like the baby with the balloon, delighted by the unexpected and motivated by those rare moments when they—and all of us—learn something new about the universe.

Astronomy is regarded as the oldest science. Humans have been making careful observations of the sky for thousands of years. Part of the reason for this interest in astronomy probably comes from our inherent curiosity as humans, but ancient cultures also discovered that astronomy had practical benefits for timekeeping, keeping track of seasonal changes, and navigation. One amazing example comes from people of central Africa. Although we do not know exactly when they developed the skill, people in some regions learned to predict rainfall patterns through observations of the Moon.

The impact of ancient astronomical observations is still with us in our modern measures of time. For instance, The length of our day is the time it takes the Sun to make one full circuit of the sky. The length of a month comes from the Moon’s cycle of phases, and our year is based on the cycle of the seasons. The seven days of the week were named after the seven “planets” of ancient times which were the Sun, the Moon, and the five planets that are easily visible to the naked eye: Mercury, Venus, Mars, Jupiter, Saturn.

Note also that the ancient definition of planet (which meant “wandering star”) applied to any object that appeared to wander among the fixed stars. That is why the Sun and Moon were on the list while Earth was not, because we don’t see our own planet moving in the sky.

Even telling time down to the minute came from ancient observations of the sky, like how Some 4000 years ago, the Egyptians divided daytime and nighttime into 12 equal parts each, which is how we got our 12 hours each of a.m. and p.m. The abbreviations a.m. and p.m. stand for the Latin terms ante meridiem and post meridiem, respectively, which mean “before the middle of the day” and “after the middle of the day.”

Through time, we’ll see ancient civilizations create moments to mark the seasons like Stonehedge and Templo Mayor in the Aztec City of Tenochtitlan.

And this led to civilizations using the sun to inform a Solar calendar, which is our typical 12-month calendar we use today based on our revolution around the sun. Everyone that is, except for practicing Muslims, who use the lunar calendar, which is a 354-day year with 12 29-300 day months.