How did scientists find out about the planet Mercury and can they be sure about what they found?

Answer 1

Some of the oldest reliable records we have of astronomical observations were made by ancient Greek, Chinese, Indian, Egyptian, Mayan, and many other cultures. These describe the movements of "star like" objects in an otherwise unmoving star field. With more precise measurements made by the likes of Tycho Brahe and others, we became more *sure* of the accuracy and reliability of our findings (scientists like things to be repeatable, and tend to be unsure of singular or unobservable events). Some of the earliest theories set forth to explain these observed phenomena would seem very far fetched to us in contemporary society (like demons, dragons, battles of good and evil in Heaven), just as some of the theories proposed at the time (like the Earth not being the center of the Universe, which resulted in being publicly humiliated or burned at the stake) we now accept as normal facts. Eventually, society began trusting some of the logical thinkers who were coming up with these unusual ideas, because they reliably predicted events (like where a "star like object" would be at a particular time of a particular night, or eclipses, etc.). Nowadays, we accept these theories as facts, and even started naming some of these objects planets, or meteors, or comets, or asteroids, etc. Also, with bigger and cooler measuring devices such as telescopes we can make more detailed observations and get see more details on some of the closer objects, like planets and comets. In our quest for understanding, we named some of these objects, like Mercury which was theorised to be very hot because it was the closest to the Sun.