This document provides a brief timeline of important events and discoveries in the history of physics and astronomy from ancient times to the 20th century. It mentions that humans first made tools from stone, wood and bones, and discovered fire. It then outlines key contributions from ancient Greek thinkers like Empedocles and Aristotle on early theories of matter. The timeline notes important early astronomers like Eratosthenes, Ptolemy, Copernicus, Tycho Brahe, Kepler and Galileo and their discoveries about the Earth, planets and telescopes. It discusses later discoveries and theories from Newton, Franklin, Volta, Maxwell, Hertz, Planck, Einstein and Heisenberg that revolutionized physics. Finally, it mentions Hubble's work on galaxies and

1. Rey – Mark G. Basagre
istory and hilosophy
of cience and
athematics
Masters of Arts in Physics Education Student

2. Humans make the
first tools from
stone, wood, antlers,
and bones.
Humans
Discover
fire.

3. Empedocles
said that
the world
is made of
four elements, earth, fire, water and
air.
Aristotle accepted
the theory of the
four elements.
However he also
believed that the Sun,
Moon and planets are made of a fifth element and
are unchanging.

4. Eratosthenes calculated
the circumference
of the Earth.
Ptolemy stated that the Earth is the center
of the universe.
The sun and
the other
planets orbit
the Earth

5. Nicolaus Copernicus
realized that the
Earth and
the other planets
orbit the Sun.
However his theory
was not published
until just before
his death.
Tycho Brahe in 16th century made accurate
observations
of the
positions
of stars.

6. Johannes Kepler - In the
16th century
people believed
that the planets
move in circles.
Kepler publish
two laws of
planetary motion
in 1609.
Galileotested the theory
by dropping two different weights from the
leaning
Tower of Pisa. Galileo telescope was able
to see several
things invisible
to the naked eye.
1650

7. Isaac Newton
He invented a reflecting
telescope. Newton
also published his masterpiece
Philosophiae
Naturalis Principia Mathematica
in 1687.
1752 Benjamin Franklin
proved that lighting is a form of electricity.
1800 Allessandro Volta
invented the first
chemical battery.

8. 1873 James Clerk Maxwell
showed that light is
an electromagnetic
wave.
1888 Heinrich Hertz proved
the electromagnetic
waves predicted by
Maxwell exist.
Physics was
revolutionized
by two men,
Max Planck and
Albert Einstein. Planck proposed quantum theory.
Einstein published his theory of Special Relativity in and
his General Theory of Relativity.
1900 - 1915

9. In 1927 Werner Heisenberg (1901-1976) published his uncertainty principle.
In the 1920 - Edwin Hubble showed that our galaxy is only one of many
galaxies. He also proved that the universe is expanding. The Hubble Space
Telescope was launched in 1990.
In late 20th - Stephen Hawking is known for his research into black holes,
relativity and cosmology.
20th Century