History of the Cosmos

Timeline of Astronomy

From ancient sky watching to James Webb — the greatest discoveries that shaped our understanding of the universe.

~30,000 BCE

Ancient Sky Watching

Cave paintings and bone tallies tracking lunar cycles.

~1500 BCE

Vedic Astronomy

Nakshatra system of 27 lunar mansions.

~600 BCE

Babylonian Star Catalogs

Systematic records of planetary positions.

~300 BCE

Greek Geometric Astronomy

Eratosthenes

Measurement of Earth's circumference.

476 CE

Aryabhata's Aryabhatiya

Aryabhata

Earth's rotation and accurate planetary periods.

~150 CE

Ptolemaic System

Ptolemy

Geocentric model with epicycles.

1543

Copernican Revolution

Nicolaus Copernicus

Heliocentric model published.

1609

Galileo's Telescope

Galileo Galilei

Moons of Jupiter, phases of Venus.

1609

Kepler's Laws

Johannes Kepler

Planets move in ellipses.

1687

Newton's Principia

Isaac Newton

Universal law of gravitation.

1915

General Relativity

Albert Einstein

Gravity as spacetime curvature.

1924

Andromeda as External Galaxy

Edwin Hubble

M31 is outside the Milky Way.

1929

Hubble's Law

Edwin Hubble

Universe is expanding.

1930

Chandrasekhar Limit

Subrahmanyan Chandrasekhar

Maximum white dwarf mass.

1967

Pulsar Discovery

Jocelyn Bell Burnell

First pulsar detected.

1969

Apollo 11 Moon Landing

First humans on the Moon.

1977

Voyager Launch

Grand tour of outer planets begins.

1990

Hubble Space Telescope

Orbiting optical observatory.

2008

Chandrayaan-1

Water molecules on the Moon.

2015

First Gravitational Waves

GW150914 binary black hole merger.

2021

James Webb Launch

Infrared flagship observatory.

2020s

Exoplanet Revolution

5,000+ confirmed exoplanets.

2030s

Artemis & Mars Sample Return

Planned lunar return and Mars samples.