Interactive Study Guide • Essential concepts, motions, seasons, and cosmic alignments visualised!
The motion of the Earth spinning on its own axis in space from West to East (anti-clockwise when viewed from the North Pole).
The movement of the Earth in a nearly circular path called an orbit around the Sun.
As Earth moves along its orbit, we look out in different directions into space at night. This changes the constellations visible in the sky month-by-month.
The Earth's axis of rotation is tilted (not straight up and down). As it orbits the Sun, different hemispheres get varying sunlight:
"Seasons happen because Earth is closer to the Sun in summer and further away in winter."
Earth's orbit is nearly circular! The distance difference is tiny. In fact, Earth is actually closest to the sun in January! Tilt is the 100% true driver.
The Moon passes directly between the Sun and Earth, casting its shadow onto Earth and temporarily blocking sunlight.
The Earth passes directly between the Sun and the Moon, blocking sunlight from reaching the Moon. The Moon enters Earth's shadow.
Ancient Indian master who proposed that the Earth rotates on its own axis, causing the stars to appear to move. He used the perfect analogy of a passenger in a moving boat seeing stationary trees on the bank move backwards.
A physical experiment demonstrating rotation. A giant 22m long pendulum is suspended in the Constitution Hall of the Parliament Building in New Delhi, continuously tracing out paths that show our planet's rotation below it!
Known as the father of modern Indian astronomy. He discovered a comet, established key observatories in India (including Kavalur), and dedicated his life to researching celestial movements.