A student made the following observations about astronomical bodies.

Question

Observation 1: The objects in the sky rotate once in 24 hours.
Observation 2: Jupiter's moons revolve around Jupiter.

Which observation(s) can be explained using the geocentric model?

Only observation 1
Only observation 2
Both observation 1 and observation 2
Neither observation 1 nor observation 2

Answer 1

The geocentric model, which places the Earth at the center of the universe with celestial bodies rotating around it, can be used to explain certain observations.

1. Observation 1: "The objects in the sky rotate once in 24 hours." This can be explained by the geocentric model, where the stars and planets appear to rotate around the Earth once every 24 hours.

2. Observation 2: "Jupiter's moons revolve around Jupiter." This observation is not easily explained by the geocentric model, as it implies a heliocentric understanding where moons orbit their planet (Jupiter) and planets orbit the Sun.

Based on this analysis, only observation 1 can be explained using the geocentric model.

So the answer is: Only observation 1.