Who is historically credited with discovering and proposing the heliocentric model of the solar system with the Sun at the centre?

Introduction / Context:
The structure of the solar system is a fundamental concept in astronomy. Historically, the heliocentric model, which places the Sun at the centre with planets orbiting around it, is associated with Nicolaus Copernicus. This question asks you to identify him from a short list that includes Galileo and other distractors. Understanding who introduced this model marks a key point in the scientific revolution.

Given Data / Assumptions:
• The question speaks of discovering and proposing the heliocentric model of the solar system.
• Options are Galileo, Finsen, Copernicus, and None of these.
• We assume the exam follows the standard historical convention that credits Copernicus with the classic heliocentric proposal, even though later scientists provided additional evidence.

Concept / Approach:
The correct approach is to distinguish between proposing a model and later providing observational support. Copernicus, in the sixteenth century, proposed that Earth and other planets orbit the Sun. Galileo, using a telescope, later gave strong observational support to this model. Finsen is unrelated to this topic. Therefore, when the question focuses on who first formulated the heliocentric arrangement as a system, Copernicus is the right answer.

Step-by-Step Solution:
Step 1: Focus on the phrase heliocentric model with the Sun at the centre.
Step 2: Recall that Nicolaus Copernicus published a work describing a solar system in which Earth moves around the Sun, breaking with earlier geocentric ideas.
Step 3: Remember that Galileo came later and used telescopic observations, such as phases of Venus and Jupiter's moons, to support the Copernican view.
Step 4: Recognise that Finsen is not connected with solar system models in standard history of science.
Step 5: Eliminate None of these because Copernicus does appear among the listed options and matches the description.

Verification / Alternative check:
To verify, think of how astronomy history is usually taught. The geocentric model is linked to Ptolemy, the heliocentric model to Copernicus, observational proof to Galileo and Kepler, and later gravitational theory to Newton. This clear story line makes Copernicus the name you should associate with proposing the heliocentric solar system. If you see his name as an option in such a question, it is almost always the correct one.

Why Other Options Are Wrong:
Galileo is wrong in this particular question because, although he supported the heliocentric model, he did not originally propose it. Finsen is unrelated to early astronomy in standard general knowledge references. None of these is wrong because the accurate name Copernicus is already present among the options. Therefore, only Copernicus correctly answers the question as framed.

Common Pitfalls:
Many learners confuse Galileo and Copernicus because both are key names in the shift from geocentric to heliocentric thinking. The easiest way to avoid this is to remember the timeline. Copernicus proposed the new model in book form, then later Galileo, Kepler, and others supplied strong observational and mathematical evidence. So for propose heliocentric model choose Copernicus, and for telescopic evidence or defence of the model think of Galileo.

Final Answer:
The heliocentric model of the solar system was proposed by Copernicus.