The largest planet in our solar system is Jupiter.

Explanation:

Jupiter is the largest planet in our solar system, and it is the fifth planet from the Sun. Here are some key points to understand why Jupiter is the largest planet:

Size and Mass:
- Jupiter has a diameter of about 143,000 kilometers (88,846 miles), which makes it more than 11 times the diameter of Earth.
- It has a mass of approximately 1.898 × 10^27 kilograms (1.898 × 10^24 metric tons), which is about 318 times the mass of Earth.
- Due to its large size and mass, Jupiter has a strong gravitational pull, which affects the motion of other planets and celestial bodies in our solar system.

Composition:
- Jupiter is primarily composed of hydrogen and helium, similar to the composition of the Sun.
- Its atmosphere is made up of layers of gas, including hydrogen, helium, methane, ammonia, and water vapor.
- Unlike Earth, Jupiter does not have a solid surface but rather a dense core made of rock, metals, and hydrogen compounds.

Great Red Spot:
- One of the most prominent features of Jupiter is its Great Red Spot, a giant storm that has been raging for centuries.
- The storm is so massive that it could fit several Earths inside it.
- The Great Red Spot is a result of Jupiter's fast rotation and the interaction of different atmospheric gases.

Moons:
- Jupiter has a total of 79 known moons, the four largest being Io, Europa, Ganymede, and Callisto.
- Ganymede, the largest moon in our solar system, is even bigger than the planet Mercury.
- These moons have diverse features, including volcanic activity, subsurface oceans, and icy surfaces.

Conclusion:
Jupiter's size, mass, composition, and unique features such as the Great Red Spot and its numerous moons make it the largest planet in our solar system. Its immense size and gravitational pull have a significant influence on the dynamics of our solar system, making it a fascinating object of study for scientists and astronomers.