- Diameter: Approximately 100,000 light-years

- Mass: Approximately 1 trillion solar masses

- Contains an estimated 200-400 billion stars

- Has a barred spiral structure with multiple arms

- Home to our Solar System

- Located in the Local Group of galaxies

Andromeda Galaxy (M31)

- Diameter: Approximately 220,000 light-years

- Mass: Approximately 1.5 trillion solar masses

- Contains an estimated 1 trillion stars

- Has a giant elliptical structure without well-defined arms

- Nearest major galaxy to the Milky Way

- Also located in the Local Group of galaxies

Key Differences:

- Size: Andromeda galaxy is larger in size compared to Milky Way galaxy, with a greater diameter and mass.

- Shape: Milky Way is a barred spiral galaxy with multiple arms, while Andromeda is a giant elliptical galaxy without well-defined arms.

- Number of Stars: Andromeda has an estimated 1 trillion stars, which is more than the estimated 200-400 billion stars in the Milky Way.

- Distance: Andromeda is located about 2.5 million light-years away from Earth, while the Milky Way is our home galaxy and is considered the center of the observable universe.

- Both galaxies are expected to eventually merge into a single larger galaxy in about 4 billion years.