Question

How do we know our galaxy is a flat disk?

Answer 1

HEYA MATE , HERE IS YOUR ANSWER

When you look toward the galactic center with your eye, you see a long, thin strip. This suggests a disk seen edge-on, rather than a ellipsoid or another shape. We can also detect the bulge at the center. Since we see spiral galaxies which are disks with central bulges, this is a bit of a tipoff

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