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Why is our galaxy a spiral?

Answer 1

No one really knows but it is the most common form of galaxy.

The only theory explaining "why" is the fundamental idea of objects in motion around a point: there is a super giant black hole at the center of our galaxy, and its gravity reaches at least to the edge of our galaxy. A plane extends from the black hole's equator outward in all directions, and all objects caught in its gravity have a tendency to move along this plane. This theory explains why the object appears to be flat spiral, but it is just a theory.

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Answer 2

Elena Antonova

The rotation of the disk and the existence of spiral arms—regions of enhanced density and star formation brought on by gravitational interactions between stars and interstellar matter—are the main reasons why our galaxy, the Milky Way, is a spiral galaxy.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.