The supermassive black hole at the center of our Milky Way Galaxy has a diameter of approximately 8 × 10-⁷ pc and is approximately 8000 pc away from us.Figure 13-13b of Discovering the Essential Universe,6th ed.,shows a drawing of the center of the galaxy with a size indicator showing 0.2 arcseconds.How does the angular size of the block hole compare to this?

Question

Quizplus · Accepted Answer

The diameter of the black hole is 8 × 10-⁷ pc and it is 8000 pc away from us. To find the angular size of the black hole, we can use the formula:

Angular size = (diameter / distance) × (180/π) × 3600 arcseconds

Plugging in the values, we get:

Angular size = (8 × 10-⁷ / 8000) × (180/π) × 3600 ≈ 2 × 10-⁵ arcseconds

This is too small to show up on the scale of the figure, which has an indicator of 0.2 arcseconds. Therefore, the answer is D, it is about 2 × 10-⁵ arcseconds-too small to show up on the scale of this figure.

The Supermassive Black Hole at the Center of Our Milky