What is the main challenge astronomers face when trying to directly detect black holes? (1 point) Black holes are too black
Black holes are empty.
Black holes trap all light.
Black holes are too small.

Black holes trap all light.

Explanation:

This temperature is on the order of billionths of a kelvin for black holes of stellar mass, making it essentially impossible to observe directly. Objects whose gravitational fields are too strong for light to escape were first considered in the 18th century by John Michell and Pierre-Simon Laplace.

1. How do emission and reflection nebulae differ?

                        interactions with light

2. Where could scientists look to observe a black hole?

                              the center of the Milky Way

3. Which description best summarizes the steps that take place during black hole formation, in the correct order?

                         A massive star depletes its nuclear fuel; gravity overpowers               the star; supernova occurs; core of star collapses.

4. Select the correct answer from the list.

   To form a nebula, gravity pulls matter together or causes an explosion.

5. Which of these characteristics of a star make it most likely to become a black hole? Select the two correct answers

                                    It is dying.

      Its mass is greater than 20 times the mass of the sun.

6. Which statement best describes the galaxies closest to the Milky Way?

           These galaxies include irregular, spiral, and elliptical types.

7. Select the correct answer from the list.

Astronomers think that most galaxies are centered by a black hole  which exerts gravitational pull that binds the galaxy together.

8. What is the main challenge astronomers face when trying to directly detect black holes?

                                 Black holes trap all light.

Explanation: I got 100%

a tetrad is the foursome during meiosis made by two homologous chromosomes that have each already replicated into a pair of sister chromatids.

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explanation: