What is the main challenge astronomers face when trying to directly detect black holes?(1 point)
Responses
Black holes trap all light.
Black holes trap all light.
Black holes are too small.
Black holes are too small.
Black holes are too black.
Black holes are too black.
Black holes are empty.
Black holes are empty.
Black holes trap all light.
A massive star depletes its nuclear fuel; gravity overpowers the star; supernova occurs; core of star collapses.
These galaxies include irregular, spiral, and elliptical types.
Emission nebulae and reflection nebulae differ in their interactions with light.
To form a nebula, gravity pulls matter together or causes an explosion.
Scientists could look to the center of the Milky Way to observe a black hole.
Which description best summarizes the steps that take place during black hole formation, in the correct order?(1 point)
Responses
Supernova explodes a massive star; remaining core expands; nuclear reactions diminish the effects of gravity.
Supernova explodes a massive star; remaining core expands; nuclear reactions diminish the effects of gravity.
A massive star depletes its nuclear fuel; gravity overpowers the star; supernova occurs; core of star collapses.
A massive star depletes its nuclear fuel; gravity overpowers the star; supernova occurs; core of star collapses.
Supernova triggers fusion reactions; massive star implodes due to extreme radiation; volume and mass of star increase rapidly.
Supernova triggers fusion reactions; massive star implodes due to extreme radiation; volume and mass of star increase rapidly.
A small star gains mass through fusion reactions; core of star collapses; increased radiation triggers a supernova.
Which statement best describes the galaxies closest to the Milky Way?(1 point)
Responses
These galaxies are all identified as spiral.
These galaxies are all identified as spiral.
These galaxies are independent of and unaffected by the Milky Way's gravitational pull.
These galaxies are independent of and unaffected by the Milky Way's gravitational pull.
These galaxies include irregular, spiral, and elliptical types.
These galaxies include irregular, spiral, and elliptical types.
These galaxies consist of mostly old stars.
How do emission and reflection nebulae differ?(1 point)
Responses
the presence of young stars
the presence of young stars
interactions with light
interactions with light
contain remnants of stars
contain remnants of stars
hard line edges
Question
Select the correct answer from the list.(1 point)
To form a nebula,
Select Answer
pulls matter together or causes
Select Answer
.