What is the central idea of the passage?
O A.
astronomers and their discovery of the Orion Nebula, a bright nebulae
OB.
that the Orion Nebula is located below Orion's Belt 1,500 light years away
la situated below
ebulae and is visible
ocated at a distance
ebula is the closest
stimated to be 30
O C.
how far the Orion Nebula is to Earth and its impact on star formation
OD.
the Orion Nebula and how it is one of the most studied celestial features