How does the appearance of spiral galaxies vary? Select the two correct answers.(1 point)
Responses
Some are more elongated in shape than others.
Some are more elongated in shape than others.
They vary in how tightly their arms are wound.
They vary in how tightly their arms are wound.
They vary in the brightness of stars located on their arms.
They vary in the brightness of stars located on their arms.
Some have a band of stars and materials through their middle, but others do not.
Some are more elongated in shape than others.
They vary in how tightly their arms are wound.
The correct answers are:
1. They vary in how tightly their arms are wound.
2. Some have a band of stars and materials through their middle, but others do not.
The correct answers are:
1. Some are more elongated in shape than others.
2. They vary in how tightly their arms are wound.
To determine the appearance variations of spiral galaxies, scientists observe the following characteristics:
1. Shape: Some spiral galaxies can be more elongated in shape compared to others. This can be seen as a difference in the overall structure and symmetry of the galaxy.
2. Arm winding: The arms of spiral galaxies can vary in how tightly they are wound. Some galaxies have tightly wound arms that appear close together, while others have more loosely wound arms that appear more open and spread out.
3. Brightness of stars: Spiral galaxies also show variations in the brightness of stars located on their arms. Some arms may contain brighter, more luminous stars, while others may have dimmer stars.
4. Central bulge: Another variation in the appearance of spiral galaxies is the presence or absence of a central bulge. Some spiral galaxies have a prominent band of stars and materials running through their middle, known as a central bulge. Others may not have this feature, resulting in a different overall appearance.
By studying and analyzing these characteristics, astronomers can classify and identify different types of spiral galaxies, providing insights into their evolution and formation.