How has scientific understanding about the composition of the universe changed over time? Select the two correct answers.(1 point)
Responses
The percentage of dark matter has shrunk in scientists' estimates since the 1980s.
The percentage of dark matter has shrunk in scientists' estimates since the 1980s.
The percentage of unknown material has grown in scientists' estimates since the 1970s.
The percentage of unknown material has grown in scientists' estimates since the 1970s.
The percentage of dark energy has shrunk in scientists' estimates since the 1980s.
The percentage of dark energy has shrunk in scientists' estimates since the 1980s.
The percentage of ordinary matter has grown in scientists' estimates since the 1970s.
The percentage of dark matter has shrunk in scientists' estimates since the 1980s.
The correct answers are:
1. The percentage of unknown material has grown in scientists' estimates since the 1970s.
2. The percentage of ordinary matter has grown in scientists' estimates since the 1970s.
The correct answers are:
1. The percentage of dark matter has shrunk in scientists' estimates since the 1980s.
4. The percentage of ordinary matter has grown in scientists' estimates since the 1970s.
Scientific understanding about the composition of the universe has changed over time due to advancements in technology and new observations. One significant change is in the estimates of dark matter. Dark matter refers to matter that does not interact with electromagnetic radiation and cannot be directly observed. Since the 1980s, scientists have refined their estimates and the percentage of dark matter has actually decreased in their estimates.
Another change relates to the estimation of ordinary matter, which refers to the familiar atoms and particles that make up planets, stars, and everything we can see. Since the 1970s, scientists have made progress in understanding the distribution and abundance of ordinary matter in the universe. As a result, the percentage of ordinary matter has grown in their estimates.
On the other hand, the percentage of unknown material, which refers to any material that has not been identified or understood, has not necessarily increased over time. It is not a scientifically accurate statement to claim that the percentage of unknown material has grown since the 1970s.
Similarly, the percentage of dark energy, which is believed to be the dominant component of the universe responsible for its accelerating expansion, has not necessarily decreased since the 1980s. The nature of dark energy is still not well understood, and the estimates of its percentage have not significantly changed. Therefore, it is not accurate to say that the percentage of dark energy has shrunk in scientists' estimates since the 1980s.