Answer: is constant
Explanation:
In order to analyze the velocity of the stars within a galaxy, the <u>galaxy rotation curves</u> (developed by the American astronomer Vera Rubin) are used. These graphs are elaborated as a scatter diagram in which the orbital velocity of the stars present in a galaxy is represented on the Y axis and the distance of these stars to the center of the galaxy on the X axis.
Thanks to this diagram, it has been possible to observe a characteristic behavior in the rotation speed of the stars (and gas) present in the galaxies, which differs from the rules of the orbital movement of the planetary systems postulated by Newton and Kepler.
This means that in these galaxy rotation curves it has been observed that the rotation speed of stars and gas is "constant", regardless of the distance to the center of the galaxy. This discrepancy and these results were then used to demonstrate the existence of dark matter in the universe.
In 1946, Jordan became an independent state officially known as the Hashemite Kingdom of Transjordan, but it was renamed in 1949 to the Hashemite Kingdom of Jordan after the country captured the West Bank (Palestine) during the 1948 Arab–Israeli War and annexed it until it was lost to Israel in 1967.
The Natives who were able to tame the Salt and Gila Rivers were known as the <u>Hohokam</u>.
<h3>Who were the Hohokam?</h3>
- They were a Native American civilization that lived in the North American Southwest.
- They constructed extensive irrigation works to use the waters of rivers.
The Hohokam were in dry areas and yet needed water to grow crops and survive. They therefore constructed some complex and extensive canals to channel water to their settlements and farms.
Find out more on the Hohokam at brainly.com/question/5798355.
Arabian Peninsula is the largest peninsula in the Southwest Asia. It is located northeast of Africa and is on the Arabian plate. Arabian Peninsula is the second largest peninsula in the world, right after Europe. It consists of the countries Yemen, Oman, Bahrain, Qatar, Saudi Arabia, Kuwait, and the United Arab Emirates.