Populations I and II, in astronomy, two broad classes of stars and stellar assemblages defined in the early 1950s by the German-born astronomer Walter Baade. The members of these stellar populations differ from each other in various ways, most notably in age, chemical composition, and location within galactic systems.
What is the difference between population I and Population II stars?
Population II stars formed when the abundance of elements heavier than hydrogen and helium was low. Population I stars formed later, after mass lost by dying members of the first generations of stars had seeded the interstellar medium with elements heavier than hydrogen and helium.
What is population 2 in the Milky Way galaxy?
The stars in globular clusters, found almost entirely in the Galaxy’s halo, are also classified as population II. Today, we know much more about stellar evolution than astronomers did in the 1940s, and we can determine the ages of stars. Population I includes stars with a wide range of ages.
How do stellar populations differ from each other?
The members of these stellar populations differ from each other in various ways, most notably in age, chemical composition, and location within galactic systems. Since the 1970s, astronomers have recognized that some stars do not fall easily into either category; these stars have been subclassified as “extreme” Population I or II objects.
How old is population II?
Population II consists of the oldest observed stars and clusters, which formed about 1,000,000,000 to 15,000,000,000 years ago.
What is the difference between population I and population II stars in terms of chemical composition?
Population II stars formed when the abundance of elements heavier than hydrogen and helium was low. Population I stars formed later, after mass lost by dying members of the first generations of stars had seeded the interstellar medium with elements heavier than hydrogen and helium.
What is the difference between population I stars and population II stars describe each and identify their differences quizlet?
Population I stars are usually the blue younger stars. They orbit in the disk and they are relatively rich in metals. Population II stars are the red, older stars that lies in the bulge and halo of the Galaxy. They orbits in the elliptical orbits in the halo.
How are population 1 stars different than population 2 stars quizlet?
Population I stars include the sun and tend to be luminous, hot and young, concentrated in the disks of spiral galaxies. They are particularly found in the spiral arms. Population II stars tend to be found in globular clusters and the nucleus of a galaxy.
What are population 1 stars in the galaxy?
Population I stars Population I, or metal-rich, stars are young stars with the highest metallicity out of all three populations and are more commonly found in the spiral arms of the Milky Way galaxy.
What are population II stars quizlet?
population II stars. stars poor in atoms heavier than helium ; relatively old stars nearly always found in the halo, globular clusters, or the central bulge. population I stars. stars with significant amounts of atoms heavier than helium; relatively young stars nearly always found in the galactic disk.
Where are population 2 stars found in the Milky Way?
RR Lyrae variable stars and other Population II stars are found in the halos of spiral galaxies and in the globular clusters of the Milky Way system.
How are Population II stars different than population I stars?
Population I stars are younger stars found in the disk of the galaxy that contain lots of atoms heavier than helium (metals). Population II stars are older, metal-poor stars found in a galaxy's nuclear bulge, halo, and globular clusters.
Are population 2 stars older?
They are relatively old stars, with ages ranging from 2 - 14 billion years. Extreme Population II stars (the most metal poor) are found in the halo and the globular clusters; these are the oldest stars. Intermediate Population II stars are located in the bulge.
Is the sun a population 1 star?
Population I stars include the sun and tend to be luminous, hot and young, concentrated in the disks of spiral galaxies. They are particularly found in the spiral arms.
How much is the population?
World Population Clock: 7.97 Billion People (2022) - Worldometer.
Why are Pop II stars always red?
The brightest stars in a group of Population II stars are red giants. Red giants are stars in the process of dying. They have run out of hydrogen fuel in the core and swollen into cool red giants typically the size of the Earth's orbit around the Sun.
How does India's attempt at controlling population growth differ from China's quizlet?
How does India's attempt at controlling population growth differ from China's? C) India allows only rural families to have many children. How do advances in industrialization and urbanization cause a population rise? NOT disease immunity.
What questions should you ask to determine whether a population has passed through a demographic transition?
What questions should you ask to determine whether a population has passed through a demographic transition? Questions you should ask: Are the birthrates and death rates lower than they used to be? Did the birthrates and death rates used to be equally high?
What is a sharp decline in a population called?
population crash. a sharp decline that occurs due to an overshoot unless the species can switch to a new resource move to an area with more resources. population density. the number of individuals in a population found in a particular area or volume.
Where do population I stars occur?
All known Population I members occur near and in the arms of the Milky Way system and other spiral galaxies.
Who defined population I and II?
Populations I and II, in astronomy, two broad classes of stars and stellar assemblages defined in the early 1950s by the German-born astronomer Walter Baade.
What is population 1?
Population I consists of younger stars, clusters, and associations— i.e., those that formed about 1,000,000 to 100,000,000 years ago. Certain stars, such as the very hot, blue-white O and B types (some of which are less than 1,000,000 years old), are designated as extreme Population I objects. All known Population I members occur near and in the arms of the Milky Way system and other spiral galaxies. They also have been detected in some young irregular galaxies ( e.g., the Magellanic Clouds). Population I objects are thought to have originated from interstellar gas that has undergone various kinds of processes, including supernova explosions, which enriched the constituent matter. As a result, such objects contain iron, nickel, carbon, and certain other heavier elements in levels that approximate their abundance in the Sun; like the Sun, however, they consist mostly of hydrogen (about 90 percent) and helium (up to 9 percent).
