What are population 1 and population 2 stars?
Intermediate Population I stars (like the Sun) are located through the disk. They are slightly less metal rich. Population II stars are metal poor stars; they contain about 0.1 percent metals. Extreme Population II stars (the most metal poor) are found in the halo and the globular clusters; these are the oldest stars.
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.
What is meant by the term population I stars?
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.
What explains the metallicity difference between Population I and Population II stars?
What explains the metallicity difference between population I and population II stars? Population II stars formed when the abundance of elements heavier than hydrogen and helium was low. Stars that form from the enriched ISM will have higher levels of metallicity.
What is the difference between Population I and Population II stars describe each and identify their differences?
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.
Which type of galaxy contains the most Population II stars?
elliptical galaxies
In fact, elliptical galaxies contain primarily old, red stars (also known as Population II stars). Elliptical galaxies vary widely in size. Both the largest and the smallest known galaxies are elliptical. Very large elliptical galaxies can reach 300 million light years in diameter.
How is star metallicity measured?
A different way of measuring a star’s chemical composition is by the Iron(Fe)-to-Hydrogen(H) ratio: for the sun, so that for every Iron atom there are 20,000 Hydrogen atoms. Question: What does it mean to have a metallicity: [Fe/H] = +1.0.
Why do we think Population II don’t have any heavy metals?
Since light metals are produced primarily in Type II supernova explosions (the explosions of massive stars which have lifetimes of only a few million years), while the heavier elements can only be produced in Type Ia supernova explosions (the explosion of a much older white dwarf in a binary system), the relative lack …
What distinguishes the different stellar populations in our galaxy?
We now know that the populations differ not only in their locations in the Galaxy, but also in their chemical composition, age, and orbital motions around the center of the Galaxy.
What is a characteristic of Population II stars?
Population II stars tend to be found in globular clusters and the nucleus of a galaxy. They tend to be older, less luminous and cooler than Population I stars. They have fewer heavy elements, either by being older or being in regions where no heavy-element producing predecessors would be found.