Astronomy in-class activity: monolithic collapse hypothesis, stellar populations

Astronomy 210 In-class activity 22 v.16.05.04, spring semester 2016
Cuesta College, San Luis Obispo, CA

Students find their assigned groups of three to four students, and work cooperatively on an in-class activity worksheet to discuss different metallicities and ages of stars in the monolithic collapse hypothesis of the Milky Way.

1 comment:

Patrick M. Len said...

Cuesta College
In-class activity 22
Astronomy 210 spring semester 2015 section 30676
Sample responses to 2(b):

"Both statements [M & H] but don't necessarily explain the answer. Most of the hydrogen is in the older halo stars, that did not absorb/develop metals heavier than hydrogen."

"[Statement used: M.] Massive main-sequence stars are more capable of star formation as the halo stars have already given off most of their metals and hydrogen. So as the stars expand and become bigger, they give off their metals and hydrogen."

"[Statement used: H.] Halo stars are metal-poor thus have more hydrogen so most of the hydrogen in the Milky Way is in the halo."

"[Statement used: H.] Most of the hydrogen is in halo stars, but there is some in disk stars, too. There is more hydrogen in halo stars than in disk stars."

"Statement H supports us more because it is telling us that halo stars are mostly made of hydrogen so that is where most of the hydrogen in the Milky Way is today."

"[Statement used: H.] Older stars are still made of hydrogen, whether they contain metals or not, so there is still hydrogen in the halo."

"[Statements used: M & H.] Most of the hydrogen is in the disk as stars, while some of the older hydrogen that got left behind is in the halo."

"Statement H best answers the question as newer stars in the Milky Way. Newer stars have less hydrogen and more metals while older stars, that are in the halo, have more hydrogen than metals. Statement M really didn't answer the question."

"[Statement used: H.] Halo stars haven't yet been pulled into the disk, and are therefore composed mostly of hydrogen."

"Statement H better explains where interstellar hydrogen is. Halo stars are older, thus containing more hydrogen than metal. While disk stars are newer, therefore containing more metals."

"[Statement used: H]. The halo stars haven't been pulled into the disk. The halo stars have more hydrogen."