Question

Which observation(s) is evidence that most of the stars, gas, and dust in our galaxy is in a thin disk? Select all that apply O Radio, X-ray,and gamma ray observations show gas in a band across the sky O Infrared observations show dust in a band across the sky O Individual stars appear in a band across the sky O Globular clusters appear in all directions on the sky Question 15 1pts Which observation(s) provide evidence that our galaxy formed from a gigantic collapsing gas cloud? Select all that apply The central bulge has a very high density of old stars, and very little gas m Younger stars have higher concentrations of elements heavier than helium 10 billion year old globular clusters orbit in random orientations Gas dust.and individual stars orbit in a plane and in the same direction 29

Answer 1

Lnfrared obsexyatrions lead to the coteer Conclusion ostot tue. sta YS , gasand dust in συγ IS rn a in disk Theyare usually mPsarel ijhnoor for an exeess Yoducthon beyond that emitted by the stay. Is o Globulor clusters apptras n all the direetions On the sky t ond lookin is also tha evi dence Hence option (2) and (u are corYeck Ceutral bulge has avz very hi dunsity old stars becausl and Very Citle of collapsingJas claud . As the °s cloud lapse densit Also Gas_ dust and individual st γ obit a plena ond the Some directon ch the direct pio is if ng Э0s cloud coll a p si Heuce opthon cj) and () Te corYect