How did Harlow Shapley conclude that the sun was not in the center of the Milky Way galaxy?
Since the clusters assumed a spherical arrangement, it was logical to conclude that they would cluster around the centre of the Galaxy; from this conclusion and his other distance data Shapley deduced that the Sun lies at a distance of about 50,000 light-years from the centre of the Galaxy; the number was later …
Are halo stars older than disk stars?
They orbit the galactic center with many different inclinations, while disk stars all orbit in nearly the same plane. 6. How do we know that the halo stars are older, on average, than disk stars? A) We see evidence for new stars forming in the disk today.
Which kind of star is most likely to be part of the Halo spheroidal population?
Cards
| Term Stars that orbit on nearly the same plane | Definition disk stars |
|---|---|
| Term What kinds of objects lie in the halo of our galaxy? | Definition globular clusters |
| Term Which kind of star is most likely to be part of the spheroidal population? | Definition an M star |
Are there high mass halo stars?
The total mass of the halo is about 108 – 109 M sun, about 1% of which is the globular clusters, and the rest in field stars. So there’s not a lot of stuff in the stellar halo, but what is there holds a lot of information about the early history of the Galaxy!
Do elliptical galaxies have halos?
As their name suggests, elliptical galaxies are round or oval, with stars distributed fairly uniformly throughout. They have a bulge and halo, like spiral galaxies, but don’t have the flat disk of stars. The stars in ellipticals tend to be older.
Do elliptical galaxies have dark matter halos?
In conclusion, elliptical galaxies could have dark matter halos similar in mass and extent to those in spiral galaxies (Danziger, 1997), but the evidence is not so clear and it cannot even be completely rejected that they possess no dark halo at all.
Do elliptical galaxies contain dark matter?
Elliptical galaxies may very well have an additional baryonic dark component in the form of stellar remnants that may account for the variation with luminosity of the central mass-to-light ratio (Zepf & Silk 1996).
Why do elliptical galaxies have no gas?
The lack of interstellar gas is a relic from the ellipticals’ violent pasts. The motions of stars within these galaxies, along with sophisticated computer simulations, reveal that they are most likely the product of many galactic collisions.
Does the Galaxy have an end?
The distance between all its galaxies, planets, and stars is stretching all the time, like dots on a rubber band. It never ends, but it’s also constantly expanding. Scientists don’t think there is a true edge of the universe. This is called the edge of the observable universe.
How long will it take for the universe to end?
Vacuum decay might already have begun in some distant place. We won’t see it coming. Not to worry, though. As Mack counsels, whatever it looks like, the end probably won’t be nigh for at least 200 billion years.