How is the Halo different from the rest of the galaxy?

The distinction between the halo and the main body of the galaxy is clearest in spiral galaxies, where the spherical shape of the halo contrasts with the flat disc. In an elliptical galaxy, there is no sharp transition between the other components of the galaxy and the halo.

What is the difference between halo and disk population stars in our galaxy?

In contrast to the thin and thick disks of disk galaxies, the halo generally has no net rotation and is supported almost entirely by velocity dispersion. The halo stars in the Milky Way are generally old, with most having ages greater than 12 billion years.

Why do the halo stars have different orbits than the stars in the spiral arms?

Halo stars have different orbits, so when they pass through the disk they have high speeds relative to the nearby disk stars.)

Are the stars in the Milky Way’s halo typically older or younger than the stars in the disk?

Population I stars contain more heavy elements than globular cluster and halo stars, are typically younger and found in the disk, and are especially concentrated in the spiral arms.

How many stars are in the halo of the Milky Way?

The Milky Way contains between 100-400 billion stars and at least that many planets. An exact figure would depend on counting the number of very-low-mass stars, which are difficult to detect, especially at distances of more than 300 ly (90 pc) from the Sun.

Is the sun in the disc of the Milky Way?

The sun orbits about 26,000 light-years from the black hole Sagittarius A*, roughly in the middle of the galactic disc. Travelling at the speed of 515,000 mph (828,000 kph), the sun takes 230 million years to complete a full orbit around the galactic center.

Is the sun in the bulge?

Answer: Yes, the Sun – in fact, our whole solar system – orbits around the center of the Milky Way Galaxy. The Milky Way is a spiral galaxy. We believe that it consists of a central bulge, 4 major arms, and several shorter arm segments.

How do stars orbit the Milky Way?

The stars in our galaxy are all orbiting in a nearly circular path around the center of the galaxy. They do this because the immense combined mass of the galaxy, most if it near the center, creates immense gravity that pulls all the stars in our galaxy into circular orbits.

How do stars orbit within the bulge of the Milky Way?

How do stars orbit in our galaxy? – Stars in the disk orbit in circles going in the same direction with a little up-and-down motion. – Orbits of halo and bulge stars have random orientations. We observe the star–gas–star cycle operating in Milky Way’s disk using many different wavelengths of light.

Where are population 2 stars found?

halos
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. Large numbers of these objects also occur in elliptical galaxies.

What do halo stars tell us about our galaxys history?

What do halo stars tell us about our galaxy’s history? The halo generally contains only old, low mass stars that have much smaller proportion of heavy elements than stars in the disk. Halo stars therefore must have formed early in the galaxy’s history, before the gas settled into a disk. How did our galaxy form?