![]() ![]() ![]() They look red or yellow in color because they lack the hoty, young, blue stars found on the disks of spiral galaxies. They have little or no ongoing star formation. They usually contain very little dust or cool gas. Relatively rare giant elliptical galaxies are among the most massive galaxies in the universe, while small dwarf elliptical galaxies are much more common. ![]() Elliptical galaxies come in a wide range of sizes. Their axes look much like the bulge and halo of a spiral galaxy without a disk. Elliptical galaxies differ from spiral galaxies primarily in that they have only a halo component and lack a significant disk component. Spiral galaxies are the most common galaxy of the universe, comprising about 77% of all known galaxies 2. Lenticular galaxies occur with barred spirals and are classified as SB0. When a spiral galaxy has no arms, it's termed lenticular. The halo isa spherical shaped collection of old stars and clusters known as globular clusters that's found in the outer edge of the galaxy. The sun in our galaxy is located in one arm and its stars are created in this portion of the galaxy, which contains the most gas in the galaxy where it has rich blue stars. The arms of the spiral galaxy originate in the disk and are where new stars will form in a galaxy. The circular shape of the galaxy comprises the disk. The center of the galaxy is like a nucleus containing a sphere shaped bulge that houses old stars and is devoid of dust and gas. A spiral galaxy has a disk, a bulge, and a halo. are easily identified by observing three components common to all spiral galaxies. Other Spiral galaxies share these characteristics but in spiral galaxies with large bulges the orbits of bulge stars have more in common with the orbits of halo stars than with those of disk stars. The Milky Way's bulge stars exhibit a mixture of disk and halo. Disk stars orbit in the same plane and include stars of all ages and masses, while halo stars have randomly oriented orbits and are all old and low in mass. The galaxy's halo is considerably more difficult to see than its bulge and disk because halo stars are generally dim and spread over a large volume of space. The bulge merges smoothly into nearly invisible halo that can extend to a radius of more than 100,000 lys. Spiral galaxies have a thin disk and a central bulge. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |