Which of the following best describes dark matter?

Which of the following best describes dark matter? It is very large and invisible. Accretion is defined as: Gravity that pulls matter in a spiraling matter.

Why is our galaxy a spiral?

Astronomers believe that galaxies have spiral arms because galaxies rotate – or spin around a central axis – and because of something called “density waves.” A spiral galaxy’s rotation, or spin, bends the waves into spirals. Stars pass through the wave as they orbit the galaxy center.

Why does an elliptical galaxy look like one giant star?

An elliptical galaxy looks as if it is a giant star because it lacks the distinctive structure of a spiral galaxy, where the bulge is surrounded by a…

What is the major difference between an elliptical galaxy and a spiral galaxy?

Spiral galaxies contain both old and young stars, as well as interstellar matter, and have typical masses in the range of 109 to 1012MSun. Our own Galaxy is a large spiral. Ellipticals are spheroidal or slightly elongated systems that consist almost entirely of old stars, with very little interstellar matter.

Do elliptical galaxies have dark matter?

1 keV gaseous halos extending, in some cases, to well beyond 10re is strong evidence for the presence of extended dark matter in elliptical galaxies.

Why do the elliptical galaxies we see now have very very very little dust in them?

Most elliptical galaxies contain very little gas and dust because they had already formed.

What type of galaxy has the most dust?

Type c spiral galaxies

What Galaxy has the least amount of stars?

An ultra-faint collection of 1,000 stars orbiting the Milky Way is the most lightweight galaxy ever discovered, scientists say. The dwarf galaxy known as Segue 2 is bound together by a tiny clump of dark matter.

What galaxy type is full of gas and dust what type is not?

Elliptical galaxies contain very little gas and dust, and the gas that is present is very hot and diffuse. Consequently, there is no current star formation in elliptical galaxies. The stars in elliptical galaxies are old Population II stars.

Do irregular galaxies have gas and dust?

In general, irregular galaxies contain large amounts of gas and dust, and can exhibit a significant degree of star formation activity. The closest galaxy to the Milky Way happens to be an irregular galaxy called the Canis Major Dwarf.

What is a specific name of an irregular galaxy?

The Milky Way has two irregular “satellite” galaxies, called the Large and Small Magellanic Clouds.

How is a galaxy classified?

Galaxies are classified by shape. There are three general types: elliptical, spiral, and irregular. Our Milky Way Galaxy is a spiral galaxy. Some spiral galaxies are what we call “barred spirals” because the central bulge looks elongated – like a bar.

Which phrase best defines a galaxy?

Answer Expert Verified. Answer: Large collection of stars, gas, and dust held together by gravity.

What are two types of star clusters?

Star cluster, either of two general types of stellar assemblages held together by the mutual gravitational attraction of its members, which are physically related through common origin. The two types are open (formerly called galactic) clusters and globular clusters.

Which phrase best describes a star system?

What phrase best defines a star system? Stars appear brighter.