Is our galaxy elliptical or spiral?
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 statement accurately describes irregular galaxies?
Which statement accurately describes irregular galaxies? Irregular galaxies contain many newly-formed stars.
Which phrase describe an irregular galaxy?
An irregular galaxy is a galaxy that does not have a distinct regular shape, unlike a spiral or an elliptical galaxy. Irregular galaxies do not fall into any of the regular classes of the Hubble sequence, and they are often chaotic in appearance, with neither a nuclear bulge nor any trace of spiral arm structure.
What defines a galaxy?
Galaxies are sprawling systems of dust, gas, dark matter, and anywhere from a million to a trillion stars that are held together by gravity. Nearly all large galaxies are thought to also contain supermassive black holes at their centers.
What is the difference between elliptical and lenticular galaxies?
For example, a rough criterion for distinguishing between lenticular and elliptical galaxies is that elliptical galaxies have v/σ < 0.5 for ε = 0.3. The motivation behind this criterion is that lenticular galaxies do have prominent bulge and disk components whereas elliptical galaxies have no disk structure.
Why do elliptical galaxies appear yellow or red?
Elliptical galaxies are reddish to yellowish in color because they contain mostly old stars. Most elliptical galaxies contain very little gas and dust because they had already formed.
What does an elliptical galaxy look like?
These galaxies look very different from spiral galaxies. Instead of spiral arms, elliptical galaxies are just big clumps of stars. There is very little gas and dust. An image of elliptical galaxy, IC 2006 taken with the Hubble Space Telescope. The stars form a cloud looking galaxy rather than grouping together in arms.
Why are there so few young stars in elliptical galaxies?
There is very little dust in an elliptical galaxy, which is one of the reasons why there are few younger stars. One of the brightest galaxies in our sky, Centaurus A, is an elliptical galaxy. Although it was once thought to be true, elliptical galaxies actually don’t evolve into spiral galaxies.
What is a dwarf elliptical galaxy?
These are called “dwarf elliptical”. Elliptical galaxies can have as little as ten million stars in them, or as much as one hundred trillion stars in them – they vary greatly! They are generally made up of a lot of older stars that have a relatively low mass.
How old is the oldest elliptical galaxy?
Elliptical galaxies are often some of the oldest galaxies in our night sky – they tend to range anywhere between 7 billion and 10 billion years old. How many stars can an elliptical galaxy have? There are elliptical galaxies in our universe that have trillions of stars, some of them even having more than one hundred trillion.