From ground-based observations, we know that the stars in elliptical galaxies are older than about 3 billion years.
How old are the stars in a elliptical galaxy?
How old are the stars in the irregular galaxy?
The very bright stars in the picture, those with spikes around them, are stars in the foreground belonging to the Milky Way. The main body of SagDig is rich in gas, and contains many regions of active star formation. Indeed, the average age of the stars in the galaxy is a relatively young 4 to 8 billion years.
Are elliptical stars old?
Ellipticals are old. The stars that live within them are among the oldest in the universe. Unlike their spiral cousins, elliptical galaxies have shut down their star formation engines.
Do elliptical galaxies have stars?
Elliptical galaxies are made up of mostly old stars, and do not have much gas and dust. There is very little new star formation in these galaxies.
How old is the average 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 are in elliptical galaxies?
ten trillion stars The smallest are dwarf elliptical galaxies, which can be less than 10 percent of the size of the Milky Way. But ellipticals can also stretch to more than a million light-years across, and contain more than ten trillion stars.
How big is the average elliptical galaxy?
Elliptical galaxies vary greatly in both size and mass with diameters ranging from 3,000 light years to more than 700,000 light years, and masses from 105 to nearly 1013 solar masses. This range is much broader for this galaxy type than for any other.
Why are elliptical galaxies older?
Spiral galaxies are hotbeds of star formation, but elliptical galaxies aren't nearly as prolific because they contain less gas and dust, which means fewer new (and brighter) stars are born. The existing stars inside an elliptical galaxy tend to be older, giving off more red light than younger stars.
Are elliptical galaxies the oldest?
Elliptical galaxies, such as M87, are the oldest and roundest galaxies in the universe. Astronomers think these galaxies are formed in major mergers—dramatic collisions between galaxies that result in one massive galaxy being entirely consumed by another.