What is the typical age for globular clusters?

What is the typical age for globular clusters?

Globular clusters in the Milky Way Galaxy prove to be nearly as old as the universe, averaging perhaps 14 billion years in age and ranging between approximately 12 billion and 16 billion years, although these figures continue to be revised.

How old are the globular clusters near the Milky Way?

There are about 150 known globular clusters in the Milky Way galaxy, according to Georgia State University’s HyperPhysics website. Most are estimated to be at least 10 billion years old, and contain some of the oldest stars in the galaxy.

Which star cluster is the youngest?

Within age uncertainties, Segue 3 appears to be the youngest globular cluster so far known in the halo, or in the whole Galaxy altogether.

What is the oldest globular cluster?

A team of astronomers using the Gemini-South telescope has discovered one of the oldest stellar clusters in the Milky Way. The team’s results date the globular cluster, named HP 1, at about 12.8 billion years, making its stars among the oldest ever found in our Galaxy.

How are globular clusters distributed in our Milky Way galaxy?

How are globular clusters distributed in our Milky Way Galaxy? Mostly in a large spherical halo surrounding the flat disk of the Galaxy. Dust in the space between stars builds up over large distances and blocks the light of stars behind the dustier parts of the Milky Way.

How are globular clusters distributed around galaxies?

A large majority of the Milky Way’s globular clusters are found in the celestial sky around the galactic core. Assuming a roughly spherical distribution of globular clusters around the galaxy’s center, he used the positions of the clusters to estimate the position of the Sun relative to the galactic center.

How do you determine the age of a cluster?

As a cluster ages, the mass of the main-sequence turnoff stars decreases. By determining the mass of the main-sequence turnoff stars, we get the age of the cluster. The cluster age equals the main-sequence lifetime of the turnoff stars.

How do you measure the age of a globular cluster?

By placing the stars in a globular cluster on a Hertzprung-Russell diagram, astronomers can determine the cluster’s age by looking at the main sequence turnoff point and comparing it with models of stellar evolution.

How are globular clusters distributed?

Globular clusters are typically located in the outer regions (the halos) of galaxies, and our Milky Way galaxy has about two hundred of them. The distribution of globular clusters around a galaxy holds therefore clues to their origins and to the history of the host galaxy.

How do you determine the age of a star cluster?

Both a cluster’s age and its distance can be derived from such a diagram. The age comes from determining the location of the tip of the main sequencewhich is defined as the last star still on the main sequence. The main sequence lifetime of this star is then taken to be the cluster’s age.

What is the difference between globular clusters and open clusters?

— globular clusters are very old, ~1010 yrs, while open clusters are young. — open clusters are always found close to the plane of the Milky Way, may not be bound by their own gravity, typically have a 1000 members, frequently found in association with interstellar matter.

How do globular clusters form a halo around the Galaxy?

Globular clusters form a halo around the galaxy: In 1908 the period-luminosity relationship for RR Lyrae stars, commonly found in globular clusters, wasdiscovered by Henrietta Leavitt. She was studying these variable stars in the Large Magellanic Cloud so she could assume that her stars were all at the same distance.

How far is the center of the Milky Way?

Shapley observed a number of globular clusters and discovered that the center of the Milky Way is some distance (now known to be 8.5kpc) from the Sun. Shapley’s Method: