Star clusters or star clouds are groups of stars. Two types of star clusters can be distinguished: globular clusters are tight groups of hundreds or thousands of very old stars which are gravitationally bound, while open clusters, more loosely clustered groups of stars, generally contain fewer than a few hundred members, and are often very young. Open clusters become disrupted over time by the gravitational influence of giant molecular clouds as they move through the galaxy, but cluster members will continue to move in broadly the same direction through space even though they are no longer gravitationally bound; they are then known as a stellar association, sometimes also referred to as a moving group.
Star clusters visible to the naked eye include Pleiades, Hyades and the Beehive Cluster.
Globular clusters, or GC, are roughly spherical groupings of from 10,000 to several million stars packed into regions of from 10 to 30 light years across. They commonly consist of very old Population II stars—just a few hundred million years younger than the universe itself—which are mostly yellow and red, with mass just less than two solar masses. Such stars predominate within clusters because hotter and more massive stars have exploded as supernovae, or evolved through planetary nebula phases to end as white dwarfs. Yet a few rare blue stars exist in globulars, thought to be formed by stellar mergers in their dense inner regions; these stars are known as blue stragglers.
A child 5 years of age stared into the sun
She stared into the bright lights so long it
Burnt a hole in her mind and branded her eyes
It imprinted upon her soul, mysteries of both young and old
And then she'd close her eyes tight to feel the darkness
She's a dancing girl, dancing girl
She danced so fast, so fine
She danced around with her eyes shut
To see the stars in her mind
A spinning jupiter, a spinning mars
She herself was just a singing star
A breathing constellation
Cause she's a bright point of light
Traveling through the skies of her mind
Oh and how she knew the stars
And the map of the human heart
For long lengths of time, she'd stay in her mind
And follow roads back, ancient tracks and primitive times
When giant birds lifted themselves of
Starry wings to burn white, fiery silhouettes into the night sky
She's a dancing girl, dancing girl
She danced for them
And she followed all the lines back
To where they did begin
She saw her mother in pegas wings'
She felt her father in a scorpial sting
A genetic constellation
Cause she was a bright point of light
Traveling through the skies of her mind
Oh and how she knew the stars
And the map of the human heart
She saw bursting flowers made of lucride stone
Shooting stars who songs sang to her bones
She saw stories her grandfather used to tell
His flesh was frozen was frozen and kept so well
And a clear meeting of words, but pictures to
Tell her what she knew she needed to hear
She's a dancing girl, dancing girl
She danced so fast, so well
And she danced until her knees got weak
And all resistance fell
And all the walls, they came tumbling down
She stood eyes open, back on the ground
Wiser, full of glory
She was a bright point of light
Traveling through the skies of her mind
Oh and how she knew the stars