Discovery of the "pearl chain" in distant colliding galaxies

Discovery of :

the "pearl chain" in distant colliding galaxies

An international group of astronomers, through observations of

the Hubble Space Telescope, found that collisions of galaxies

contrary to popular belief, generate new generations of stars, not destruction.

According to NASA :

on Thursday :

February 8, the Hubble Space Telescope focused on 12 interacting galaxies

with long, tidal tails in the form of a series of pearls

consisting of gas, dust and a large number of stars.

Hubble's remarkable accuracy and sensitivity to UV light revealed 425 newborn

stellar clusters along these tails, which look like strands of ornamental lights.

Each star cluster 

contains up to 1 million newborn blue stars.

Stellar coins are a group of stars associated with each other by gravity.

The star clusters found in "tidal tails" have been known for decades.

These tails occur when galaxies interact

with tidal forces pulling long streams of gas and dust.

A team of astronomers used a range of new observations and archival data to

obtain the ages and lumps of star clusters in the tails. They found these clusters to

be very small, only 10 million years old. 

1. They appear to form
2. at the same rate along tails
3. spanning thousands of light years.

Lead author Michael Rodrack of Randolph Macon College in Ashland

Virginia, said:

• "It's a surprise to see so many small objects in the tails.

• This tells us a lot about the efficiency of cluster formation.

• Using tidal tails, new generations of stars that might

not otherwise exist will be built. "

The tails appear to take the galaxy's spiral arm and extend it into space.

The outer part of the arm is drawn between a pair of interacting galaxies.

Prior to mergers, galaxies were rich in dust clouds of molecular hydrogen

which may have remained inert. But the clouds crowded and bumped

into each other during the meeting.

This led to :

hydrogen pressure to

the point that triggered a firestorm of star birth.

Stars in the form of a series of pearls may have been more common in

the early universe when galaxies repeatedly collided with each other.

These nearby galaxies observed by Hubble document

what has happened for a long time

and are therefore laboratories to look at the distant past.