The mystery of the dead galaxies

Thanks to Hubble and other telescopes, astronomers are finding out why some giant galaxies quickly grow and stop starring when the universe is less than half of their current age.

Scientists have always wondered why lip-shaped galaxies tend to burn off energy when the new universe is about 3 billion years old.

Hubble helps decipher the mystery of giant dead galaxies - (Photo: NASA / ESA)

For ease of comparison, our Milky Way is 12 billion years old and continues to produce stars.

These galaxies are sometimes called "red and dead " galaxies, because their colors are different from those of the brothers who continue to "lay" in blue.

More surprising is that the dead galaxies are gigantic, similar to the current large spiral galaxies, but the stars are compressed in narrow spaces more than three times.

This means that the star density must be 10 times greater, according to Professor Sune Toft of the Niels Bohr Institute (Denmark).

Based on data collected by Hubble and other space telescopes, the researchers found that these galaxies tend to "live quickly and die young" quickly soon using up energy when they are about to 1 or 2 billion years old.

And these compressed galaxies work together to create giant lip galaxies, according to a report published in The Astrophysical Journal.