22.04.2023
NASA’s powerful James Webb Space Telescope captured amazing pictures of the moment two galaxies merged and created a new galaxy known as Arp 220. Our galaxy, the Milky Way, is expected to witness the same fate, but after about five billion years!
We certainly won’t be able to watch the Milky Way galaxy merge with Andromeda, its closest neighbour, a few billion years from now.
But thanks to a telescope James Webb NASA’s mighty space satellite (JWST, or Webb), we got a front row seat to witness an amazing galactic merger. The telescope has captured gorgeous images of two spiral galaxies located 250 million light-years away that merged 700 million years ago.
Arp 220, in the constellation of the Serpent (Serpens), is an ultraluminous galaxy as observed in infrared light (ULIRG). Scientists say it appears to shine with light that only comes from more than a trillion suns combined of the Space Telescope Science Institute (STScI)According to the NASA website.
In comparison, the institute says that the Milky Way galaxy does not shine with the same amount of brightness and that it has a luminosity that does not exceed the amount that comes from about 10 billion suns only, according to what was published by the “Fox Weather” website.
The Institute (STScI) says that the collision of two spiral galaxies and their merger to form the Arp 220 galaxy began 700 million years ago and sparked a huge explosion because both contained a very large number of stars, amounting to about 200 huge star clusters.
Arp 86 consists of two galaxies (NGC 7752) and (NGC 7753 – NGC 7753), which is the large spiral galaxy that dominates this image.
The new galaxy, which formed after the spectacular merger event, lies within the dusty region that extends about 5,000 light-years across. The institute added that this distance is about 5% of the entire Milky Way galaxy.
Over time, galaxy mergers that occurred millions of years ago and lasted for extremely long periods of time, even on cosmic time scales, are revealed.
Astronomers believe that the Arp 220 galaxy, which is surrounded by “spirals” like the Milky Way, and has similar tails that rotate at its outer edges, began to form after the merger 700 million years ago.
Previous observations showed the presence of about 100 “supernova” remnants (a massive explosion that occurs at the end of a star’s life cycle) in a region less than 500 light-years across. However, the institute said Hubble telescopeNASA’s satellite has revealed the cores of the parent galaxies, which are 1,200 light-years apart.
The STScI institute added that each of these galaxies has a rotating ring in which the stars line up and are clearly visible through infrared imaging, which made the James Webb telescope able to see and take pictures of them.
The Milky Way is supposed to come very close to the Andromeda Galaxy in the next four to five billion years, and the merger itself will extend over 10 billion years.
Emad Hassan