O aglomerado estelar Fênix, uma das maiores estruturas do universo, gera 740 estrelas por ano, e está localizado acerca de 5,7 bilhões de anos-luz da Terra, e deve criar cerca de duas estrelas por dia, muito mais que a quantidade criada por outros aglomerados semelhantes.
Oficialmente denominado SPT-CLJ2344-4243, o aglomerado recebeu o apelido de Fênix numa referência ao pássaro mitológico que renascia das cinzas dos mortos.
Com base em observações do Observatório Chandra de Raios X, do Telescópio do Polo Sul da Fundação Nacional Científica dos EUA e de outros oito observatórios, pesquisadores disseram que o centro do aglomerado Fênix estava relacionado à criação de aproximadamente 740 estrelas ou massas solares por ano. para se ter uma ideia o aglomerado Perseu forma estrelas a um ritmo 20 vezes menor.
Aglomerados como este devem conter milhares de galáxias.
Buracos negros supermassivos na galáxia central de aglomerados há muito eram associados a baixas taxas de formação estelar, porque sugam energia do sistema, impedindo o resfriamento dos gases, necessário à criação de estrelas. Mas pesquisadores disseram que a "criação massiva" de estrelas observada em Fênix indica que o buraco negro de sua galáxia central não conseguiu interromper um fluxo de resfriamento extremamente potente.
"Estrelas estão se formando no aglomerado Fênix ao mais alto ritmo já observado para o centro de um aglomerado galáctico," informou o Centro de Astrofísica Harvard-Smithsonian. "O objeto é também o mais poderoso gerador de raios X entre os aglomerados conhecidos, e um dos de maior massa. Os dados também sugerem que a taxa de resfriamento de gás nas regiões centrais do aglomerado é a maior já verificada".
Phoenix galaxy cluster, one of the largest structures in the universe, creates a massive 740 stars a year
A massive galaxy cluster, one of the largest structures in the
universe, has been discovered about 5.7bn light years from Earth and
credited with forming about two stars a day, much higher than other such
clusters.
Observations of the galaxy cluster may force astronomers to rethink how such colossal structures and galaxies that inhabit them evolve.
Known officially as SPT-CLJ2344-4243, the cluster has been nicknamed Phoenix after the mythological bird that rose from the dead.
Based on observations from Nasa's Chandra x-ray observatory, the US National Science Foundation's South Pole telescope and eight other observatories, researchers said the centre of the Phoenix cluster had been linked to the creation of about 740 solar masses or stars a year. By comparison, the Perseus cluster forms stars 20 times slower.
Huge clusters like Phoenix were thought to host thousands of galaxies.
Supermassive black holes in the central galaxy of a cluster have long been associated with low observed star formation rates, as they pump energy into the system and prevent the cooling of gases needed for the creation of stars. But researchers said the "massive starburst" seen in Phoenix, suggested its central galaxy's black hole had failed to interfere with an extremely strong cooling flow.
"Stars are forming in the Phoenix cluster at the highest rate ever observed for the middle of a galaxy cluster," the Harvard-Smithsonian Centre for Astrophysics said in its press release. "The object also is the most powerful producer of x-rays of any known cluster and among the most massive. The data also suggests the rate of hot gas cooling in the central regions of the cluster are the largest ever observed".
Observations of the galaxy cluster may force astronomers to rethink how such colossal structures and galaxies that inhabit them evolve.
Known officially as SPT-CLJ2344-4243, the cluster has been nicknamed Phoenix after the mythological bird that rose from the dead.
Based on observations from Nasa's Chandra x-ray observatory, the US National Science Foundation's South Pole telescope and eight other observatories, researchers said the centre of the Phoenix cluster had been linked to the creation of about 740 solar masses or stars a year. By comparison, the Perseus cluster forms stars 20 times slower.
Huge clusters like Phoenix were thought to host thousands of galaxies.
Supermassive black holes in the central galaxy of a cluster have long been associated with low observed star formation rates, as they pump energy into the system and prevent the cooling of gases needed for the creation of stars. But researchers said the "massive starburst" seen in Phoenix, suggested its central galaxy's black hole had failed to interfere with an extremely strong cooling flow.
"Stars are forming in the Phoenix cluster at the highest rate ever observed for the middle of a galaxy cluster," the Harvard-Smithsonian Centre for Astrophysics said in its press release. "The object also is the most powerful producer of x-rays of any known cluster and among the most massive. The data also suggests the rate of hot gas cooling in the central regions of the cluster are the largest ever observed".
Nenhum comentário:
Postar um comentário