Just four months after its official opening, the ALMA observatory is already providing fascinating results. New observations of their dishes have provided astronomers with the best view obtained at the time of star formation wearing gas of a galaxy, and that leaves future generations of stars without the fuel to form and grow.
The shocking images, obtained for 16 of the 66 antennas of the ALMA (Atacama Large Millimeter / submillimeter Array) show huge molecular gas jets, dense and cold , fleeing the galactic disk center areas of star formation in the nearby Sculptor Galaxy. These results help explain the strange lack of massive galaxies in the Universe.
Sculptor Galaxy, also known as NGC 253 is a spiral type galaxy located in the southern constellation of Sculptor, at a distance of about 11.5 billion light years from our solar system . It is one of our closest neighbors intergalactic, galaxy and star formation burst nearest visible from the southern hemisphere.
“With the extraordinary resolution and sensitivity of ALMA, we can see clearly and for the first time, cold gas mass rallies being expelled by intense pressure shock waves created by young stars,” says Alberto Bolatto, University of Maryland (USA) and author of the paper.
“The amount of gas provides visible evidence that some growing galaxies expel more gas than they absorb . We may be seeing an actual example of a very common phenomenon occurring in the Universe early, “adds the scientist.
Why
grows or not a galaxy?
“We have been studying the region of bursts of star formation called NGC 253 and other nearby galaxies with bursts of star formation for almost ten years. But,” says Fabian Walker, a researcher at the Max Planck Institute for Astronomy, and one of the co-authors of the study, published in the journal ‘Nature’.
Experts have noted that the mass out of NGC 253 each year corresponds to at least 10 times the mass of the Sun, or even more . This escape limit the formation of young stars in the galaxy, because they need the gas as a “fuel” for their development, which may explain their smaller size. The expert estimates indicate that, based on this rate, the galaxy could run out of gas in 60 million years.
According to computer models, the oldest and most red galaxies should have far more mass and stars that we see today. This difference could be explained by the presence of galactic winds or gas leaks strip the galaxy of the material needed to form new stars .
galaxy formation, how they grow and, failing that, why not grow, are some of the points of interest in astronomy today. More studies using the full set of ALMA help us determine the ultimate fate of gas ejected by the wind , which will reveal if the winds caused by bursts of star formation recycle the material forming the stars or really take it by force to the environment.
ALMA is an international astronomy facility, is a partnership between Europe, North America and East Asia in cooperation with the Republic of Chile. Two decades of uninterrupted work, and more than 1,500 million, have resulted the most advanced astronomical observatory in the world , which is situated about 10 kilometers of the road from San Pedro de Atacama Toconao, in the middle of the driest place on the planet.
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