ALMA looks at the farthest dusty galaxies seen, Astronomers who use the Atacama Big Millimeter / Submillimeter Array (ALMA) have discovered the light of a giant galaxy that seen only 970 million years after the Big Bang.
This galaxy, called MAMBO-9, is the dustiest star-forming galaxy ever without the help of a gravitational lens.
The flour star galaxy is the most powerful star garden in the universe. They form stars at speeds of several thousand times higher than solar mass per year (the speed of star formation from our Milky Way is only three solar masses per year) and contain large amounts of gas and dust.
Such galactic monsters are not thought to have formed in the early history of the universe, but astronomers have discovered some of them as seen when the cosmos was less than a billion years old.
Because of their extreme behavior, astronomers believe that this dusty galaxy plays an important role in the development of the universe. But finding them is easier than doing it.
Light from MAMBO-9 captured ten years ago by co-author Manuel Aravena with Max Planck Millimeter BOlometer (MAMBO) from a 30-meter IRAM telescope in Spain and the Plateau de Bure interferometer in France.
But, these observations are not sensitive enough to reveal galactic distances. “We doubt if it’s real because we can’t find it with another telescope. But if it’s real, it must be very far away.
Because of the sensitivity of ALMA, Casey and his team were able to determine the distance from MAMBO-9. “We found galaxies in the new ALMA study designed to identify dust-forming galaxies in the early universe.
Light from distant galaxies is often blocked by other galaxies that are closer to us. The galaxies in the foreground act like gravitational lenses: they bend the light of the galaxy further.
This lens effect makes it easier for the telescope to find distant objects (so ALMA can see the galaxy SPT0311-58). But it also distorts the image of the object and makes it difficult to understand its details.
In this study, astronomers see MAMBO-9 without a lens so they can measure their mass. The total mass of gas and dust in the galaxy is huge: ten times more than all the stars in the Milky Way. That means it will still build most of the stars, “Casey explained. The galaxy is in two parts and has joined.
Casey hopes to find more dusty galaxies in the ALMA study which gives an idea of how common they are, how these massive galaxies formed so early in the universe, and why they are so dusty.
Officer of the National Science Foundation Program for NRAO and ALMA. Although it is difficult to explain galaxies of that size at the beginning of the history of the universe, inventions like these allow astronomers to develop a better understanding and ask more questions about the universe.
Light from MAMBO-9 takes about 13 billion years to reach the ALMA antenna (the universe is around 13.8 billion today).
This means we can see what galaxies have been like in the past. Today, galaxies maybe even bigger and contain a hundred times more stars than the Milky Way, which located in large clusters of galaxies.