I’m a theoretical physicist by training and inclination, but I’m not immune to awesome experiments or observatories. (Ahem.) Case in point: the new Atacama Large Millimeter/submillimeter Array (ALMA) in Chile. This array of 66 telescopes in the high Atacama Desert is particularly well suited to hunt for the earliest galaxies and stars in the Universe. Their early scientific results—timed for the official inauguration of the array this week—bear that out, with the measurement of the distances to several star-forming galaxies that formed less than 1.5 billion years after the Big Bang. What makes it even better? My article appeared today, which is Albert Einstein’s birthday, and ALMA scientists used gravitational lensing—an effect predicted from Einstein’s general theory of relativity—to locate these galaxies.
The galaxies of the Universe’s youth worked busily at making stars—that much is certain. However, what did those galaxies look like? How many were there, and how were they distributed in space and time?
Over such huge distances, those galaxies appear faint to us, so it’s only within the last decade or so that astronomers have been able to start obtaining a reasonable view of them. The newly inaugurated ALMA (Atacama Large Millimeter/submillimeter Array) is one of the most promising telescope arrays in the world for making observations of the early Universe. [Read more…]