Architectural projects on a galactic scale cannot be fast-tracked. Galaxies like our Milky Way take a long time to assemble and form. That, at least, was the conventional wisdom of astronomers until a few rather unsettling discoveries were made of late. A recent discovery by two astronomers from the National Centre of Radio Astrophysics, Pune, appears to throw one more challenge at astronomers.

If we could view our galaxy from the outside, it would appear to have a thin disc with some distinct spiral “arms” that are brightened by stars. These “arms” are like a traffic jam of stars in the galactic highway. Stars, including our Sun, go around the centre of the galaxy, and their paths often lead to a piling up of matter. This is similar to what happens behind a relatively slow-moving lorry on a highway. Gas in these regions is compressed by the “traffic jam”, which leads to further........

© Indian Express