Knowledge of the universe is constantly expanding as more observations bring new information to light. What we knew yesterday may turn out to have been wrong tomorrow. A recent instance of this is the size of our own galaxy. For years astronomers have known that the Milky Way is approximately 100,000 light years across. A recent article that can be seen here reports that new observations put the actual size at 150,000 light years and possibly larger.
What they have discovered is that the galaxy is not simply a spiral on a flat plane. It is wavy or “corrugated” as they put it, with high and low sections stated forbes.com. From the Earth’s perspective of observation some of these are easier to see and led to the original estimate of its size. Data taken in 2002 seemed to show a bulging ring of stars around the Milky Way. When they recently re-evaluated the observations they realized what they were actually seeing was the continuing wavy form of the galaxy. They have further identified four ripples radiating out from the galactic center that seem to confirm their conclusions.