Mark Twain once said, “It ain’t what you don’t know that gets you into trouble. It’s what you know for sure that just ain’t so. ”

The history of science provides many entertaining examples. So today, Abraham Loeb at Harvard University in Cambridge, scour the history books for examples from the world of astronomy.

It turns out that the history of astronomy is littered with ideas that once seemed incontrovertibly right and yet later proved to be bizarrely wrong. Not least among these are the ancient ideas that the Earth is flat and at the centre of the universe.

But there is no shortage of others from the modern era. “A very common ﬂaw of astronomers is to believe that they know the truth even when data is scarce,” says Loeb.

To make his point, Loeb has compiled a list of ten modern examples of ideas that were not only wrong but also significantly held back progress in astronomy “causing unnecessary delays in ﬁnding the truth”.

Here are three of them: