The North Star Is Changing

Polaris is famed for its consistency, but the North Star we see today is brighter than it was in the 1800s. In fact, if historical records are correct, the star has gotten about 2.5 times brighter over the course of the past two centuries, researcher Scott Engle tells Space.com. What's more, it may be 4.6 times as bright as it was in ancient times, the site reports.

But the star is among those known as Cepheid variables, which means it pulsates—and in the early 1990s, researchers found that it was actually dimming. About a decade later, however, Engle and his team discovered that it was getting brighter once again. Engle's research can be difficult, Space.com notes, because it requires old technology that can be hard to find. The high-tech digital camera on Engle's telescope was actually too sensitive to accurately measure the star's brightness, so "we have to beg, borrow, and steal to find people who use older photoelectric equipment," he says. (More Polaris stories.)