Turner is correct, his findings offer an explanation for why Polaris appears as bright as it does.
The current accepted distance to Polaris is 430 light-years. His research indicates that Polaris is 310 light-years away. Mary's University in Halifax, Nova Scotia, said Polaris was much closer than had been thought. Because al-Sufi also reported Polaris as third magnitude, ''it makes me believe that this could be correct,'' Dr. Engle also looked at the work of the Persian astronomer al-Sufi in the 10th century he made his own observations and corrected Ptolemy's errors. ''You're using someone's judgment calls, and these aren't scientific yet,'' Dr. Of course, maybe Ptolemy's eyesight was off. A change of a full magnitude would mean Polaris is 2.5 times as bright as it was 2,000 years ago. Today, Polaris is a second magnitude star. ranking stars from bright (1) to dim (6), a system still in use today. Magnitude is a scale devised by the Greek astronomer Hipparchus around 120 B.C. 140 listed Polaris as a third magnitude star. Ptolemy of Alexandria in his star catalog of A.D. In the 1500's, the astronomer Tycho Brahe recorded an even dimmer value.
In the 1800's, Polaris appeared to be 20 percent less bright. When he and Scott Engle, an undergraduate, checked older records, they found more surprises. Measurements over the past half century show it has brightened 10 percent. Even Polaris's average brightness has not remained the same, reported Dr.
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