There's a bit of a historical mystery surrounding the star Theta Eridani. Ptolemy in the second century A.D. and al-Sufi in A.D. 964 both recorded Theta Eridani as one of the 13 brightest stars in the sky. Hipparchus may
To ancient astronomers, Theta Eridani was brighter for 1,000 years—now we know why
There's a bit of a historical mystery surrounding the star Theta Eridani. Ptolemy in the second century A.D. and al-Sufi in A.D. 964 both recorded Theta Eridani as one of the 13 br
