Every nakshatra is quartered. The four padas, literally feet, are the smallest unit jyotisha divides the ecliptic into and the reason the system can say anything finer than thirteen degrees. Purva Bhadrapada runs from 320 degrees 00 minutes to 333 degrees 20 minutes of the sidereal circle, and its four padas are three degrees twenty minutes each: the first from 20 degrees 00 minutes of Aquarius, the second from 23 degrees 20 minutes of Aquarius, the third from 26 degrees 40 minutes of Aquarius and the fourth from 0 degrees 00 minutes of Pisces. The Moon crosses a single pada in roughly six hours, so a birth an afternoon apart can fall in two of them.
The arithmetic hides a coincidence that is not one. Twenty seven nakshatras of four padas make one hundred and eight divisions of the zodiac, and the navamsha, the ninth-part chart that jyotisha treats as the most important of all the divisional charts, also cuts the circle into one hundred and eight. They are the same cut. A pada is a navamsha, and naming the pada names the navamsha sign without any further calculation. The four padas of Purva Bhadrapada fall in Aries, Taurus, Gemini and Cancer in that order.
Two cautions attach to those degrees. They are sidereal, measured from a fixed point among the stars rather than from the equinox, so they depend on the ayanamsha chosen to locate that point; the Lahiri, Raman and Krishnamurti values differ by up to about a degree, which is a fifth of a pada and enough to move a chart across a boundary. And the equal arcs are a scheme laid over the sky rather than a description of it: the star the nakshatra is named for sits somewhere inside its arc rather than filling it, and for several nakshatras that identification is itself disputed.