Computer Ephemeris. Astrometric Pluto ephemeris. Explanations.

astrometric right ascension (hours, mimutes, seconds),
astrometric right ascension minus astrometric right ascension of previous date (seconds of time),
astrometric declination (degrees, minutes, seconds),
astrometric declination minus astrometric declination of previous date (seconds of arc),
horizontal parallax (seconds of arc),
apparent radius (seconds of arc),
geocentric distance (astronomical units),
geocentric distance minus geocentric distance of previous date (this number it is necessary to divide on 10⁸ to form number in astronomical units),
moment of upper culmination at Greenwich.

Astrometric positions is not an apparent ones. Two main differencies exists: reference system is J2000.0 and Pluto is referred as a star, but not Solar system body. Apparent places of Pluto you can see at 'Planets. Fundamental ephemeris. Pluto' page.