Pluto Occultation September 27, 2007

The northern limit, centerline, and southern limit of Pluto's shadow are shown by the three lines across the globe pictured above. The shaded area represents where the sun is more than 12 degrees below the horizon.

P507 Prediction

(as of: 2007 07 20)

Geocentric Mid-time (yyyy month dd hh:mm:ss) 2007 September 27 14:48:20± 00:00:57 UT
Minimum Geocentric Separation 0.390± 0.023 arcsec
Position Angle (Pluto relative to the star; measured north through east) –152.363 degrees
Geocentric Velocity 11.2 km/sec
Prediction Version P507-AST-3.0


Reference star position:
(UCAC2, at epoch of event)
RA (h:m:s; J2000) Dec (d:m:s; J2000) UCAC Mag1
P507 Catalog2 17 44 38.3944 ±0.0198 –16 46 35.447 ±0.0321 8.7
P507 Corrected           -------           -------  

1The UCAC bandpass (579-642nm) is between V and R.

2UCAC2, at epoch of event.

Offsets from Reference Position/Ephemeris3
Body RA (arcsec) Dec (arcsec) Notes


          -------           -------           -------

–0.0148± 0.0220

+0.011± 0.021 From 237 strip scans and 89 USNO-61inch Telescope frames.

3All "offsets" are defined in the ("corrected" – "reference") or ("observed" – "calculated") sense. The offsets should be added to reference positions to get the measured positions, which we use to calculate the prediction.

4JPL Horizon's ephemeris (System DE413 - Pluto source file: PLU013; Earth center source file: DE405).


Archive of all P507 occultation predictions based on alternate sources of data, including past predictions

Results of Previous Occultations

Results of the 2006 Pluto occultation are described and compared with results of the 1988 and 2002 occultation in the publication, Changes in Pluto's Atmosphere: 1988-2006


Last updated by Carlos A Zuluaga ( 2007-07-20 08:45

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