Hello,
After considerable time wrestling with calculations, coordinates and settings, I was delighted to have recorded the trail of Nereid over a period of approx 100 minutes. Nereid was the outermost known moon of Neptune from its discovery in 1949 (by G. Kuiper) until 2002. The parent planet Neptune was positioned just outside the frame at lower left, to avoid saturation blooming of this (bright) magnitude 7.9 body.
Nereid was too far away from Voyager 2 to be properly imaged when the spacecraft visited the Neptune system in 1989. Photos sent back show only its highly irregular shape, and no surface features could be seen at the resolution available. Using the NASA (JPL) Horizons system, I generated an ephemeris for the 27th to 28th Sept at 1 hour intervals and then slewed the ‘scope to the coordinates generated by Horizons. The mean radius of Nereid is 170km and Horizons gave a magnitude of 18.72 for this small body.
Equipment details:
Celestron C9.25 F10 SCT.
Celestron F6.3 Reducer/Corrector (efl=1480mm).
SBIG ST7E ccd camera.
Tak EM200 mount.
Location details:
Brisbane, QLD, Australia.
Saturday, 27th Sept 2008.
20:07-21:33 AEST (UT+10h)
Capture details:
Captured using CCDSoft.
Five (5) sub frames of 20 minutes exposure each.
Auto guided using ST7 dual chip (TC211).
FOV 16x11 arc mins. Image scale 1.39 arcsec/pixel.
Processing details:
Dark and Flat reduction in MIRA AP.
Align and Stack in MIRA AP.
Final presentation in CS3.
Cheers
Dennis
Nereid Wiki details
http://en.wikipedia.org/wiki/Nereid_(moon)
Planetary Satellite Mean Orbital Parameters
http://ssd.jpl.nasa.gov/?sat_elem
Planetary Satellite Discovery Circumstances
http://ssd.jpl.nasa.gov/?sat_discovery
Horizons
http://ssd.jpl.nasa.gov/horizons.cgi