#############################################################################
version1/ used until October 2013
TNO ephemerides with old version of ephemeris computation.
The weight of observations is given by:
- Astdys (MPC): given by Astdys
- ESO: weight = 90mas
- OPD: weight = 180mas
- Pic du Midi: weight = 180mas
- Fraser: weight = 300mas
- Unknown: weight = 300mas
version2/ used from 25 October 2013 to 18 September 2014
TNO ephemerides with new version of ephemeris computation.
weight is given by sqrt(bias^2+sigma^2/N) with N, the number
of observations per night
The bias is given by:
- Astdys (MPC): depending on the catalogue
- WFI:
ESO bias = 75mas
OPD bias = 150mas
PdM bias = 150mas
other bias = 300mas
- UCAC/other
ESO bias = 150mas
OPD bias = 225mas
Other bias = 300mas
- Fraser: bias = 300mas
- Unknown: bias = 300mas
The sigma is given by:
- Astdys (MPC): weight given by Astdys
- ESO: sigma = 75mas
- OPD: sigma = 150mas
- Pic du Midi: sigma = 300mas
- Fraser: sigma = 300mas
- Unknown: sigma = 300mas
version3.1/ used from 19 September 2014 to 25 November 2014
TNO observations are not merged into night anymore.
Each observation now appears and the weight given to each
observation is sqrt(bias^2*N+sigma^2) with N, the number
of observations per night.
The bias is given by:
- Astdys (MPC): depending on the catalogue
- WFI:
ESO bias = 75mas
OPD bias = 150mas
PdM bias = 150mas
other bias = 300mas
- UCAC/other
ESO bias = 150mas
OPD bias = 225mas
Other bias = 300mas
- Fraser: bias = 300mas
- Unknown: bias = 300mas
The sigma is given by:
- Astdys (MPC): weight given by Astdys
- ESO: sigma = 75mas
- OPD: sigma = 150mas
- Pic du Midi: sigma = 300mas
- Fraser: sigma = 300mas
- Unknown: sigma = 300mas
version3.2/ used since 25 November 2014
TNO observations are not merged into night anymore.
Each observation now appears and the weight given to each
observation is sqrt(bias^2*N+sigma^2) with N, the number
of observations per night.
The bias is given by:
- Astdys (MPC): bias = 300mas
- WFI:
ESO (809) bias = 75mas
OPD (874) bias = 150mas
PdM (586) bias = 150mas
CA (493) bias = 150mas
SN (J86) bias = 150mas
LH (I95) bias = 150mas
MLP (Z20) bias = 150mas
LLP (J13) bias = 150mas
other bias = 300mas
- UCAC/other
ESO (809) bias = 150mas
OPD (874) bias = 225mas
PdM (586) bias = 225mas
CA (493) bias = 225mas
SN (J86) bias = 225mas
LH (I95) bias = 225mas
MLP (Z20) bias = 225mas
LLP (J13) bias = 225mas
other bias = 300mas
- Fraser: bias = 300mas
- Occultation bias = 0mas
- Unknown: bias = 300mas
The sigma is given by:
- Astdys (MPC): weight given by Astdys
- ESO (809) sigma = bias
- OPD (874) sigma = bias
- PdM (586) sigma = bias
- CA (493) sigma = bias
- SN (J86) sigma = bias
- LH (I95) sigma = bias
- MLP (Z20) sigma = bias
- LLP (J13) sigma = bias
- Fraser: sigma = 300mas
- Unknown: sigma = 300mas
- Occultation sigma = 40mas/75mas
version4/ since 7 December 2016
identical to version 3.2 with new exception for offset obs
reduced with DR1
bias = 40 + 20 * |yr-2015| (mas)
sigma = 20 + 20 * |yr-2015| (mas)
Version2 from October 2013, 17 to 25, observations from Pic du Midi have bias
and sigma of 150 mas. It only produces minor changes in orbit.
############################ 2014.11.25 #####################################