TNO's, Pluto and satellites stellar occultations: 2011

The predictions in this section are based on star catalogs produced by the Rio de Janeiro group, with star positions measured against the UCAC2 catalog.

The TNO's offsets (with respect to the Horizons JPL ephemerides) are measured by the same group during 2009. NB. Offsets are written in the upper right corner on charts.

The following diameters have been adopted for drawing the shadow paths:

body diameter (km) reference ephem. (JPL#)
Pluto 2350 DE413
Charon 1208 DE413/PLU017
Nix 88 DE413/PLU017
Hydra 72 DE413/PLU017
2002TX300 286 13
Eris 2400 28
Orcus 946 13
Quaoar 844 17
Haumea 1150 37
Makemake 1500 40
Varuna 500 19
Ixion 650 09
Sedna 1600 17
2003AZ84 686 11

Note that in a few cases, the shadow track is too far away from Earth to be visible on the maps. The prediction has been maintained, however, in case the event be eventually visible once astrometric update is available. The distance of closest approach and position angle of the body wrt the star are written at the bottom of the map, and allow one to derive the actual the shadow path in those cases.

Pluto and satellites offsets are given with respect to the DE413 barycentric ephemeris (while PLU17 is used for the satellites), and are based on a linear extrapolation of the offsets we (Paris group and Rio group) determined using Pluto and Charon occultations between 2005 and 2010. A linear extrapolation of this offset for 2011 has been applied at each date for Pluto, Charon, Nix and Hydra. These offsets should be refined prior to each event.

Note that the magnitudes given in the lower line are R* and K* (and not V* and R*, as usual), so that it is possible to point out very red stars that are unreachable in visible bands, but observable in J, H or K.

NB. a K magnitude close to 50 means that the star is not in the 2mass catalog, usually because it is too faint.

!!Note also that those magnitudes, with a star symbol "*", are normalized to a common shadow velocity of 20 km/sec !!!
We are using for that the following formula:

Magnitude* = Magnitude_actual + 2.5*log10[velocity/20 (km/sec)]

This is intended to point out very slow events, for which a longer integration time is possible.

Bruno Sicardy and the Rio group

Independent predictions are given on the following links:

IOTA European Section page
Leslie's Young page
MIT page