This page presents the prediction of occultations by selected TNOs and Centaurs for 2018. These predictions are made in the framework of Lucky Star project (led by B. Sicardy) and in collaboration with groups from Paris, Meudon, Granada and Rio.
For specific campaigns, you can have a look to F. Braga Ribas page.
Information about the predictions can be found in Assafin et al. (2010) for Pluto system predictions, Assafin et al. (2012) for the TNO predictions, Camargo et al. (2014) for TNO and Centaur predictions. Ephemerides of the selected objects come from Desmars et al. (2015) and they are regularly updated thanks to observations from Minor Planet Center and our own observations made at ESO, Pic du Midi, Calar Alto, Sierra Nevada and Observatorio do Pico dos Dias.
As from 25 April 2018, the predictions make use of Gaia DR2 (Gaia Collaboration, 2018) for the positions of the star and the proper motion. Before 25 April 2018, predictions were done with Gaia DR1 (Gaia Collaboration, 2016) for the positions of stars and the Gaia-PS1-SDSS (GPS1) Proper Motion (Tian et al. 2017) and UCAC5 (Zacharias et al. 2017) catalogues for estimated proper motions.
A special page for the occultation by Pluto on 15 August is available on that link
IMPORTANT: If you plan to observe one of these predicted events, please contact J. Desmars .
(East-Asia, Europe & North Africa, Oceania, Southern Africa, North America, South America)
Information about the table:
- Predictions can be filtered by date, object, zone, and/or magnitude;
- The G* magnitude is the G magnitude (from Gaia), normalized to a body moving at 20km/s in order to enhance very slow events (G* = G + 2.5 log (v/20) with v is the velocity in the skyplane (km/s));
- Zones are defined approximately as large areas covering East-Asia, Europe & North Africa, Oceania, Southern Africa, North America, South America according to the map;
- By clicking on one map, you will find a specific page of the event, with the prediction map, occultation circumstances and the field of view with the occulted star.
- As the table may be long to display, events with a solar elongation greater than 20° are considered and filters on date and magnitude are initially applied. Do not hesitate to change the filters to see all the events.
Information about the maps:
- The straight and continue lines represents the shadow limits considering the estimated radius; when the shadow crosses the Earth's surface, the path is projected on the Earth;
- The blue dots are separated by a one-minute interval and the big blue dot corresponds to the nominal occultation time (which is the geocentric closest approach);
- The arrow shows the direction of the shadow motion;
- The 1-σ precision along the path is represented by the red dotted line;
- The G*, J* and RP* parameters are the G (from Gaia), J (from 2MASS) and the RP* (red photometer from Gaia DR2) magnitudes, normalized to a body moving at 20km/s in order to enhance very slow events (G* = G + 2.5 log (v/20) with v is the velocity in the skyplane (km/s)); Note that J was replaced by RP magnitude since Gaia DR2 publication;
- The body offset is at the upper right corner, if JPL ephemeris is used;
- Areas in dark grey correspond to full night (Sun elevation below -18 degrees) and areas in light grey correspond to twilight (Sun elevation between -18 and 0 degrees) while daytime is in white;
- Be careful, that the dates are in Universal Time, the night of the event may begin the day before.