2015-05-06 5h13 to 5h27
(107) Camilla
Occulted star mag 11.9 V

Overview

             The 6th may 2015, the double system (107) Camilla will occult a 11.9 V
      magnitude Tycho star. The event will be observable from USA and SW Canada.

             The satellite S/2001 (107) 1 was discovered in 2001 using the Hubble
      Space Telescope by A. Storrs et al.

              For this event we have collected 39 observations of this satellite, between 2001 to 2011.
      All images were taken with Hubble Space Telescope and with adaptative optic
      system from Very Large Telescope and Keck Observatory. These observations 
      span 3906 days or 1052 revolutions. The mean accuracy of the orbital solution 
      is 9 mas. 
            
              With a velocity of 13.7 km/s for the shadow, and an estimated diameter 
      of 16 km for the satellite, the estimated maximum duration of the event 
      is ~1.2 seconds. To ensure an accurate observation of the occultation 
      by the satellite, we recommend to use an integration time of 0.2 second or less.

          Clear skies

Prediction for (107) Camilla

Download the Google Earth File KMZ

Legend :

Explanation about color line and the errors limits :

We are using genetic algorithm to fit an orbit on observations. In our case, the method consist to minimize a performance function. We use for that, Chi2 minimization taking into account error on measurements. During the step of minimization, the all orbits are selected following regions, as 1, 2 or 3 (and more) sigma region. In the aim to give an idea of the error bars on orbit's parameters.

The color lines on the prediction path are derived from these orbits. All of them are projected to the date of occultation. We take the farthest orbit for each region along the shadow path to determine color lines. It's not derived from ellipse error like as show for the primary path, and it's not perfectly fully representative because limited by time computation for the benefit to obtain a solution quickly. That's why it's not centered on the best solution for the satellite (in white color). But in comparison, for the last occultation by Kleopatra, the one-sigma region for CleoSelene included the full orbit of the satellite.

Here, for Camilla, the uncertainty region in the tangent plane, has a larger of 121 km for 1-sigma, 135 km for 2-sigma, and 152 km for 3 sigma. Projected on earth using Occult software by D. Herald, we measure with google-earth : 132 km for 1-sigma, 143 km for 2-sigma, and 166 km for 3 sigma. It's important to note, that the sigma region represented here, don't take into account the accuracy of the primary Camilla occulting the Tycho star. If you want to make an idea of the realistic error bar, add the one-sigma distance from the path of Camilla, on each side of one-sigma error of the satellite.


Projection of best individuals from Genetic Algorithm for the 6th may 2015, date of the occultation
Green, blue and red represent respectively the 1,2 and 3 sigma regions.
Big Dot show the farthest orbit along the shadow path for each sigma regions.

Prediction for (107) Camilla and S/2001 (107) 1 (wide views)

Ephemeris

Ephemeris for (107) Camilla

Ephemeris for S/2001 (107) 1

Ephemeris from Miriade for the date of occultation and geocenter frame. For more specific ephemeris please use the documentation of Miriade.

Geometry of orbit for the (107) Camilla system view from Earth

Orbitography for the (107) Camilla system


Observations in adaptative optics centered on (107) Camilla.
Dot represents one observed position. The vector shows ephemeris position from observed position.

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