Asteroid 285263 (1998 QE2) Photometry: Individual Light Curves
Webmaster: Bruce L. Gary.  Latest update: 2013.07.27, 00.5 UT

Each observing session (date) consists of several FOV placements. Each FOV set of images is processed independently of the others. Therefore, there will be a LC for each FOV placement. This web page is organized with the latest observing date at the top, and within an observing date section LCs are arranged with time increasing downward. The first graph for each date is the combined LC for all LC segments that follow. Beneath each LC segment graph is a link to the data upon which the graph is based. The header for that data gives the FOV image center, number of reference stars used, number of stars with APASS magnitudes used for setting the magnitude scale,  RMS of plot of APASS minus measured magnitudes versus color (using a fitted slope of zero), etc. You may disregard the sinusoidal fits to FOV data segments (these are used merely to determine RMS scatter of the data with respect to a simple model).

Observing Sessions (Total = 64.8 hours, 15 consecutive nights plus 3)

    2013.06.21 6.2 hours (1 segment  ), processed using MFE; primary expected at 4.0 UT but I don't see it (data noisy)
    2013.06.14 8.4 hours (2 segments), processed using MFE
    2013.06.09 7.3 hours (4 segments), processed using MFE; primary event present at 10.3 UT
    2013.06.07 7.9 hours (6 segments), processed using MFE
    2013.06.06 2.0 hours (2 segments), processed using MFE; secondary event present at 4.3 UT.
    2013.06.05 3.8 hours (4 segments), processed using MFE; no events expected
    2013.06.04 4.5 hours (6 segments), processed using MFE; primary expected at 5.1 UT but I don't see it.
    2013.06.03 4.1 hours (6 segments), processed using MFE
    2013.06.02 4.2 hours (5 segments), processed; a secondary event is predicted at 6.1 UT (but data ends at 6.2 UT)
    2013.06.01 4.0 hours (5 segments), not yet processed
    2013.05.31 6.0 hours (7 segments), processed; a primary event is present at 7.2 UT
    2013.05.30 2.5 hours (3 segments), processed
    2013.05.29 4.6 hours (3 segments), not yet processed; a secondary event is expected at 8.2 UT
    2013.05.28 4.0 hours (5 segments), not yet processed
    2013.05.27 3.0 hours (5 segments), not yet processed
    2013.05.26 2.3 hours (2 segments), not yet processed
    2013.05.25 2.8 hours (3 segments), not yet processed
    2013.05.24 1.8 hours (1 segment  ), not yet processed

Offset Stack of Observing Session LCs, Phase-Folded


Note that when an observing session is longer than a rotation period different symbols are used where there's phase overlap.

Individual Light Curves

2013.06.21 (6.2 hrs, 1 segment)


Data for entire observing sessionThe two vertical lines are separated by 4.7546 hours (Petr's periodicity of LC variations). Ephemeris-predicted magnitude change during observing session has been compensated for.


   data   Data gaps correspond to passage near background star.


   data   Even though only 1 FOV placement was used for the night the asteroid's movement was not in a straight line for a the entirety of the observing session, so I'm treating the night's data in two parts.  Data gaps correspond to passage near background star.


2013.06.14 (8.4 hours, 2 segments, processed)


Data for entire observing sessionThe two vertical lines are separated by 4.7546 hours (Petr's periodicity of LC variations).


   data  


   data  

2013.06.09 (7.3 hours, 4 segments, processed)


Phase folded version of this observing session showing possible eclipse, or transit, of the secondary.


Data for Entire Observing Session Note the two vertical lines, separated by 4.765 hours. No magnitude adjustments have been applied to the FOV data segments. I spent ~10 days processing this observing session's data in the most conscientious way I could devise (using a MFE, or mosaic-based flattening equation, for flat field calibration), so I "believe in it." See phase-folded plot (above) for explanation of a difference in shape and level of the last FOV segment compared with the first one.


   data  


   data  


   data  


   data  

2013.06.07 (7.9 hrs, 6 segments, all 6 processed)


Data for Entire Observing Session MFE processed data. Note the two vertical lines, separated by 4.764 hours. No magnitude adjustments have been applied to the FOV data segments. A fading trend is evident (even though each FOV segment has been adjusted for ephemeris-predicted magnitude).


Same data as above but phase folded.


   data   MFE processed.


   data   MFE processed.


   data   MFE processed.


   data   MFE processed.


   data   MFE processed.


   data   MFE processed.

2013.06.06  (2.0 hrs, 2 segments, process complete)


  Data for entire obs'g sessionCombining FOV segments (w/o mag adjustments). Both segments processed using MFE. A secondary event is predicted for 4.0 UT, and it appears to be present at 4.3 UT in this LC.


   data  


   data  


2013.06.05 (3.8 hrs, 4 segments, 4 done)



Data for Entire Observing Session (not updated yet). Combining FOV segments (w/o mag adjustments). All data reprocessed using MFE.


   data   Re-processed using MFE procedure. The first 10 minutes were made before sky was dark & are therefore suspect.


   data  


   data  


   data  

2013.06.04 (4.5 hrs, 6 segments, 3 done using MFE)



   Data for entire observing session   No FOV segment magnitude adjustments yet. All segments have been processed using the MFE procedure. A primary transit is predicted for 5.1 UT.


   data  


   data  


   data  


   data  


   data   Uses MFE (HighSpatialFreq flat).


   data  


2013.06.03


 
Data for Segments using MFE No FOV segment adjustments. All data processed using MFE.


  
data   Reprocessed using MFE.


   data  
Reprocessed using MFE.


   data  
Reprocessed using MFE.


   data  
Reprocessed using MFE.


   data  
Reprocessed using MFE.


   data  


2013.06.02


5 FOV segments, all processed


Data for Entire Observing Session Combining of FOV segments without magnitude adjustments. A secondary event is predicted for 6.1 UT.


    data 


   data 


   data  


   data  


   data  

2013.06.01

5 FOV segments, not yet processed.

2013.05.31



Data for Entire Observing Session  A primary event is predicted for 7.2 UT, and indeed there is a "dip" at 7.4 UT.


  
data  


data


   data


   data  


   data  


   data  


   data  

2013.05.30


Data for Entire Observing Session


   data 


   data  


   data    


2013.05.29


3 FOV segments, not yet processed

A secondary event is predicted for 8.2 UT.


2013.05.28


5 FOV segments, not yet processed

2013.05.27

5 FOV segments, not yet processed

2013.05.26

2 FOV segments, not yet processed

A primary event is predicted for 2.0 UT.


2013.05.25

3 FOV segments, not yet processed

2013.05.24

1 FOV segment, not yet processed

A secondary event is predicted for 3.0 UT.


Related Links
    Hardware & Analysis Procedures
    Results (home)


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WebMaster: Bruce L. GaryNothing on this web page is copyrighted. This site opened:  2013 May 29