Comet C/2011 W3 (Lovejoy)

 

2011/12/04    2011/12/28    2012/02/01    2012/02/10    2012/02/24    2012/03/11    2012/03/22

 

2012 Mar 22

 
Optics Tokina 300mm f/2.8 lens
Camera Canon EOS 350D (ISO 1600)
Exposure 150 s x 23 frames
Processing images stacked in IRIS with calibration in MaxIm DL; further processed in Fitswork V4.42;
Comment Resolution is 9.03"/pixel, orientation around -4°.1. Mouse-over the image to browse labels.

 

 

4 Sequel colored version of the sequence stacked by means of arithmetical average.
Mouse-over the above image to browse the labels.

 

This session of observation failed to reveal any hint of the remnant of comet C/2011 W3, as the conditions resume to worsen. Another crucial reason why the observation was negative may well be that the faint nebulousity in the region yet severely cast influences on the identification. The following image presents these interstellar materials.

 

The uncropped image stacked with registration to stars in negative version, 0.5x.
Mouse-over the above image to browse the labels.
Click the image to see the version in 4-color sequels in full resolution.

Xing Gao, the director of Xingming Observatory has informed me that the observation of comet C/2011 W3 (Lovejoy) is hitherto put to an end attributed to the failure attempt. Conclusively, one has to admit that the observation made on Mar 11 is indeed our last success observation of its kind. For me by no means would it be a exhilarating denouement, but now all has to be over, sadly. However, when possible I will personally continue the quest by exerting myself until it goes beyond my limits. Attempt from Mt. Mulan due this weekend will absolutely become very tempting. Stay tune!

 

Copyright © Man-To Hui  2012/03/23


 

2012 Mar 11

 
Optics Tokina 300mm f/2.8 lens
Camera Canon EOS 350D (ISO 1600)
Exposure 120 s x 50 frames
Processing images arithmetically stacked in IRIS with calibration in MaxIm DL; further processed in Fitswork V4.42;
Comment Resolution is 9.03"/pixel, orientation around -4°.1. Mouse-over the image to browse labels.

 

 

The sequence stacked in median and converted in 4-color sequels.
Mouse-over the above image to browse the labels.

 

 

The uncropped image stacked with registration to stars in negative version, 0.5x.
Mouse-over the above image to browse the labels.
Click the image to see the version in 4-color sequels in full resolution.

The remnant of the comet proceeds to challenge our limitation, as proven in the stacked images. Although the remnant still persists, deteriorating conditions including lower altitude in the evening sky, therefore restricted observation spell, prevent us from obtaining a manifest image of it. To make matters worse, the remnant now is drown in a sky background teemed with faint and widespread nebulousity, which brings much more difficulty in identifying the remnant even when the stacked image is in pseudocolor, as seen in the last but one image. I strongly doubt that this session will likely be our last one of successful capture of comet C/2011 W3. Privately I do wish the day will never dawn.

 

Copyright © Man-To Hui  2012/03/18


 

2012 Feb 24

 
Optics Tokina 300mm f/2.8 lens
Camera Canon EOS 350D (ISO 800)
Exposure 60 s x 75 frames
Processing images stacked in IRIS with calibration in MaxIm DL; further processed in Fitswork V4.41;
Comment Resolution is 9.03"/pixel, orientation around -3°.6. Mouse-over the image to browse labels.

 

 

4 Sequel colored version of the same photograph above
Mouse-over the above image to browse the labels.

The remnant of the comet was significantly weaker than on Feb 10 during the last observation, therefore, I am afraid that it will finally come to dispersion in the following month before the moon contaminates the sky severely. I as well stacked the images with alignment to stars other than to the predicted motion of the comet in IRIS. Amazingly the comet stood out even clearer than in the image with registration to the comet. Yet I believe this is only an illusion cheated by human own vision. Had the star-subtraction method been preformed perfectly, I am confident that the result will be totally reverse.

 

Mouse-over the above image to browse the 4-color sequels version.

The uncropped image with registration to stars also rendered numerous DSOs.

 

Mouse-over the above image to browse the labels.
Click on the image to browse the image in full resolution.

 

 

Copyright © Man-To Hui  2012/02/25


 

2012 Feb 10

 
Optics Tokina 300mm f/2.8 lens
Camera Canon EOS 350D (ISO 1600)
Exposure 90 s x 35 frames
Processing 35 images stacked in IRIS with calibration in MaxIm DL; further processed in Fitswork V4.41;
Comment Mouse-over the image to browse a pseudocolored version.

 

 

4 Sequel colored version of the same photograph above

 

The observation was quite successful as the stacked image, frankly speaking, even some single frames, evidently show the remnant of the comet. So long as the field rotation was proved to be so obvious, I processed the images with alignment to the motion of the comet in IRIS. I am attempting to subtract the stars in each of the frames so as to make the structure of the remnant stand out more.

 

Copyright © Man-To Hui  2012/02/24


 

2012 Feb 01

 
Optics Tokina 300mm f/2.8 lens
Camera Canon EOS 350D (ISO 1600)
Exposure 90 s x 8 frames
Processing 8 images stacked in Astrometrica with calibration in MaxIm DL; further processed in Fitswork V4.41

 

 

Invertion of the same photograph above. Mouse-over to see labels noted.

 

 

Contour line of the original photograph. The comet appears in shadow.
Mouse-over to see labels noted.

 

 

4-color sequels of the original photograph. Mouse-over to see labels noted.

 

 

Corresponding star chart generated in GUIDE 8.0.

 

The observation was rather tough as the comet was only merely above the obstructions in the southern horizon of the Xingming Observatory. To make matters worse, the waxing gibbous moon lit the sky seriously. When the observation commenced, the star field was to be blocked by hills in the south. Initially when processing these images, I thought that the motion of the comet would not be so rapid and therefore I stacked the images with registeration to stars, which led to almost nothing but something extremely faint right in the direction of the comet's tail. The stacked image was shown to some of the staff in the Xingming Observatory, and the conclusion of hallucination was drawn by the majority of the people. Henceforth I was determined to reprocess the bundles of images with alignment to the motion of the comet, and now the evidence seems pretty obvious. Meanwhile, I am very pleased with the result that we managed to capture the comet under such poor conditions.

Frankly, another two-night observations of the comet were performed subsequently, but thus far I have not spotted any hint of the comet yet. More annoyingly, Astrometrica, the software I implement to stack the images with reference to comet's motion, malfunctioned in star-stacking. Despite much longer exposure, I do not hold much hope that the comet would be caught manifestly owing to the waxing moon. Yet anyway, the results may still be surprising.

 

Copyright © Man-To Hui  2012/02/04


 

2011 Dec 28

 
Time 2011-12-28 17:35:15 UT - 17:50:57 UT
Optics 0.18-m refractor f/7.1
Camera QSI 583ws CCD + Luminance filter
Exposure 30 s x 22 frames
Processing 22 images stacked in Astrometrica with calibration in MaxIm DL; further processed in Fitswork V4.42
Note Mouseover to browse the image in pseudocolored. For full resolution of the B/W version, click on the above image. For full resolution of the pseudoclored version, please click here. I have no idea how to measure such a diffuse and sizeable object in the images so no scientific work was done with images taken this day.

 

 

Copyright © Man-To Hui  2012/02/04


 

2011 Dec 04

 
For full information of the measurements please refer to the corresponding page in this page. Mouseover to see the version in pseudo color.

 

 

For full information of the measurements please refer to the corresponding page in this page. Mouseover to see the version in pseudo color.

 

 

Copyright © Man-To Hui  2012/02/04

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