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2009-11-08 XO-2b Exoplanet Transit >
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XO-2b Transit Opportunities – Nov 2009 Excel graph showing calculated transit opportunities during November 2009 Opportunity on Nov 8th (highlighted) coincided with an evening of very good weather conditions |
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XO-2b Transit Opportunity – 2009-11-08 Excel graph showing calculated airmass for the transit opportunity on Nov 8th Airmass during the opportunity is not ideal, being greater than 1.5 throughout. Conditions at Ingress (airmass 2.5) were expected to be particularly challenging |
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XO-2 – Earlier Image from May 2007 XO-2 (GSC 3413:0005) shown |
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Annotated CCD Image 3 x 60s (average combine), 2x2 binning, C Filter 2007-05-07 22:56 hUT (#196028-30) |
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| XO-2 Reference Stars – Earlier Image from May 2007 | ||||||||||||||||||||
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| Annotated CCD Image 30s, 2x2 binning, R Filter 2007-05-07 23:07 hUT (#196040) |
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XO-2 with comparison/check stars ,
2009-11-08 Single 15s V frame (captured in CCDsoft, displayed in AIS/Image Viewer) |
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'StarGraph' showing star data for above 15s V frame Data confirms good signal/noise ratios, no pixel saturation FWHM values at 21 deg altitude (3.6") are reasonable to good for my site |
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XO-2b Transit, 2009-11-08 - Time Series Data Real time graphs showing instrumental magnitudes, ambient temperature, sky brightness and FWHM across the transit window Conditions were good good for entire run, atmosphere pretty steady except for a slightly anomalies at around mid-transit and just after Egress. Temperature falling by 2.25 degC across the run Improving instrumental magnitudes and FWHM values through the run reflect the impact of decreasing airmass. Scope was auto-guided between frames to keep the comparison and variable star on approximately the same pixel positions Focusing was auto-compensated for temperature changes |
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XO-2b Transit, 2009-11-08 - Calculated Magnitudes Time Series graphs showing calculated magnitude of XO-2 and the control star Calculated magnitudes are determined using the differential magnitudes between respective star and the Comparison Star Calculated data looks reasonably flat and indicate that the instrumental magnitude fluctuations have been appropriately correctly. Data scatter is noted to reduce through the run as the airmass decreases. Average Magnitude of XO-2 for entire period is 11.22 (V), compared to expected XO-2 magnitude of 11.18 (V) |
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XO-2b Transit, 2009-11-08 - Normalised
Differential Magnitudes Time Series graphs showing differential magnitudes (normalised based on average pre-ingress values) Data scatter is rather high at start of run due to airmass (2.5) but improves as airmass decrease through the run> Control star data appears flat throughout the run, whereas the XO-2 data takes a slight, but noticeable dip during the predicted transit window. |
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XO-2b Transit, 2009-11-08 - Detail Time Series graphs showing normalised differential magnitudes in detail Blue dots at datavalues associated with individual frames whilst yellow dots are a moving average Whilst data scatter (+/-0.032m to +/-0.018m) is larger than the expected transit depth (0.015 mag), and there the control star data is not totally flat, the overall dip in XO-2 brightness through the transit window is still noticeable. |
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| XO-2 with comparison/check stars, 2009-11-08 |
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Annotated CCD Image (full frame) 25 x 15 sec exposure (average combine), 3x3 binning, V Filter 2009-11-08 18:53 h UT (#397043-67) 12" LX200R (at f/5.7) + ST-10XME |
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| This Web Page: | Notes - Session 397 (2009-11-08) |
| Last Updated : | 2015-05-16 |
| Site Owner : | David Richards |
| Home Page : | David's Astronomy Web Site |
