Comments

The TTV plot for this amateur data appears to be plagued by systematic errors, which is a more credible interpretation than the one requiring another planet in a resonant orbit. An investigation by Alonso et al (link) of precision measurements of 80 consecutive transits (139 days) by CoRoT showed no evidence for TTV greater than ~10 seconds. This result was obtained by analyzing LC data in a way that minimized stellar activity effects; when the data were processed using a simple LC fitting procedure the greatest TTV anomaly was ~20 seconds. Therefore it is unlikely that the TTV of this amateur data is real, but it does illustrate one of the things we're looking for.

Basic data - updated 2009.08.22

    RA = 19:27:06.5, DE = +01:23:02
    Season = July 14
    V = 12.57
    HJDo = 4706.4041 ± 0.0030 & P = 1.7429964 ± 0.0000017 days (as listed at Extrasolar Planets Encyclopaedia)
    HJDo = 4706.40111 (35) & P = 1.7429949 (9) days (AXA fit)
    Depth = 35.2 ± 0.3 mmag
    Length = 2.26 ± 0.02 hr
    Fp = 0.33 ± 0.05, F2 = 0.82 ± 0.08

Amateur observations - updated 2009.08.22

Light Curves - Amateur

Light curves in this small section have not been included in the table & plost in above sections



9903LCO


Light curve plots below here have been included in the table & plots in above sections



9828SG21


8723OJ2

Light curves below here have been included in above table & plots



9723WPK


9716WPK  Note: This is B-band data.

Light curves below here have been included in updates to table & plots (above)



9814NR2


9712AC21


9627LC2


Normally I don't accept observations with a span of less than 2 hours but this one spanned a predicted egress and the depth is large and with well-established length and shape it's possible to objectively constrain all parameters but mid-transit time and extract something useful. To judge whether the result is useful I note that its contribution to the TTV plot is eminently believable.


8824fcn1



8819roe1


8813mqz1


8806nra1


8804roe1







8729roe3


8729roe2


8606ayiC


8606KSM  Same data as below but auto-fit result.



8607klid


Light Curves - Professional


Copied from discovery paper: Alonso et al, 2008

8922oye1

Finder Charts

References

Discovery paper: Alonso et al, 2008a
TTV & Secondary Transit Search: Alonso et al, 2008b

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WebMaster: Bruce L. Gary.  Nothing on this web page is copyrighted. This site opened:  May 08, 2008.  Last Update:  2009.11.06