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HabPlanet

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  1. It is important to note that at current stage we should treat this TCE as nothing more than just a candidate. First, the parameter space between 350 and 380 orbital days has the highest false alarm rate. All false alarms cluster at 370 days in Kepler data, so it naturally produces a peak of candidate planets and TCEs. Second, Kepler team's official automatic vetting system, Robovetter, did not detect this TCE in DR25 and previous DRs, although Robovetter also missed a lot of other TCEs. Third, in the inverted run, where light curve is inverted so any detected TCE has to be false alarm produced by noise, false alarms can be indistinguishable from true transit even to human eyes. They also cluster at 370 days. Fourth, only three transits are detected, but the chance of instrumental and stellar noise alignments three times are significantly greater than alignments of five times.
  2. I have the normalized pdcsap flux and time in google folder, if that's what you're looking for.
  3. There are a few possible transits at 466.7, 838.3, 842.0, 870.5, 900.6, 1195.6, and 1258.6
  4. Wow, just WOW! This is crazy. The 485.9 transit is shallower and shorter than others and the 1216.8 transit is deeper and longer than others, and they differ by a factor of 2. I wonder if this could be attributed to instrumental noise or two different planets transiting coincidently. Three transits have depths of ~84 ppm, ~129 ppm and ~177 ppm respectively, and the combined depth is ~116 ppm. Adopting your stellar radius would yield 1.19 (+0.31/-0.21) Re Adopting Berger et al (2018) would yield 1.15 (+0.37/-0.24) Re Considering the uncertainty, both overlap well. It would be funny if a galactic civilization created a mirror Earth and put it right at 100π pc (because Gaia DR2 parallax gives 313.172 (+2.296/-2.270) parsec for this star) as a sign of something for humans to discover....
  5. HST Confirmation of a Candidate Earth Analogue from the Kepler Primary Mission Investigators PI: Dr. Andrew Vanderburg University of Texas at Austin CoI: Dr. Laura Kreidberg Harvard University CoI: Chris Shallue Google AI CoI: David W Latham Smithsonian Institution Astrophysical Observatory Abstract http://www.stsci.edu/hst/phase2-public/15685.pdf http://www.stsci.edu/cgi-bin/get-proposal-info?id=15685&observatory=HST http://archive.stsci.edu/proposal_search.php?mission=hst&id=15685 The reported visit target in the proposal is 2MASS-J19432996+5059289. In the Kepler target catalog, this star is called KIC 12266812. HST has completed the observation two weeks ago and the analysis is underway. Gaia DR2 parallax gives a distance of 1010~1030 light years and stellar radius (0.978 Rs) and effective temperature (5908 K) literally identical to our Sun. The three transits and periods detected by Kepler seem identifiable and robust to my eyes. Based on HST's visit time and period reported in the proposal, the transits must have taken place during 485-487, 851-852, and 1216-1217 (BJD-2,454,833). The light curves below are obtained from Time Series Viewer. This is my own analysis on KIC 12266812, yielding a transit depth at around ~120 ppm and duration around 10 hours. https://drive.google.com/drive/u/0/folders/1pG8fzxWzAJ0MU3NMSA7T55Mbh2BurIIL If confirmed, this planet will be the most similar planet to Earth, literally an Earth twin with identical size, orbital period, orbital distance, insolation, host star, and maybe even biosphere, although the result from HST observation takes about three years to publish.
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