Planet Hunters Talk

KOI Ponderer -- An interactive long-cadence light-curve viewer (Mac OSX)

  • rbnerfjr by rbnerfjr

    This note is to announce the availability of KOI Ponderer, a Mac OSX app for interactive viewing of long-cadence light-curves associated with Kepler Objects of Interest (KOIs). I was prompted to develop the app because I could not get a feel for the data using the PlanetHunter tools, and the NASA online diagnostic displays were overwhelming. I am a retired physicist, and my research “style” was to search for ways to display the data in a way that impedance-matched it to the strengths of the human visual system. I am also lazy, so I wanted a tool that could be relatively easily used.

    I won’t describe the app in detail here; the documentation mentioned below should suffice. However, an anecdote to show the goals were met: I demonstrated the app to an astronomer friend over microbrews, downloading Kepler data using the bar’s wifi. While ticking through various features of the app, we serendipitously discovered that the orbit for K00070.03 has a period 21 times that of K00070.02. This factoid may have no scientific value, but it does illustrate how a new tool can readily reveal unanticipated features in the data.

    I’m making the app available because it’s unlikely I will have the time to use it or further develop it during the next few months. I hope it can be useful as is. The app is available via two routes: The executable and documentation are in a DropBox folder, and the Xcode Project with source code is available on GitHub, for those who want to roll their own.

    The simplest way is to go to DropBox and download the zipped executable and the manual. For those who just want to window-shop, the pdf and the ibook provide an overview. For those without a Mac, the two mov files should be playable in Quicktime on Windows.
    will show a Dropbox folder containing five files: (404 kB) - which contains the app

    KOIpondererManual.pdf (4.8 MB) - which contains the basic documentation.

    KOIpondererMovies.ibooks (26 MB) - which contains two movies showing the app in action. (16 MB) - same as one in ibook, but doesn’t require Apple device to view. (56 MB) - same as one in ibook, but doesn’t require Apple device to view.

    Working with the download ibooks file is a bit confusing because the first movie comprises a chapter called Downloading. The second movie shows the new interaction paradigm.

    If you click on the zip file in Safari, it downloads and unzips itself. The app sets up its own KOI database, so there’s no installation necessary, beyond convincing OSX that you want to launch an unsigned app downloaded from the Internet. (You may have to control-click (rather than double-click) on it to convince the system that you’re serious about running it, and if not an “Admin” user, may require permission from one.)

    I have only tested it on OSX 10.9 (Mavericks), but it works on both my MacBook Retina from late 2013, and an iMac from mid 2010.

    For those who are geeky, masochistic and/or paranoid, the README file at GitHub will tell how to download the source files and build the app from scratch:

    I presume that eventually I’ll be able to figure out how to get the app itself onto GitHub, but until that happens I’ll keep the two separate ways.

    BTW, for the paranoid, here are the MD5 signatures for the DropBox files:

    MD5 ( = f93c5744f146e13643db42ad7bb73c2c

    MD5 ( = c57ae21fdc155a4a11b6706963508c68

    MD5 ( = 4b24112f731006d450997d6315de380d

    MD5 (KOIpondererManual.pdf) = cd258d85cb5d745853e66052a4d5ebb2

    MD5 (KOIpondererMovies.ibooks) = d4b49976e6bffb544ed004688e854c3e


  • troyw by troyw

    I don't have a mac, but can you post some screenshots? Glad to see another programmer on here!


  • rbnerfjr by rbnerfjr


    KOI 70.002&.003
    I'm unfamiliar with the posting technique here, so the preview shows a [?] image for the link I've included above.

    which should show a screenshot where the light curves are aligned so that 70.03 eclipses are centered and painted in green, and the 70.02 eclipses are painted in yellow. Since the yellow and green curves events are parallel, their periods have a harmonic relationship.

    The gray row in the table at upper left shows the star that is selected, and the table at lower right shows the eclipses for that star. The selected 70.03 eclipse set is selected in yellow.

    The KOIpondererManual.pdf on dropbox has more pics.

    If this doesn't work let me know, and I'll try something else...


  • troyw by troyw

    That is very cool. You've used a similar method as what I created for lightcurves.

    Here is the same data (detrended and different orientation) displayed in AKO (not the arrows). The green arrow is 70.03 and the blue arrows are 70.02.

    enter image description here


  • rbnerfjr by rbnerfjr

    I'll take a look at the AKO reference when I've got my focus back (Today I've been dealing with propagating the consequences of a multi-year IRA tax problem.). But your display certainly shows there is not an exact resonance between the two orbits.

    Your display reminds me of many examples I saw in the seismic data realm that illustrated a geophysical-velocity-model gone bad. I may share it with some not-yet-retired colleagues to remind them that their problems are universal:-)


  • DZM by DZM admin in response to rbnerfjr's comment.

    Today I've been dealing with propagating the consequences of a multi-year IRA tax problem.

    Sounds less fun than planet hunting. Hope it goes okay and you can return to us at some point! 😃


  • rbnerfjr by rbnerfjr

    OK, got a quick look at AKO, IMHO a great improvement over static displays. It showed to me how the choice of user interface and display technology have such a strong impact on what one can "grok" about the data. For one, AKO takes advantage of the human visual system's processing of spatial patterns to make details, that are subtle in KOI Ponderer, obvious.

    I had been unaware until today of the "sawtooth" noise in Kepler-2 data. It would be interesting to see how the two approaches deal with such artifacts... The human eye, and hand/eye coordination are amazing at ignoring the irrelevant (or being totally flummoxed thereby.)