Planet Hunters Talk

Skyview with EPIC numbers?

  • Ptd by Ptd

    I'd like to learn how to look/check for contamination, I am presuming this is done by finding out what the EPIC numbers for nearby Kepler Targets are and looking at their LCs hoping to find a culprit?

    I can pull up a Skyview image, based on what I found on the Kepler site I used the DSS2 red, but I can't work out how to lay a catalog of EPIC numbers over it, I tried the link I found on the Kepler site but it seemed not to work when I pasted it into the Skyview query form.

    I've tried searching this forum and I've consulted the mighty Google and can't find a How To beyond what is here which I think might be out of date? That or I'm somehow doing it wrong

    Can anyone help or am I going about this the wrong way?

    Some pointers would be appreciated



  • ajamyajax by ajamyajax

    There are several 'easy' ways to look for contamination that I can think of.

    SkyView works, but you must enter the K2 search text:

    for Overlays/Catalog Overlays/Vizier Catalog or Catalog URL. Then save the data of course to view each record. And last I checked, the Firefox browser worked for this on a Windows PC, but Internet Explorer did not.

    Also you can enter your target on the NEA search near "Explore the Archive" with a radius of objects to include in that search. And an EPIC prefix is required, e.g. 'EPIC 210940839' and then add a radius of 100-200 arcsecs.

    You will get a page that includes a list of 2MASS and EPIC sources if any are found and their distance away in arc-seconds. And then you can look up the 2MASS objects in star catalogs (see elsewhere for how to do that, or just search the internet) and you can view each EPIC light curve as you did this one and look for related features and transit periods.

    Another method is VSX which can give you a nice listing of nearby sources:

    It also shows how close they are, often what they are, and a period if one is on record. But you need an RA/Dec for that search. Thankfully those are available on the K2 search you are already are using:

    And to use VSX, press the "More" button at the bottom of the page and enter the RA/Dec coordinates in the Position box. You can also change the radius of the search here in the size box just below that. (Edit: and you probably already know about VSX, just mentioning it for others.)

    Hope this helps. Good luck.