K2 Cycle 6: Notable objects in Campaigns 17-18-19

News article posted on by Geert Barentsen

Proposals for targets to be observed by K2 in Campaigns 17, 18, and 19 are currently being solicited as part of K2 Guest Observer Cycle 6, with Phase 1 submissions due on October 12, 2017.

The fields of these campaigns will cover roughly 100 square degrees each towards the constellations of Virgo (C17), Cancer (C18), and Aquarius/Pisces (C19). To help inspire observing proposals, we offer below a list of notable targets that will be visible during these campaigns.

Campaign 17

Campaign 17 (Mar 1 - May 8, 2018) will observe a forward-facing field located towards the constellation of Virgo. The high galactic latitude of this field (+55°) makes it ideally suited to survey a large number of galaxies for the K2 Supernova Cosmology Experiment. The field also provides a substantial overlap with Campaign 6, offering a longer baseline for stellar activity, asteroseismology, and AGN studies, as well as enabling dozens of known K2 planet candidates to be revisited. The field also provides access to ~20 deg2 of previously unexplored sky.

Notable objects which may be proposed include:

  • Spica (V=1): the brightest star in the constellation of Virgo, known to be a rotating ellipsoidal variable with a period of four days.
  • EQ Virginis (V=9): a bright K-type flare star.
  • K2-41, K2-99, K2-110: stars hosting confirmed planets discovered during K2 Campaign 6.
  • RX J1347.5-1145: one of the most massive galaxy clusters known.


Campaign 18

Campaign 18 (May 12 - Aug 2, 2018) will observe a backward-facing campaign dedicated to revisit Campaign 5 and substantially overlap Campaign 16. The third visit to this key part of the sky that contains the M44 and M67 clusters will enable users to study benchmark targets with a 3-year baseline and 8-month duty cycle, enabling original Kepler-like science at a Galactic sightline that is located 130 degrees away from the original Kepler field in Cygnus. The field also provides access to more than one hundred previously-published K2 planets and planet candidates.

Notable objects which may be proposed include:

  • M67: the benchmark open cluster with solar-like age and metallicity.
  • M44 (aka Praesepe or the Beehive): a 600 Myr-old open cluster revealed by K2 Campaign 5 to contain several planets.
  • HIP 41378 (V=9): a bright F-type dwarf previously discovered by K2 to host at least 5 planets.
  • K2-34, K2-95, K2-97, K2-98, K2-100, K2-101, K2-102, K2-103, K2-104, K2-105, K2-108, K2-114, K2-115: additional stars hosting confirmed K2 planets.
  • OJ 287 (V=15): a well-studied galaxy thought to show lightcurve variations due to a binary supermassive black hole at its center.


Campaign 19

Campaign 19 (Aug 6 - Oct 10, 2018) will observe a forward-facing field near the constellation of Aquarius, partially overlapping Campaigns 3 and 12, while also providing access to ~15 deg2 of previously unstudied sky.

Notable objects which may be proposed include:

  • Neptune: the planet.
  • TRAPPIST-1 (V=19): the well-known M dwarf known to host 7 Earth-sized planets.
  • GJ 9827 (V=10): a K-type dwarf recently revealed to host at least three transiting planets near the rocky/gaseous divide.
  • HD 217107 (V=6): a bright G-type subgiant known to host two large RV planets.
  • Comet 2P/Encke (V=20): a well-known periodic comet.


Other candidate targets

In addition to the highlights listed above, Simbad lists a wealth of known objects that will be visible during these Campaigns. They include:

  • 28,857 Galaxies;
  • 1,979 known M dwarfs;
  • 799 High Proper-Motion stars;
  • 616 White Dwarfs;
  • 462 RR Lyr Variables;
  • 310 Active Galactic Nuclei;
  • 204 (candidate) Brown Dwarfs;
  • 44 Flare Stars;
  • 21 Cataclysmic Variables.

A full table containing all Simbad sources that are visible in C17-18-19 can be downloaded from this website in CSV format (K2-C17-C19-Simbad.csv) or as a VOTable (K2-C17-C19-Simbad.xml.gz). Beware however that Simbad is not a full catalog of all known sources; it merely lists objects that have previously been discussed in the literature. For the purpose of e.g. color-based target selections, we recommend using a more complete source catalog such as the EPIC.

As a reminder, the K2fov Python package enables you to test whether targets fall within a campaign field, while its sister K2ephem package allows moving Solar System bodies to be checked. Note that Campaigns 17-18-19 require K2fov version 7.0 or higher to be installed.