Exoplanet Candidates
Overview
The exoplanet candidate stars are likely hosts for exoplanets. These are stars plucked from NASA’s Kepler and TESS space telescopes. They are not designed to look photo-realistic but, rather, are diagrammatic in nature and demonstrate the sheer number of candidate stars that continue to be examined for planets. The nature of these stars is not as important as their abundance and distribution in the solar neighborhood.
Note
These candidate stars are colored by their mission:
Yellow: the Kepler mission
Orange: the K2 mission
Green: the TESS mission stars
This data set demonstrates the scientific process in action. Stars here are, in a sense, temporary, as they are discovered, then confirmed to be a host to planets, or discounted as a host. The data shrink over time while being replenished with new observations that require follow-up observations to make a confirmation one way or the other.
Note
See this section’s top page page for some background on exoplanets.
Kepler Mission
The Kepler mission was designed to stare at one spot, roughly twelve degrees across, in the constellation Cygnus. By staring at one spot, the spacecraft could monitor over 500,000 stars in that field for subtle variations in brightness.
These slight differences in brightness signify the transit of the star’s planet, so we must view the planetary orbit edge-on for Kepler to detect a planet. In order to be considered a candidate for exoplanets, the observations must pass several tests to rule out other factors that could affect the brightness.
The exoplanet candidate stars looking toward the constellations Cygnus and Hercules. Yellow stars are from the Kepler mission while green stars are from TESS. The 12-degree Kepler field used to be defined to the extent that one could see the footprint of the telescope’s detector. However, many of the former candidate stars have been either ruled a host to planets (and moved into the Exoplanets), or were ruled out as planetary hosts. Thus, the detector footprint is not as well defined anymore, but is better defined in the Exoplanets data now.
The K2 Mission
In July 2012, Kepler lost control of four of its reaction wheels that provide attitude control of the spacecraft. And, less than one year later, one of the two remaining reaction wheels failed, threatening the entire mission. In response to this, the K2 mission was proposed as an extension of the original mission. The spacecraft was limited to searching along the ecliptic, the plane containing Earth’s orbit around the Sun (or the annual path of the Sun in the sky). This is roughly the plane of the solar system, which is tipped about 62 degrees to the Milky Way Galaxy.
The exoplanet candidate stars looking toward the constellations Virgo, Leo, and Cancer. The orange stars are from the K2 mission and the green stars are from TESS.
TESS Mission
The Kepler telescope was shut down in late 2018 after its fuel was expended; however, TESS was launched that same year and is now detecting planets. Kepler, with its narrow patch of sky coverage, was a case study, if you will. TESS will observe a much larger swath of sky and will detect a far greater number of planets.
While Kepler gave us a taste of the number of exoplanets out there, TESS will fulfill that potential by seeing far more sky and filling in those areas of the galaxy where we’ve not ever looked for planets.
As seen from afar, the exoplanet candidate stars are huddled around the Sun. Green stars are from TESS, yellow stars extend to the left of the Sun in this image and are from Kepler, and orange stars, from Kepler’s K2 mission, extend in all directions along the ecliptic, though they look like a flat disk here, they more resemble a pinwheel from a different vantage point.
Profiles
Dossier
Census: |
8,589 stars |
|---|---|
Asset File: |
|
OpenSpace Version: |
2 |
Reference: |
|
Prepared by: |
Brian Abbott, Zack Reeves, Emily Rice, Jason No (AMNH) |
Source Version: |
12.09 |
License: |