Securing the legacy of TESS through the care and maintenance of TESS planet ephemerides. (arXiv:1906.02197v1 [astro-ph.EP])
<a href="http://arxiv.org/find/astro-ph/1/au:+Dragomir_D/0/1/0/all/0/1">Diana Dragomir</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Harris_M/0/1/0/all/0/1">Mallory Harris</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Pepper_J/0/1/0/all/0/1">Joshua Pepper</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Barclay_T/0/1/0/all/0/1">Thomas Barclay</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Villanueva_S/0/1/0/all/0/1">Steven Villanueva Jr</a>
TESS has begun fulfilling its promise of delivering thousands of new
transiting planets orbiting nearby bright stars. The mission’s legacy will fuel
exoplanet science for many years to come, but much of this science relies on
precisely predicted transit times that are needed for many follow-up
characterization studies. We investigate the severity of ephemeris
deterioration for TESS planets, and find that most will have uncertainties
greater than 1 hour just one year after their TESS observations. It is the
mission’s relatively short observing baseline that drives this fast
deterioration. We identify the parameters that have the strongest impact on
this deterioration. We recommend that one or two follow-up transits be observed
three and/or nine months after the end of a planet’s TESS observations, in
order to refresh its ephemeris for two years past the follow-up observations.
We find that the longer the baseline between the TESS and the follow-up
observations, the longer the ephemerides will stay fresh, facilitating the
scheduling of future observations with expensive facilities such as the Hubble
Space Telescope, the James Webb Space Telescope, the ELTs, and Ariel.
TESS has begun fulfilling its promise of delivering thousands of new
transiting planets orbiting nearby bright stars. The mission’s legacy will fuel
exoplanet science for many years to come, but much of this science relies on
precisely predicted transit times that are needed for many follow-up
characterization studies. We investigate the severity of ephemeris
deterioration for TESS planets, and find that most will have uncertainties
greater than 1 hour just one year after their TESS observations. It is the
mission’s relatively short observing baseline that drives this fast
deterioration. We identify the parameters that have the strongest impact on
this deterioration. We recommend that one or two follow-up transits be observed
three and/or nine months after the end of a planet’s TESS observations, in
order to refresh its ephemeris for two years past the follow-up observations.
We find that the longer the baseline between the TESS and the follow-up
observations, the longer the ephemerides will stay fresh, facilitating the
scheduling of future observations with expensive facilities such as the Hubble
Space Telescope, the James Webb Space Telescope, the ELTs, and Ariel.
http://arxiv.org/icons/sfx.gif
