\theta  Cygni is an F3 spectral-type main-sequence star with visual magnitude V=4.48 .
This star was the brightest star observed by the original Kepler spacecraft mission .
Short-cadence ( 58.8 s ) photometric data using a custom aperture were obtained during Quarter 6 ( June-September 2010 ) and subsequently in Quarters 8 and 12-17 .
We present analyses of the solar-like oscillations based on Q6 and Q8 data , identifying angular degree l = 0 , 1 , and 2 oscillations in the range 1000-2700 \mu Hz , with a large frequency separation of 83.9 \pm 0.4 \mu Hz , and frequency with maximum amplitude \nu _ { max } = 1829 \pm 54 \mu Hz .
We also present analyses of new ground-based spectroscopic observations , which , when combined with angular diameter measurements from interferometry and Hipparcos parallax , give T _ { \mathrm { eff } } = 6697 \pm 78 K , radius 1.49 \pm 0.03 R _ { \odot } , [ Fe/H ] = -0.02 \pm 0.06 dex , log g = 4.23 \pm 0.03 .
We calculate stellar models matching the constraints using several methods , including using the Yale Rotating Evolution Code and the Asteroseismic Modeling Portal .
The best-fit models have masses 1.35–1.39 M _ { \odot } and ages 1.0–1.6 Gyr . \theta  Cyg ’ s T _ { \mathrm { eff } } and log g place it cooler than the red edge of the \gamma Doradus instability region established from pre- Kepler ground-based observations , but just at the red edge derived from pulsation modeling .
The best-fitting models have envelope convection-zone base temperature of \sim 320,000 to 395,000 K. The pulsation models show \gamma Dor gravity-mode pulsations driven by the convective-blocking mechanism , with periods of 0.3 to 1 day ( frequencies 11 to 33 \mu Hz ) .
However , gravity modes were not detected in the Kepler data ; one signal at 1.776 c d ^ { -1 } ( 20.56 \mu Hz ) may be attributable to a faint , possibly background , binary .
Asteroseismic studies of \theta  Cyg , in conjunction with those for other A-F stars observed by Kepler and CoRoT , will help to improve stellar model physics to sort out the confusing relationship between \delta Sct and \gamma Dor pulsations and their hybrids , and to test pulsation driving mechanisms .