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tokens: panel) shows these “anomalous radial velocities” based on all three transit observations. Before making this plot, long-term trends in the PFS radial velocities were removed by subtracting the best-fitting quadratic function of time to the out-of-transit data. This trend need not be astrophysical; because the observations were obtained without the use of an iodine gas absorption cell, the radial velocities are susceptible to intra-night drift of the instrumental profile and wavelength solution. We computed a model for the anomalous radial velocity based on the system parameters in Table 1 , using code provided by Boué et al. ( 2013 ). The model agrees well with the data, even without any further tuning of the model parameters. With this way of displaying and analyzing the data, the effects of spots are not as obvious. This is because the spots migrate smoothly across a significant part of the stellar surface over the timescale of the transit. We note, though, that not accounting for the influence of spots can cause a systematic bias in the resulting derived obliquities from the Rossiter–McLaughlin effect. If one part of the star is dimmer due to the presence of a group of spots, then the overall weighted velocity variation induced by a planet will be affected by the specific part of the star the planet transits through. This bias is irrespective of any possible spot-crossing events. Systematic uncertainties arising from such issues will need to be accounted in the error budget in Rossiter–McLaughlin observations (e.g., Oshagh et al. 2018 ). A light curve motivated spot-modeling exercise, in conjunction with an Rossiter–McLaughlin observation, can encompass such systematic uncertainties (Montet et al. 2020 ). 4. Discussion The finding of a well-aligned star and planetary orbit would not have been surprising a decade ago. Since then, though, we have learned that stellar obliquities are sometimes very large (e.g., Winn et al. 2010a ; Albrecht et al. 2012 ), and no longer take spin–orbit alignment for granted. High-obliquity orbits have been interpreted as evidence for dynamical processes that tilt the orbit of a giant planet after its formation within the gaseous protoplanetary disk. The large majority of previous obliquity measurements have been made for close-in giant planets around mature-age stars (Figure 4 ). Figure 4. Age-obliquity distribution for planets with obliquity measurements. DS Tuc Ab is the youngest system with its orbital obliquity measured by nearly an order of magnitude. Other systems with ages are labeled. The vast majority of planetary systems have ages estimated from isochrone modeling. Note that Kepler-63 (labeled) has an age estimated from gyro-chronology and spectroscopic activity indicators (Sanchis-Ojeda et al. 2013 ). Kozai and secular dynamical interactions can form a portion of the close-in Neptune and Jovian population. Their representative timescales and resulting orbital obliquities are noted in the figure. DS