KIC 12557548 b is first of a growing class of intriguing disintegrating planet candidates , which lose mass in the form of \added a metal rich vapor that condenses into dust particles \deleted escaping their surface .
Here , we follow up two perplexing observations of the system : 1 ) the transits appeared shallower than average in 2013 and 2014 and 2 ) the parameters derived from a high resolution spectrum of the star differed from other results using photometry and low resolution spectroscopy .
We observe 5 transits of the system with the 61-inch Kuiper telescope in 2016 and show that they are consistent with photometry from the Kepler spacecraft in 2009-2013 \added , suggesting that the dusty tail has returned to normal length and mass .
We also evaluate high resolution archival spectra from the Subaru HDS spectrograph and find them to be consistent with a main-sequence T _ { \mathrm { eff } } =4440 \pm 70 K star in agreement with the photometry and low resolution spectroscopy .
This disfavors the hypothesis that planet disintegration affected the analysis of prior high resolution spectra of this star .
We apply Principal Component Analysis to the Kepler long cadence data to understand the modes of disintegration .
There is a tentative 491 day periodicity of the second principal component , which corresponds to possible long-term evolution of the dust grain sizes , though the mechanism on such long timescales remains unclear .