This deposit includes the synthetic NICER data sets along with the necessary auxiliary files used in the cross-verification efforts of the parameter estimation procedures used by Miller et al. (2019) and Riley et al. (2019) to analyze the NICER data of the millisecond pulsar PSR J0030+0451. The parameters assumed in generating the synthetic data are are detailed in the ApJ Letter listed above. Three sets of files are provided corresponding to the following comparison exercises described in the ApJ Letter: 1. Ultra-compact neutron stars with R/M~3 (see Section 2.3 of Letter) -- the tar.gz file and it's MD5 checksum are: multiple_imaging_validation.tar.gz (dd7a02b2ccf0a45da4e9d3a779d3b9c4) 2. A neutron star with a single, uniform-temperature, circular hot spot (see Section 3.1 of Letter) -- the tar.gz file and it's MD5 checksum are: one_spot_synthetic_NICER_data.tar.gz (87b9ca80259b34d76746ef18802a75ec) 3. A neutron star with two different, Uniform-Temperature, circular hot spots (see Section 3.2 of Letter) -- the tar.gz file and it's MD5 checksum are: two_spot_synthetic_NICER_data.tar.gz (75374adc0cea2bc1039f6169548cc719) A readme file contained within each tarball provides detailed information about the file sets used and the parameter values assumed in generating the synthetic data sets.