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tokens: September 20, this was an 1833 (spatial) by 15 (slit width) box, 2019 October 1 had 15575 by 10, 2019 October 9 had 260 by 15, and 2019 October 10 had 18′′ by 24. The imaging data were extracted using circular aperture photometry with a radius of 250 and largely followed the reduction procedure outlined in Farnham et al. ( 2000 ) using the dust reflectance slope measured from our 2019 October 10 spectrum. The standard star used (HD 81809) is noted in that work to be less than ideal for blue/UV observations, so we have overestimated errors when possible. We note that for the 2019 September 20 and October 1 data sets, insufficient data were collected to allow a median combination of spectra, making the two data sets “look” even noisier than their later counterparts even though cosmic rays were cleaned from them. 3. Analysis, Modeling, and Results In order to search for molecular emission features, it is necessary to produce a flux-calibrated solar spectrum fit to subtract from the flux-calibrated data. This process creates a dust reflectance spectrum for the comet, which can be used to look for a spectral slope. The solar spectrum was taken from Chance Kurucz ( 2010 ) and binned to the resolution of each data set. The original flux-calibrated spectra, best-fit reflectance, and dust-subtracted comet spectra are shown in Figure 1 . The noisiness of the Bok data prevents a high-quality solar reflectance subtraction, while the later data become very linear after subtraction indicating a relatively good fit of the solar spectrum to the continuum points. Figure 1. Spectral observations of 2I/Borisov. The flux-calibrated and dust-subtracted spectra of all three nights of spectroscopy from 2019 October. The heliocentric and geocentric distances are listed underneath the telescope names and dates on the figure. The same background and background-subtraction process was applied to all data sets. The CN B–X (0–0) band centered at 388.3 nm can be seen clearly in the MMT and LBT data. (The data used to create this figure are available .) We consider the spectral slope between the blue, green, and red continuum regions defined for the Hale–Bopp filter set (Farnham et al. 2000 ) to compare reflectance slopes with other workers. These filters are centered at 4450, 5260, and 7128 Å, respectively. If we normalize our highest-quality data from 2019 October 10 at the green continuum point, then we find the blue-to-green slope to be S ′ = 22+/−4%/micron, and the green-to-red slope to be S ′ = 11+/−3%/micron. Fitzsimmons et al. ( 2019 ) suggested that the dust might be “redder” at shorter wavelengths, and our best data support that conclusion. After the reflected sunlight from dust was subtracted, we searched for emission from molecules in the coma of 2I/Borisov (Table 2 ). For each possible feature we subtracted a linear estimate of the background as determined by a fit to data on either side of the feature and then integrated using a trapezoidal method all flux