made accurate and detailed atmospheric measurements. These include measuring the ozone layer, haze (aerosol optical depth), and the total column water vapor. The project began in May 1988, when Mims started experimenting with making UV-B measurements using homemade equipment. In 1989, Mims designed and built the first Total Ozone Portable Spectrometer (TOPS) to monitor ozone, and instruments to measure haze and water vapor. The first TOPS (Total Ozone Portable Spectrometer) ozone instrument earned a 1993 Rolex Award. On February 4, 1990, these instruments were first used at solar noon to measure the ozone layer, haze (aerosol optical depth) and total column water vapor. The photograph at left by Mims wife Minnie was made February 4, 2016, the 26th anniversary date. The various sun photometers, radiometers and cameras on the table are used every day at solar noon when the sun is not blocked by clouds. See Wikimedia and www.forrestmims.org for 25-year charts of total ozone, total water vapor and optical depth (haze). Mims' original LED sun photometer (placed in service during fall 1989) is in his left hand. Two Microtops II are in his right hand. One is among the first (1997) and the other is the only MicroTOPS II with LED’s as photodetectors. Mims first LED sun photometer is still in use (he is shown holding it in the 26th anniversary photo above). It has dual LED’s acting as narrow band sensors, one at 830 nm and another at 940 nm (near-IR). The 830 nm LED is for optical depth. The ratio of the photocurrents from the 830 nm and 940 nm LEDs provides total water vapor. The chart at right shows the total ozone measured from 1990 through 2016. Total ozone (Dobson units) measured at solar noon at Geronimo Creek Observatory since February 4, 1990. Measurements conducted only when sun is open and free of clouds. Mims has compared his measurements against Dobson 76 and Brewers 009 and 119 at the Mauna Loa Observatory each year since 1992. In addition to measuring total ozone, Mims has measured the aerosol optical depth (AOD) at 830 nm with his original instrument since 1990. The chart at left shows the data. Measurements made at or near solar noon when the sun is not obstructed by clouds. Peaks indicate smoke, dust and smog. Saharan dust events are measured each summer. The chart at right shows the total column water vapor measured since