IOTA/IOTA-ES occultation update for (32532) Thereus / UCAC4 428-050687 event on 2021 Mar 19, 22:16 UT Visible from Europe, Africa Summary ------- On 2021 Mar 19 UT, the 86.5 km diameter asteroid (32532) Thereus will occult a 14.3 mag star in the constellation Hydra for observers along a path across Europe, Africa. In the case of an occultation, the combined light of the asteroid and the star will drop by 5.84 mag to 20.12 mag (the magnitude of the asteroid) for at most 4.6 seconds. This update is based on, astrometry for the asteroid kindly provided by the IAU Minor Planet Center. This work has made use of data from the European Space Agency (ESA) mission Gaia (http://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, http://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. The event at a glimpse ---------------------- * Rank: 26 * date and approx. time of event: 2021 Mar 19, 22:09 - 2021 Mar 19, 22:18 * geocentric midpoint of event [JD]: 2459293.42643750 * magnitude of target star: 14.29 * magnitude drop [mag]: 5.84 * estimated maximum duration [s]: 4.6 * Moon: 33 % sunlit, 76° distance * Sun: 142° distance * rough path description: Europe, Africa The occultation path -------------------- * approximate projected width [km]: 115 * 1 sigma uncertainty interval [path widths]: +/- 2.61 * 1 sigma uncertainty interval [seconds]: +/- 15.0 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- 0.037, +/- 0.023) * 1 sigma uncertainty ellipse (major, minor, PA): (0.037", 0.023", 99°) * approx speed of asteroid's shadow [km/s]: 18.6824 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of UCAC4 428-050687 by 32532 Thereus on 2021 Mar 19 Centre Star Star Sun Path Limits Error Limits Alt E. Longitude Latitude U.T. Alt Az Alt Limit 1 Limit 2 Limit 3 Limit 4 Crn o ' " o ' " h m s o o o o ' " o ' " o ' " o ' " Longitude Longitude Longitude Longitude .. .. .. 82 0 0 .. .. .... .. .. .. ... .. .. ... .. .. - 54 58 18 ... .. .. .... .. .. .. 81 0 0 .. .. .... .. .. .. ... .. .. ... .. .. - 48 38 44 ... .. .. .... .. .. .. 80 0 0 .. .. .... .. .. .. - 67 37 34 ... .. .. - 43 45 40 ... .. .. .... - 64 28 56 79 0 0 22 18 19.5 2 126 0 - 59 53 26 - 69 32 2 - 39 48 20 ... .. .. .... - 57 49 49 78 0 0 22 18 18.9 4 133 -1 - 54 1 30 - 61 52 35 - 36 29 37 ... .. .. -0.64 Latitude Latitude Latitude Latitude - 57 0 0 77 51 19 22 18 18.8 4 133 -1 78 32 14 77 10 57 82 15 53 .. .. .. -0.82 - 56 0 0 77 40 28 22 18 18.6 4 134 -2 78 21 50 76 59 39 82 8 14 .. .. .. -0.82 - 55 0 0 77 29 10 22 18 18.5 4 135 -2 78 11 0 76 47 54 82 0 14 .. .. .. -0.83 - 54 0 0 77 17 24 22 18 18.3 5 136 -2 77 59 43 76 35 41 81 51 52 .. .. .. -0.83 - 53 0 0 77 5 8 22 18 18.1 5 137 -2 77 47 57 76 22 57 81 43 7 .. .. .. -0.83 - 52 0 0 76 52 23 22 18 17.9 5 138 -3 77 35 42 76 9 43 81 33 58 .. .. .. -0.83 - 51 0 0 76 39 6 22 18 17.6 6 139 -3 77 22 56 75 55 56 81 24 23 .. .. .. -0.84 - 50 0 0 76 25 16 22 18 17.4 6 140 -3 77 9 38 75 41 36 81 14 21 .. .. .. -0.84 - 49 0 0 76 10 52 22 18 17.1 6 141 -3 76 55 46 75 26 40 81 3 50 .. .. .. -0.84 - 48 0 0 75 55 51 22 18 16.8 7 142 -4 76 41 19 75 11 9 80 52 50 .. .. .. -0.84 - 47 0 0 75 40 14 22 18 16.4 7 143 -4 76 26 16 74 54 59 80 41 19 .. .. .. -0.84 - 46 0 0 75 23 57 22 18 16.1 7 144 -4 76 10 34 74 38 10 80 29 14 70 50 30 -0.85 - 45 0 0 75 7 0 22 18 15.7 8 145 -5 75 54 12 74 20 39 80 16 33 70 30 30 -0.85 - 44 0 0 74 49 21 22 18 15.2 8 146 -5 75 37 8 74 2 26 80 3 16 70 9 46 -0.85 - 43 0 0 74 30 58 22 18 14.8 9 147 -5 75 19 21 73 43 29 79 49 20 69 48 16 -0.85 - 42 0 0 74 11 48 22 18 14.3 9 148 -6 75 0 48 73 23 45 79 34 42 69 25 59 -0.85 - 41 0 0 73 51 51 22 18 13.7 9 149 -6 74 41 28 73 3 13 79 19 21 69 2 54 -0.85 - 40 0 0 73 31 4 22 18 13.1 10 150 -6 74 21 18 72 41 51 79 3 14 68 38 58 -0.85 - 39 0 0 73 9 26 22 18 12.5 10 151 -7 74 0 17 72 19 38 78 46 18 68 14 10 -0.86 - 38 0 0 72 46 54 22 18 11.8 11 152 -7 73 38 22 71 56 31 78 28 30 67 48 29 -0.86 - 37 0 0 72 23 26 22 18 11.1 11 153 -8 73 15 32 71 32 28 78 9 49 67 21 54 -0.86 - 36 0 0 71 59 1 22 18 10.3 12 154 -8 72 51 44 71 7 28 77 50 11 66 54 22 -0.86 - 35 0 0 71 33 36 22 18 9.4 12 155 -9 72 26 56 70 41 29 77 29 33 66 25 53 -0.86 - 34 0 0 71 7 9 22 18 8.5 13 156 -9 72 1 6 70 14 28 77 7 52 65 56 25 -0.86 - 33 0 0 70 39 39 22 18 7.5 13 157 -10 71 34 12 69 46 24 76 45 4 65 25 57 -0.86 - 32 0 0 70 11 3 22 18 6.4 14 158 -10 71 6 11 69 17 15 76 21 7 64 54 28 -0.86 - 31 0 0 69 41 19 22 18 5.2 14 159 -11 70 37 1 68 46 59 75 55 58 64 21 57 -0.86 - 30 0 0 69 10 26 22 18 4.0 15 160 -11 70 6 41 68 15 35 75 29 32 63 48 22 -0.86 - 29 0 0 68 38 21 22 18 2.6 16 161 -12 69 35 9 67 43 1 75 1 46 63 13 42 -0.87 - 28 0 0 68 5 4 22 18 1.1 16 162 -12 69 2 23 67 9 15 74 32 38 62 37 58 -0.87 - 27 0 0 67 30 33 22 17 59.6 17 163 -13 68 28 21 66 34 17 74 2 4 62 1 8 -0.87 - 26 0 0 66 54 46 22 17 57.9 18 164 -14 67 53 1 65 58 5 73 30 2 61 23 11 -0.87 - 25 0 0 66 17 43 22 17 56.1 18 165 -14 67 16 23 65 20 39 72 56 27 60 44 9 -0.87 - 24 0 0 65 39 23 22 17 54.2 19 166 -15 66 38 26 64 41 58 72 21 19 60 3 59 -0.87 - 23 0 0 64 59 44 22 17 52.1 20 166 -16 65 59 8 64 2 0 71 44 34 59 22 44 -0.87 - 22 0 0 64 18 48 22 17 49.9 21 167 -17 65 18 30 63 20 47 71 6 11 58 40 23 -0.87 - 21 0 0 63 36 33 22 17 47.5 21 168 -17 64 36 31 62 38 19 70 26 7 57 56 56 -0.87 - 20 0 0 62 53 1 22 17 45.0 22 169 -18 63 53 11 61 54 35 69 44 24 57 12 25 -0.87 - 19 0 0 62 8 11 22 17 42.4 23 171 -19 63 8 32 61 9 36 69 0 59 56 26 50 -0.87 - 18 0 0 61 22 6 22 17 39.5 24 172 -20 62 22 33 60 23 24 68 15 53 55 40 13 -0.87 - 17 0 0 60 34 45 22 17 36.5 25 173 -21 61 35 16 59 36 0 67 29 6 54 52 36 -0.87 - 16 0 0 59 46 12 22 17 33.3 26 174 -22 60 46 44 58 47 26 66 40 41 54 3 59 -0.87 - 15 0 0 58 56 27 22 17 29.9 26 175 -23 59 56 57 57 57 44 65 50 39 53 14 26 -0.87 - 14 0 0 58 5 34 22 17 26.4 27 176 -24 59 5 58 57 6 55 64 59 2 52 23 59 -0.88 - 13 0 0 57 13 35 22 17 22.6 28 177 -25 58 13 50 56 15 4 64 5 55 51 32 40 -0.88 - 12 0 0 56 20 32 22 17 18.7 29 178 -26 57 20 37 55 22 12 63 11 19 50 40 31 -0.88 - 11 0 0 55 26 31 22 17 14.5 30 179 -27 56 26 21 54 28 23 62 15 21 49 47 36 -0.88 - 10 0 0 54 31 33 22 17 10.2 31 180 -28 55 31 7 53 33 41 61 18 5 48 53 58 -0.88 - 9 0 0 53 35 43 22 17 5.7 32 181 -29 54 34 57 52 38 8 60 19 35 47 59 40 -0.88 - 8 0 0 52 39 5 22 17 1.0 33 182 -30 53 37 57 51 41 50 59 19 59 47 4 45 -0.88 - 7 0 0 51 41 42 22 16 56.0 34 184 -31 52 40 11 50 44 50 58 19 20 46 9 16 -0.88 - 6 0 0 50 43 41 22 16 50.9 35 185 -32 51 41 44 49 47 12 57 17 46 45 13 19 -0.88 - 5 0 0 49 45 4 22 16 45.6 36 186 -33 50 42 39 48 49 1 56 15 22 44 16 55 -0.88 - 4 0 0 48 45 56 22 16 40.2 37 187 -34 49 43 2 47 50 20 55 12 15 43 20 9 -0.88 - 3 0 0 47 46 22 22 16 34.5 37 189 -36 48 42 57 46 51 15 54 8 32 42 23 4 -0.88 - 2 0 0 46 46 26 22 16 28.7 38 190 -37 47 42 29 45 51 49 53 4 17 41 25 44 -0.88 - 1 0 0 45 46 14 22 16 22.7 39 192 -38 46 41 43 44 52 7 51 59 39 40 28 14 -0.88 0 0 0 44 45 49 22 16 16.6 40 193 -39 45 40 44 43 52 14 50 54 41 39 30 36 -0.88 1 0 0 43 45 15 22 16 10.3 41 194 -40 44 39 35 42 52 13 49 49 32 38 32 54 -0.88 2 0 0 42 44 38 22 16 3.8 42 196 -42 43 38 22 41 52 9 48 44 15 37 35 12 -0.88 3 0 0 41 44 1 22 15 57.2 42 197 -43 42 37 10 40 52 5 47 38 57 36 37 33 -0.88 4 0 0 40 43 29 22 15 50.6 43 199 -44 41 36 1 39 52 7 46 33 43 35 40 1 -0.88 5 0 0 39 43 5 22 15 43.7 44 201 -45 40 35 0 38 52 17 45 28 37 34 42 40 -0.88 6 0 0 38 42 53 22 15 36.8 44 202 -47 39 34 12 37 52 39 44 23 45 33 45 31 -0.88 7 0 0 37 42 57 22 15 29.8 45 204 -48 38 33 39 36 53 17 43 19 10 32 48 39 -0.88 8 0 0 36 43 20 22 15 22.7 46 206 -49 37 33 26 35 54 15 42 14 58 31 52 6 -0.88 9 0 0 35 44 6 22 15 15.6 46 207 -50 36 33 36 34 55 35 41 11 11 30 55 55 -0.88 10 0 0 34 45 18 22 15 8.4 47 209 -52 35 34 12 33 57 20 40 7 54 30 0 9 -0.88 11 0 0 33 46 58 22 15 1.1 47 211 -53 34 35 17 32 59 34 39 5 10 29 4 51 -0.88 12 0 0 32 49 10 22 14 53.8 47 213 -54 33 36 54 32 2 18 38 3 2 28 10 3 -0.88 13 0 0 31 51 55 22 14 46.4 48 215 -55 32 39 5 31 5 37 37 1 33 27 15 46 -0.88 14 0 0 30 55 18 22 14 39.0 48 217 -57 31 41 53 30 9 31 36 0 46 26 22 4 -0.88 15 0 0 29 59 19 22 14 31.6 48 218 -58 30 45 21 29 14 4 35 0 43 25 28 59 -0.88 16 0 0 29 4 0 22 14 24.2 48 220 -59 29 49 30 28 19 16 34 1 26 24 36 32 -0.88 17 0 0 28 9 25 22 14 16.8 49 222 -60 28 54 23 27 25 12 33 2 58 23 44 45 -0.88 18 0 0 27 15 34 22 14 9.5 49 224 -61 28 0 1 26 31 51 32 5 20 22 53 40 -0.88 19 0 0 26 22 30 22 14 2.1 49 226 -62 27 6 25 25 39 15 31 8 35 22 3 18 -0.88 20 0 0 25 30 13 22 13 54.8 49 228 -63 26 13 39 24 47 27 30 12 43 21 13 40 -0.88 21 0 0 24 38 46 22 13 47.5 49 230 -65 25 21 42 23 56 28 29 17 46 20 24 49 -0.88 22 0 0 23 48 9 22 13 40.3 48 231 -66 24 30 36 23 6 18 28 23 45 19 36 45 -0.88 23 0 0 22 58 23 22 13 33.1 48 233 -67 23 40 23 22 16 59 27 30 41 18 49 29 -0.88 24 0 0 22 9 30 22 13 25.9 48 235 -68 22 51 3 21 28 33 26 38 36 18 3 2 -0.88 25 0 0 21 21 31 22 13 18.9 48 236 -69 22 2 37 20 40 58 25 47 30 17 17 26 -0.88 26 0 0 20 34 26 22 13 11.9 47 238 -70 21 15 6 19 54 18 24 57 23 16 32 40 -0.88 27 0 0 19 48 16 22 13 4.9 47 239 -70 20 28 31 19 8 32 24 8 18 15 48 46 -0.88 28 0 0 19 3 1 22 12 58.1 47 241 -71 19 42 52 18 23 41 23 20 13 15 5 44 -0.88 29 0 0 18 18 43 22 12 51.3 46 242 -72 18 58 10 17 39 46 22 33 9 14 23 35 -0.88 30 0 0 17 35 22 22 12 44.7 46 244 -73 18 14 26 16 56 46 21 47 8 13 42 19 -0.88 31 0 0 16 52 57 22 12 38.1 45 245 -73 17 31 39 16 14 43 21 2 9 13 1 57 -0.88 32 0 0 16 11 30 22 12 31.6 44 246 -74 16 49 50 15 33 37 20 18 12 12 22 28 -0.88 33 0 0 15 31 0 22 12 25.3 44 248 -74 16 9 0 14 53 28 19 35 18 11 43 55 -0.88 34 0 0 14 51 29 22 12 19.0 43 249 -75 15 29 8 14 14 16 18 53 26 11 6 15 -0.88 35 0 0 14 12 55 22 12 12.8 43 250 -75 14 50 14 13 36 1 18 12 37 10 29 30 -0.88 36 0 0 13 35 20 22 12 6.8 42 251 -75 14 12 20 12 58 44 17 32 50 9 53 41 -0.88 37 0 0 12 58 42 22 12 0.9 41 252 -75 13 35 24 12 22 24 16 54 7 9 18 46 -0.88 38 0 0 12 23 3 22 11 55.1 40 253 -75 12 59 27 11 47 3 16 16 26 8 44 46 -0.88 39 0 0 11 48 22 22 11 49.4 40 254 -75 12 24 29 11 12 38 15 39 47 8 11 41 -0.88 40 0 0 11 14 40 22 11 43.8 39 255 -74 11 50 30 10 39 12 15 4 11 7 39 31 -0.88 41 0 0 10 41 55 22 11 38.3 38 255 -74 11 17 29 10 6 42 14 29 37 7 8 16 -0.88 42 0 0 10 10 8 22 11 33.0 37 256 -74 10 45 27 9 35 11 13 56 5 6 37 56 -0.88 43 0 0 9 39 19 22 11 27.8 37 257 -73 10 14 23 9 4 36 13 23 35 6 8 31 -0.88 44 0 0 9 9 28 22 11 22.7 36 258 -73 9 44 17 8 34 59 12 52 6 5 40 1 -0.88 45 0 0 8 40 34 22 11 17.8 35 258 -72 9 15 9 8 6 19 12 21 39 5 12 25 -0.88 46 0 0 8 12 38 22 11 13.0 34 259 -71 8 47 0 7 38 35 11 52 12 4 45 44 -0.88 47 0 0 7 45 39 22 11 8.3 33 259 -71 8 19 48 7 11 48 11 23 47 4 19 56 -0.88 48 0 0 7 19 36 22 11 3.7 32 260 -70 7 53 33 6 45 58 10 56 22 3 55 4 -0.88 49 0 0 6 54 31 22 10 59.3 31 260 -69 7 28 16 6 21 4 10 29 57 3 31 5 -0.88 50 0 0 6 30 22 22 10 55.0 30 261 -68 7 3 56 5 57 6 10 4 32 3 7 59 -0.88 51 0 0 6 7 9 22 10 50.8 30 261 -67 6 40 32 5 34 4 9 40 7 2 45 48 -0.88 52 0 0 5 44 53 22 10 46.8 29 262 -67 6 18 6 5 11 57 9 16 42 2 24 30 -0.88 53 0 0 5 23 32 22 10 42.9 28 262 -66 5 56 35 4 50 46 8 54 16 2 4 5 -0.88 54 0 0 5 3 7 22 10 39.1 27 262 -65 5 36 1 4 30 30 8 32 48 1 44 33 -0.89 55 0 0 4 43 37 22 10 35.5 26 263 -64 5 16 22 4 11 9 8 12 19 1 25 54 -0.89 56 0 0 4 25 3 22 10 32.0 25 263 -63 4 57 40 3 52 43 7 52 49 1 8 7 -0.89 57 0 0 4 7 24 22 10 28.6 24 263 -62 4 39 53 3 35 12 7 34 16 0 51 13 -0.89 58 0 0 3 50 40 22 10 25.4 23 263 -61 4 23 1 3 18 35 7 16 42 0 35 12 -0.89 59 0 0 3 34 50 22 10 22.3 22 264 -60 4 7 4 3 2 52 7 0 5 0 20 2 -0.89 60 0 0 3 19 55 22 10 19.3 21 264 -59 3 52 2 2 48 3 6 44 26 0 5 45 -0.89 61 0 0 3 5 54 22 10 16.5 20 264 -58 3 37 55 2 34 8 6 29 44 - 0 7 41 -0.89 62 0 0 2 52 47 22 10 13.8 19 264 -57 3 24 43 2 21 7 6 15 59 - 0 20 15 -0.89 63 0 0 2 40 34 22 10 11.2 18 264 -56 3 12 25 2 9 0 6 3 11 - 0 31 57 -0.90 64 0 0 2 29 16 22 10 8.7 17 264 -55 3 1 1 1 57 46 5 51 20 - 0 42 48 -0.90 65 0 0 2 18 50 22 10 6.4 16 265 -54 2 50 31 1 47 25 5 40 25 - 0 52 48 -0.90 66 0 0 2 9 19 22 10 4.3 15 265 -53 2 40 56 1 37 57 5 30 27 - 1 1 56 -0.90 67 0 0 2 0 41 22 10 2.2 14 265 -52 2 32 14 1 29 23 5 21 26 - 1 10 13 -0.90 68 0 0 1 52 57 22 10 0.3 13 265 -51 2 24 27 1 21 42 5 13 20 - 1 17 39 -0.91 69 0 0 1 46 6 22 9 58.5 12 265 -50 2 17 33 1 14 53 5 6 11 - 1 24 14 -0.91 70 0 0 1 40 8 22 9 56.9 11 265 -49 2 11 33 1 8 58 4 59 58 - 1 29 59 -0.91 71 0 0 1 35 4 22 9 55.4 11 265 -48 2 6 27 1 3 55 4 54 40 .. .. .. -0.92 72 0 0 1 30 53 22 9 54.0 10 265 -47 2 2 14 0 59 46 4 50 20 .. .. .. -0.92 73 0 0 1 27 35 22 9 52.8 9 265 -46 1 58 56 0 56 29 4 46 55 .. .. .. -0.93 74 0 0 1 25 11 22 9 51.7 8 265 -45 1 56 31 0 54 6 4 44 26 .. .. .. -0.93 75 0 0 1 23 40 22 9 50.7 7 265 -44 1 54 59 0 52 35 4 42 53 .. .. .. -0.94 76 0 0 1 23 2 22 9 49.9 6 265 -43 1 54 22 0 51 57 4 42 17 .. .. .. -0.95 77 0 0 1 23 18 22 9 49.2 5 265 -42 1 54 39 0 52 13 4 42 37 .. .. .. -0.97 78 0 0 1 24 28 22 9 48.6 4 265 -41 1 55 49 0 53 22 4 43 54 .. .. .. -1.00 79 0 0 1 26 31 22 9 48.2 3 265 -40 1 57 54 0 55 24 4 46 7 .. .. .. -1.04 80 0 0 1 29 29 22 9 47.9 2 265 -39 2 0 53 0 58 19 4 49 16 .. .. .. -1.14 81 0 0 1 33 20 22 9 47.7 1 265 -38 2 4 47 1 2 8 4 53 23 .. .. .. -1.58 Uncertainty in time = +/- 16 secs Prediction of 2021 Jan 31.0 Data for the target star ------------------------ * name: UCAC4 428-050687 * constellation : Hydra * BCRS position with proper motion to date of event [h,m,s ; °,',"] RA: 09 26 15.7163 DE: -04 29 03.481 * GCRS Astrometric position with proper motion and parallax to date of event [h,m,s ; °,',"] RA: 09 26 15.7163 DE: -04 29 03.481 * position source: Gaia EDR3 * standard error: RA,DE [mas]: (0.100,0.100) * V mag [mag]: 14.3 * Diameter [mas]: 0.00 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (32532) Thereus asteroid class: Centaur approx. diameter [km]: 87 approx. diameter ["]: 0.010 distance from Earth [AU]: 11.40240 asteroid position offset in RA [mas]: 0 asteroid position offset in DE [mas]: 0 * orbital information: orbit source: JPL#47 date of fit: 2020 Nov 13 source of used astrometry: MPC, JPL number of used observations: 0 number of rejected observations: 0 time covered by the observations: 1800 Jan 01 - 1800 Jan 01 1 sigma uncertainty ellipse (major, minor, PA): 0.037", 0.023", 99.1° remarks: * orbital elements for (32532)Thereus : Mean anomaly = 228.93285265 deg Arg. of pericenter = 87.08598598 deg Long. of node = 205.21014858 deg Inclination = 20.36892011 deg Eccentricity = 0.20056421 Semimajor axis = 10.60594865 AU Perihelion dist = 8.47877495 AU Mag: H = 9.10, G = 0.15 Epoch of elements : MJD 59292.92826389 TDT (2021 Mar 19.9283) ------ occelmnt file for Occult BEGIN ----------------------------------- JPL#472020Nov13,4.6,2021,3,19,22.2345,0.42074,0.50724,-8.12124,6.72604,0.00374,0.00039,0.00000,0.00000 -9.3590,-4.5775,-151.62,-0.19,False UCAC4 428-050687,9.43769898,-4.4843002,0.00,14.29,0.00,0.0,0,,9.45543555,-4.5775440 32532,Thereus,20.12,86.5,11.4024,0,0,-0.419,5.18,,8.8 0,228.9064,2021,3,19,87.0860,205.2101,20.3689,0.20056,10.60595,8.47877,9.10,5.0,0.15 3.610,0.0370,0.0230,99,0.0273,Known errors 20210319_050687,59245.00 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2021 Jan 31, 18:12 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 stevepr@acm.org