Moon conditions - W5LUU Distance from the earth to the moon and cosmic noise from the direction of the moon are predictable variables that substantially affect the EME (moonbounce) communication path. Data on the 144 and 432 Mhz signal to noise degradation (DGRD) due to these factors and other relevant EME data for 1999 are attached. The data is for Sundays at 0000 UT to provide a guide to the expected weekend conditions. During 1999 the RA for perigee is moving into a more favorable alignment with northern delination and cold sky. Conditions will improve as the year progresses. Two weekends are rated excellent -DGRD below 1.0 dB. The variation in earth-moon distance over a monthly lunar cycle can introduce a change of over 2.4 dB in the path loss with the minimum being at perigee. Since sky noise varies with moon position the RA at which perigee occurs is very important in determining EME conditions. Best conditions occur when perigee is near RA of 9 + 1 to 2 hours. However, the RA for moon perigee is a cyclical function with a period of about 9 years. For 1992 and 1993 perigee occured near the cold sky region and 144 MHz DGRD was frequently under 1.0 dB. During 1994 conditions started to deteriorate as perigee occurred in an increasingly noisy part of the sky. Conditions will be excellent again (DGRD<0.5 dB) for many days in 2000-2002. The maximum monthly declination will also increase to 20+ this year. MOONDATA includes: DEC.(deg.) - Moon declination in degrees north and south (-) of the equator. This is cyclical with an average period of 27.212221 days. The maximum declination is also cyclic with a range of +18.15 to +28.72 and a period of about 19 years. Next maximum is in September 2006. RA (Hrs). - Right ascension (in hours). East-west position of the moon against sky background. RA cycle has average period of 27.321662 days but can vary from the average by a day or two. 144 MHz Temp. (K) - 144 MHz sky (cosmic) noise in direction of the moon expressed as temperature. Range Factor (dB) - The additional EME path loss, in dB, due to the earth-to-moon separation distance being greater than the absolute minimum (348,030 km surface-to-surface) reference. Varies from a low (0 to 0.7 dB) at perigee to as much as 2.43 dB at apogee. DGRD, dB - Shows for both 144 MHz and 432 MHz the degradation in EME signal-to-noise, in dB due to the excess sky noise (assuming a very narrow beam antenna) plus the earth-moon separation distance for the moon position at that time and date. During a monthly lunar cycle this factor can vary more than 13 dB at 144 and 8 dB at 432. DGRD is referenced to lowest possible sky noise along the moonpath, system noise temperatures of 80 K at 144 and 60 K at 432 and the absolute minimum perigee distance. 144 and 432 DGRD are equally affected by EME distance but at 432 the sky noise varies over a smaller range. Moon Phase - Shows new moon (NM) and full moon (FM) along with number of days (d) before (-) or after (+), or the time of occurrence of, these events. At NM sun noise is a problem while at FM the stable night time conditions can be advantageous. Conditions - Summary of EME conditions as controlled by DGRD at 144 MHz and new moon. Conditions may be worse due to ionospheric disturbance but not better than indicated. In general 144 MHz DGRD under 1.0 is considered excellent, 1.0 to 1.5 is very good, 1.5 to 2.5 is good, 2.5 to 4.0 is moderate, 4.0 to 5.5 is poor and over 5.5 is very poor. New moon can make otherwise good conditions very poor. W5LUU WEEKEND MOONDATA - 1999 FOR SUNDAYS AT 0000 UT DATE DEC RA 144 MHz RANGE DGRD, dB MOON CONDX 1999 Deg. Hrs TEMP FACTOR 144 432 PHASE K dB MHz MHz JANUARY 03 18.9 7.7 273 0.73 2.3 1.1 FM + 1d GOOD 10 -4.9 13.6 326 2.21 4.4 2.7 POOR 17 -19.3 19.3 698 1.66 6.7 3.5 NM 1546 NG 24 4.7 1.5 298 0.75 2.6 1.2 MODERATE 31 17.9 8.3 204 0.97 1.6 1.1 FM 1606 GOOD FEBRUARY 07 -7.3 14.1 353 2.20 4.7 2.7 POOR 14 -18.6 19.9 429 1.48 4.6 2.4 NM -2d POOR 21 8.1 2.2 338 0.62 2.9 1.2 MODERATE 28 16.4 8.9 170 1.26 1.3 1.2 FM -2d VY GOOD MARCH 07 -9.7 14.6 388 2.23 5.0 2.9 POOR 14 -17.6 20.4 345 1.39 3.8 2.0 MODERATE 21 11.2 2.9 364 0.39 3.0 1.0 NM +3d MOD. 28 14.4 9.6 183 1.49 1.8 1.5 FM -3d GOOD APRIL 04 -12.2 15.1 425 2.29 5.4 3.1 POOR 11 -16.4 21.0 331 1.40 3.6 1.9 MODERATE 18 13.7 3.5 357 0.16 2.7 0.8 NM +2d MOD. 25 12.1 10.2 193 1.61 2.1 1.7 GOOD MAY 02 -14.5 15.7 476 2.34 5.9 3.3 FM +2d VY PR 09 -14.8 21.6 339 1.45 3.8 2.0 MODERATE 16 15.8 4.1 370 0.06 2.7 0.7 NM +.5d PR-NM 23 9.5 10.9 206 1.62 2.3 1.7 GOOD 30 -16.5 16.3 613 2.34 6.8 3.5 FM 0640 VY PR JUNE 06 -12.6 22.2 265 1.48 3.0 1.8 MODERATE 13 17.5 4.6 424 0.10 3.2 1.0 NM 1803 POOR 20 6.9 11.4 232 1.59 2.6 1.7 MODERATE 27 -18.0 16.9 826 2.28 8.0 3.8 FM -2d VY POOR JULY 04 -9.9 22.9 244 1.41 2.6 1.7 MODERATE 11 18.8 5.2 493 0.29 4.0 1.4 NM -2d MOD. 18 4.3 12.0 259 1.56 3.0 1.9 MODERATE 25 -19.1 17.5 1840 2.20 11.1 5.3 FM -3d VY POOR AUGUST 01 -6.7 23.5 244 1.24 2.4 1.6 GOOD 08 19.7 5.9 500 0.53 4.3 1.8 NM -3d POOR 15 1.6 12.5 310 1.60 3.6 2.1 MODERATE 22 -19.9 18.0 3129 2.14 13.3 6.7 VERY POOR 29 1.4 1.0 283 0.87 2.6 1.3 FM +2d MOD SEPTEMBER 05 20.2 6.7 398 0.74 3.6 1.6 MODERATE 12 -1.3 13.0 313 1.72 3.8 2.3 NM +2d MOD 19 -20.3 18.6 1775 2.11 10.9 6.0 VERY POOR 26 -0.2 0.7 275 0.70 2.3 1.1 FM +.5d GOOD OCTOBER 03 20.1 7.4 313 0.85 2.9 1.3 MODERATE 10 -4.2 13.5 322 1.90 4.0 2.3 NM +.5d POOR 17 -20.4 19.2 779 2.14 7.6 4.3 VERY POOR 24 2.8 1.2 289 0.49 2.3 0.9 FM 2102 GOOD 31 19.3 8.2 208 0.83 1.5 1.0 VERY GOOD NOVEMBER 07 -7.2 14.0 351 2.07 4.5 2.6 NM -1d POOR 14 -20.2 19.45 487 2.18 5.8 3.3 VERY POOR 21 5.5 1.7 308 0.43 2.4 0.9 FM -2d GOOD 28 18.0 8.9 172 0.71 0.8 0.7 *EXCELLENT DECEMBER 05 -10.1 14.6 392 2.19 5.0 2.9 NM -3d POOR 12 -19.3 20.4 349 2.17 4.6 2.8 POOR 19 8.1 2.3 340 0.54 2.9 1.1 MODERATE 26 16.4 9.5 181 0.57 0.8 0.5 FM +3d EXCELNT JANUARY 2000 02 12.3 15.2 433 2.23 5.4 3.0