Full-Disk Wideband Photometry of the Moon: R and I filter Measurements

A total of 42 full-disk brightness measurements of our Moon are reported. These measurements include the entire lunar disk including the Earthlit portion. All measurements were made on the Johnson R (red) and I (infrared) system and were fitted to cubic equations. The results are summarized in this report. The selected normalized magnitudes of the Moon are R(1,0) = -0.70 ± 0.10 and I(1,0) = -1.12 ± 0.06. The selected geometric albedo is 0.18 ± 0.01 for the Johnson R and I system

Jupiter\u27s Changing North Equatorial Belt

New monthly latitude measurements of the northern and southern boundaries of Jupiter’s North Equatorial Belt (NEB) are reported for 1995 to 2011. The latitudinal width oscillated with a period of about 4½ years during this time. This is similar to the behavior between 1896 and 1953 as reported in the literature. One new finding is that the width changed over a few months. The barge, a dark and almost rectangular-shaped spot, is the most well observed feature in the NEB. It was decided to investigate what affect the changing NEB had on the number and drift rate of barges. There is little correlation between belt width and the number of NEB barges. There is also little correlation between belt width and the average drift rate of NEB barges

Wideband Photometry of Saturn in 2004-2005

The writer made 60 photometric measurements of Saturn + rings between Nov. 5, 2004 and Jan. 21, 2005. The normalized magnitudes of Saturn for a ring tilt angle of 22° are B(1,0) = -8.55 ± 0.01, V(1,0) = -9.60 ± 0.01, B(1,0) = -10.27 ± 0.01, and I(1,0) = -10. 4 7 ± 0.01; the corresponding solar phase angle coefficients are cB = 0.027 ± 0.006, cV = 0.021 ± 0.005, cB = 0.020 ± 0.005, and cB = 0.022 ± 0.005. The 2005 opposition surge values (in magnitudes at a = 0°) are B = 0.24 ± 0.05, V = 0.18 ± 0.05, R = 0.16 ± 0.05, and I = 0.27 ± 0.05

Photoelectric Magnitude Measurements of the Lunar Eclipses on May 16, 2003 and Oct. 28, 2004

The Moon\u27s brightness dropped by 10.73 ± 0.07 and 10.61 ± 0.15 magnitudes during the total lunar eclipses on May 16, 2003 and Oct. 28, 2004 respectively. These magnitude drops are close to the corresponding value for the Jan., 2000 total lunar eclipse and indi­cate that not much change in the transparency of the atmosphere has occurred in the last 4 years

The January 21, 2019 Lunar Eclipse

The B- and V-filter brightness values of the eclipsed Moon on January 21, 2019 were measured. The brightness values near mid-eclipse are B = –0.33 (0.15) and V = –2.07 (0.05) magnitudes. Uncertainties are in parentheses. The V-filter brightness near mid-eclipse compares well with a recent lunar eclipse model by Mallama; however, the measured B – V value [1.74 (0.16) magnitudes] is below the predicted value of

Wideband Photometry of Saturn in 2006-2007

The writer carried out brightness measurements of Saturn and its rings with four different color filters. The selected normalized mag­nitudes of Saturn + rings for a ring tilt angle of 14° are B(1,0) = -8.25 ± 0.03, V(1,0) = -9.36 ± 0.03, R(1,0) = -10.01 ± 0.04 and 1(1,0) -10.16 ± 0.04. The opposition surge values for Saturn+ rings on Feb. 11, 2007 (solar phase angle = 0.15°) were 0.19 and 0.06 magnitudes for the Band V filters respectively. The writer concludes that the B-V and V-R color indexes of Saturn+ rings do not change much when the solar phase angle drops from 6° to 1°. The rings become a little bluer though as the solar phase angle drops from 1° to 0° due to the larger opposition surge in blue light

Variability of Mars\u27 Seasonal North Polar Cap

Mars’ seasonal north polar cap (hereafter sNPC) underwent year-to-year changes between 2008 and 2015 or Mars years 29–33. The writer monitored changes in the sNPC using images made with the MARCI camera onboard the Mars Reconnaissance Orbiter (MRO). Nine isolated bright spots corresponding to Korolev, Lomonosov, and Louth Craters, the albedo features Ierne, Olympia (or Lemuria), and Cecropia, and three unnamed features were examined. The following was concluded: 1) the sNPC underwent small year-to-year changes between 2008 and 2015 [MY = 29–33], 2) there are no years where all temporary frost features lasted longer than their mean lifespan, and 3) local clouds, dust storms, and winds may affect the location of the sNPC edge

Wideband Photometric Magnitude Measurements of Saturn Made During the 2005-06 Apparition

The writer made 37 brightness measurements of Saturn + rings between Nov. 3, 2005 and March 16, 2006 using the B (blue), V (green), R (red), and I (infrared) filters. The selected normalized magnitudes of Saturn at a ring tilt angle of 18° are: B(1,0) = - 8.43 ± 0.03, V(1,0) = -9.48 ± 0.02, R(1,0) = -10.16 ± 0.04, and 1(1,0) = -10.28 ± 0.02. The selected phase angle coefficients of Saturn, in magnitudes/degree, are: cB = 0.022 ± 0.014, cV = 0.021 ± 0.008, cR = 0.027 ± 0.015, and cI = 0.018 ± 0.011

Wideband Photometry of Saturn in 2007-2008

The writer made 45 brightness measurements of Saturn + rings between Nov. 28, 2007 and April 24, 2008. The selected B(1,0), V(1,0), R(1,0) and I(1,0) values for Saturn + rings for b = 7° are: -8.10 ± 0.01, -9.14 ± 0.01, -9.77 ± 0.01 and -9.87 ± 0.02 respectively. The selected solar phase angle coefficients (in magnitudes/degree) are: 0.041 ± 0.006, 0.034 ± 0.005, 0.022 ± 0.007 and 0.027 ± 0.007 respectively. It is concluded that the angle between the ring plane and the Sun (B\u27) has as much affect on the results as the angle between the ring plane and the Earth (B). As a result of this, a new parameter, b, is defined as b = (B\u27 × B)1/2. Saturn’s opposition surge on Feb. 24 was 0.02 magnitudes in the V-filter

Near-Infrared Photometry of Mercury

This report summarizes 100 brightness measurements of Mercury made between May 2014 and September 2017 in the J and H near-infrared filters. Brightness models are reported for the J (solar phase angles between 52.3° and 124.5°) and H (solar phase angles between 38.6° and 133.0°) filters. Additional conclusions are as follows: Mercury’s brightness is within 0.1 magnitudes, at a given phase angle, for waxing and waning phases, and the geometric albedos at a solar phase angle of 0° are estimated to be 0.16 ± 0.03 and 0.24 ± 0.05 for the J and H filters, respectively