August 2019.
Lunar highlightName: Alphonsus
Location: Near the centre of the Moon.
Type: Crater, with a large central peak.
Size: 121 km
Best seen: At First Quarter or six days after Full Moon.
Notes: Named for 13th-century king Alfonso X of Castile. Several tiny, dark-haloed craters can be seen on its floor; these are volcanic vents surrounded by deposits of dark ash. With Ptolemaeus and Arzachel, forms a magnificent trio of craters visible with binoculars.
Deep-sky highlight for August: Ptolemy's Cluster (NGC 6475, Messier 7)
Near the border between Scorpius and Sagittarius and within the main flow of the Milky Way lies a naked-eye nebulous patch, revealed in binoculars as a large, scattered cluster of bright stars. lt was recorded as far back as the second century by the Egyptian astronomer Ptolemy, hence its nickname. La Caille in the 1750s drew attention to the striking linear arrangements of its stars, describing it as a "group of 15 to 20 stars in a square". Other observers comment on the cluster's colourful appearance, noting that several stars are tinted yellow and blue. The accompanying photograph hints at the complex field within which it lies, including the swallow-shaped dark nebula B 287 immediately to the south. For a challenge, try to spot nearby NGC 6453, a globular cluster about one-third of a degree away.
Caption: August 01-15 before sunrise
Caption: August 08-13 after sunset
Caption: August 01-31 evening sky
Celestial almanac d Event 01 New Moon (05:12) Mars near the Moon 02 Moon at perigee (09:10, 359 397 km) Regulus near the Moon Callisto at maximum separation from Jupiter Titan at maximum separation from Saturn Mountain Sanctuary Park Star Party (02-04) 03 Titan at maximum separation from Saturn 04 Callisto at maximum separation from Jupiter 05 Titan at maximum separation from Saturn 06 Callisto at maximum separation from Jupiter 07 First Quarter Moon (19:31) ASSA Annual General Meeting 08 Lunar X feature forms (05:43) Venus at perihelion 09 National Women's Day 10 Mercury at greatest western elongation (19[degrees]) Jupiter near the Moon 11 Jupiter stationary Titan at maximum separation from Saturn 12 Saturn near the Moon (occultation seen from eastern Indonesia, most of Australia, northern New Zealand, Polynesia (except Hawaii) and Melanesia) Moon furthest south (-22.4[degrees]) Moon at descending node (16:45) Uranus stationary 13 Pluto near the Moon (occultation seen from north-eastern South America, Ascension Island, central and eastern Africa, and southern Arabian Peninsula) Titan at maximum separation from Saturn 14 Venus at superior conjunction 15 Full Moon (14:29) Mercury at ascending node Callisto at maximum separation from Jupiter 17 Moon at apogee (12:51, 406 243 km) Neptune near the Moon 18 Mars near Regulus 19 Titan at maximum separation from Saturn 20 Mercury at perihelion 21 Uranus near the Moon Venus near Regulus Callisto at maximum separation from Jupiter 22 Juno at conjuction 23 Last Quarter Moon (16:56) 24 Aldebaran near the Moon Venus near Mars (17.4') 25 Titan at maximum separation from Saturn 26 Moon occults eta Gem Moon furthest north (+22.5[degrees]) Mars at aphelion 27 Moon at ascending node (03:50) Callisto at maximum separation from Jupiter Titan at maximum separation from Saturn 29 Mercury near Regulus Callisto at maximum separation from Jupiter Titan at maximum separation from Saturn 30 New Moon (12:37) Black Moon Moon at perigee (17:59, 357 175 km) Mercury near the Moon Venus near the Moon Mars near the Moon Regulus near the Moon Mercury at greatest latitude north Venus at greatest latitude north Planet visibility Mercury can be seen at dawn until late in the month. Venus and Mars are too near the Sun to be seen during August. Jupiter and Saturn can be seen at sunset until before dawn. Stellar occultations The Moon occults eta Gem on the morning of August 26. The table below gives the time of disappearance (D) and reappearance (R) for selected locations. Location D R Harare 03:40:53 04:38:56 Johannesburg 03:56:35 04:21:51 Sun rise and set, position and distance d Bloem. Cape Town Durban Harare rise set rise set rise set rise set 01 06:59 17:44 07:39 18:06 06:42 17:23 06:23 17:42 04 06:57 17:46 07:36 18:08 06:39 17:25 06:21 17:43 07 06:55 17:47 07:34 18:11 06:37 17:27 06:20 17:44 10 06:52 17:49 07:31 18:13 06:34 17:29 06:18 17:45 13 06:50 17:51 07:28 18:15 06:32 17:30 06:17 17:45 16 06:47 17:52 07:24 18:17 06:29 17:32 06:15 17:46 19 06:44 17:54 07:21 18:19 06:26 17:34 06:13 17:47 22 06:41 17:55 07:17 18:21 06:23 17:35 06:11 17:47 25 06:38 17:57 07:14 18:23 06:20 17:37 06:09 17:48 28 06:35 17:58 07:10 18:25 06:16 17:39 06:07 17:48 31 06:31 18:00 07:06 18:27 06:13 17:40 06:04 17:49 d Jo'burg Declination Con Distance at 02:00 (AU) rise set 01 06:47 17:41 +18[degrees] 12' 27.1" Cnc 1.015123 04 06:45 17:43 +17 26 31.4 Cnc 1.014730 07 06:43 17:44 +16 38 03.1 Cnc 1.014288 10 06:41 17:46 +15 47 10.5 Cnc 1.013807 13 06:39 17:47 +14 54 01.9 Leo 1.013295 16 06:36 17:48 +13 58 45.6 Leo 1.012759 19 06:33 17:50 +13 01 29.6 Leo 1.012199 22 06:31 17:51 +12 02 22.0 Leo 1.011617 25 06:28 17:52 +11 01 31.2 Leo 1.011007 28 06:25 17:54 +09 59 05.3 Leo 1.010365 31 06:22 17:55 +08 55 13.2 Leo 1.009683 Con = constellation (see Table 11 on p 89), Distance = Sun-Earth distance in AU. Also see rise/set times on pp 72-73. Moon rise and set d Bloem. Cape Town Durban rise set rise set rise set 01 07:14 18:09 07:57 18:32 06:56 17:48 02 08:06 19:22 08:46 19:48 07:46 18:58 03 08:52 20:31 09:29 20:59 08:33 20:10 04 09:33 21:37 10:08 22:08 09:14 21:17 05 10:12 22:41 10:44 23:15 09:53 22:22 06 10:50 23:44 11:19 -:- 10:30 23:25 07 11:28 -:- 11:55 00:20 11:08 -:- 08 12:07 00:45 12:32 01:24 11:47 00:27 09 12:49 01:46 13:12 02:26 12:28 01:27 10 13:34 02:44 13:55 03:27 13:13 02:26 11 14:22 03:41 14:42 04:24 14:00 03:23 12 15:13 04:34 15:33 05:18 14:51 04:16 13 16:05 05:24 16:26 06:07 15:44 05:06 14 16:59 06:08 17:21 06:51 16:38 05:50 15 17:53 06:49 18:17 07:30 17:32 06:31 16 18:46 07:26 19:12 08:05 18:25 07:08 17 19:38 08:00 20:06 08:37 19:18 07:41 18 20:30 08:32 21:01 09:07 20:10 08:13 19 21:22 09:03 21:55 09:35 21:02 08:43 20 22:15 09:33 22:49 10:04 21:55 09:14 21 23:08 10:05 23:45 10:33 22:49 09:45 22 -:- 10:38 -:- 11:04 23:45 10:18 23 00:04 11:15 00:43 11:39 -:- 10:55 24 01:01 11:57 01:42 12:19 00:43 11:36 25 02:01 12:44 02:44 13:05 01:42 12:23 26 03:01 13:38 03:45 13:59 02:43 13:17 27 04:01 14:39 04:45 15:00 03:43 14:17 28 04:58 15:45 05:41 16:07 04:40 15:24 29 05:51 16:55 06:32 17:19 05:33 16:34 30 06:39 18:05 07:18 18:32 06:21 17:44 31 07:23 19:14 08:01 19:47 07:05 18:54 d Harare Jo'burg rise set rise set 01 06:34 18:09 07:01 18:07 02 07:29 19:14 07:54 19:18 03 08:21 20:19 08:41 20:25 04 09:08 21:20 09:24 21:30 05 09:52 22:19 10:05 22:33 06 10:36 23:16 10:44 23:34 07 11:19 -:- 11:23 -:- 08 12:03 00:13 12:04 00:34 09 12:48 01:09 12:47 01:33 10 13:36 02:04 13:32 02:31 11 14:25 02:59 14:21 03:27 12 15:16 03:51 15:11 04:20 13 16:08 04:41 16:04 05:10 14 16:59 05:28 16:57 05:55 15 17:50 06:12 17:50 06:37 16 18:39 06:52 18:42 07:15 17 19:27 07:30 19:33 07:50 18 20:15 08:06 20:24 08:23 19 21:02 08:41 21:14 08:55 20 21:50 09:17 22:05 09:27 21 22:39 09:53 22:58 09:59 22 23:30 10:30 23:52 10:34 23 -:- 11:11 -:- 11:12 24 00:23 11:56 00:48 11:54 25 01:20 12:46 01:47 12:43 26 02:18 13:42 02:47 13:37 27 03:18 14:42 03:47 14:38 28 04:16 15:46 04:44 15:44 29 05:13 16:52 05:38 16:52 30 06:06 17:57 06:28 18:01 31 06:55 19:00 07:14 19:08 For Port Elizabeth subtract 28m from Cape Town; for Bulawayo add 9m to Harare. Jupiter's Galilean moons d Time Event 02 01:23.6 Europa is occulted 03 19:29.7 Europa transit starts 21:39.2 Europa's shadow transit starts 21:56.7 Europa transit ends 04 00:09.4 Europa's shadow transit ends 19:07.2 Ganymede is occulted 21:31.4 Ganymede reappears (occulted) 23:31.5 Ganymede is eclipsed 05 02:03.0 Ganymede reappears from eclipse 02:45.1 Io is occulted 19:19.5 Europa reappears from eclipse 06 00:06.4 Io transit starts 01:12.2 Io's shadow transit starts 02:18.0 Io transit ends 03:24.2 Io's shadow transit ends 21:12.5 Io is occulted 07 00:33.5 Io reappears from eclipse 18:33.9 Io transit starts 19:40.9 Io's shadow transit starts 20:45.5 Io transit ends 21:52.9 Io's shadow transit ends 08 19:02.3 Io reappears from eclipse 10 21:56.7 Europa transit starts 11 00:15.9 Europa's shadow transit starts 00:24.1 Europa transit ends 02:46.4 Europa's shadow transit ends 22:48.5 Ganymede is occulted 12 01:14.3 Ganymede reappears (occulted) 21:55.5 Europa reappears from eclipse 13 01:57.1 Io transit starts 03:07.1 Io's shadow transit starts 23:03.4 Io is occulted 14 02:28.7 Io reappears from eclipse 20:24.9 Io transit starts 21:35.8 Io's shadow transit starts 22:36.5 Io transit ends 23:47.8 Io's shadow transit ends 15 19:54.2 Ganymede's shadow transit ends 20:57.6 Io reappears from eclipse 16 18:16.5 Io's shadow transit ends 18 00:26.1 Europa transit starts 02:52.8 Europa's shadow transit starts 02:53.9 Europa transit ends 19 02:33.4 Ganymede is occulted 19:32.4 Europa is occulted 20 00:31.4 Europa reappears from eclipse 21 00:55.4 Io is occulted 18:42.7 Europa's shadow transit ends 22:17.0 Io transit starts 23:30.8 Io's shadow transit starts 22 00:28.5 Io transit ends 01:42.7 Io's shadow transit ends 18:46.4 Ganymede transit ends 19:23.6 Io is occulted 21:22.8 Ganymede's shadow transit starts 22:53.0 Io reappears from eclipse 23:55.0 Ganymede's shadow transit ends 23 18:56.7 Io transit ends 20:11.4 Io's shadow transit ends 26 22:03.6 Europa is occulted 27 00:33.0 Europa reappears from occultation 00:35.3 Europa is eclipsed 28 18:43.3 Europa transit ends 18:48.7 Europa's shadow transit starts 21:20.2 Europa's shadow transit ends 29 00:10.1 Io transit starts 01:25.8 Io's shadow transit starts 20:12.2 Ganymede transit starts 21:17.0 Io is occulted 22:39.7 Ganymede transit ends 30 00:48.4 Io reappears from eclipse 01:22.2 Ganymede's shadow transit starts 18:38.6 Io transit starts 19:54.5 Io's shadow transit starts 20:50.1 Io transit ends 22:06.3 Io's shadow transit ends 31 19:17.2 Io reappears from eclipse
![]() ![]() ![]() ![]() | |
Title Annotation: | Alphonsus and Ptolemy's Cluster |
---|---|
Publication: | Sky Guide Africa South |
Date: | Jan 1, 2019 |
Words: | 2278 |
Previous Article: | July 2019. |
Next Article: | Star charts for winter: June 01 at 00:00, July 01 at 22:00, and August 01 at 20:00. |
Topics: |