Monthly Observing Information
This page provides charts, and text concerning what is visible in the night sky during the month noted. All information is for Baton Rouge, Louisiana, but they can still provide useful information for most other areas of the U.S.A. Sky charts, Saturn ring plane, and Venus phase images are for Midnight, on the 15th day of the month. Sky charts are 100 degree field of view, and show objects down to 12th magnitude. Times in the Astronomy Lab 2 text information are in 24 hour format and have been adjusted for Daylight Savings Time. Subtract 12 hours from those over 12 to get the equivalent PM. RA and DEC given are for Epoch 2000.
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Baton Rouge Clear Sky Clock
Click on image for more info and details. This clock is for the Baton Rouge area only.
September
Moon Calendar
Sky charts
Saturn’s Ring Plane
Venus Phase
Begin End Date Moonrise Moonset Sunrise Sunset Twilight Twilight ------------ --------- --------- --------- --------- --------- --------- 9/1/2021 01:20 16:00 06:41 19:27 05:19 20:50 9/2/2021 02:10 16:51 06:42 19:26 05:20 20:48 9/3/2021 03:06 17:38 06:43 19:25 05:20 20:47 9/4/2021 04:06 18:20 06:43 19:24 05:21 20:45 9/5/2021 05:08 18:59 06:44 19:23 05:22 20:44 9/6/2021 06:11 19:35 06:44 19:21 05:23 20:43 9/7/2021 07:15 20:08 06:45 19:20 05:23 20:41 9/8/2021 08:18 20:41 06:45 19:19 05:24 20:40 9/9/2021 09:23 21:16 06:46 19:18 05:25 20:38 9/10/2021 10:29 21:52 06:46 19:16 05:25 20:37 9/11/2021 11:36 22:32 06:47 19:15 05:26 20:36 9/12/2021 12:44 23:18 06:48 19:14 05:27 20:34 9/13/2021 13:53 ------ 06:48 19:12 05:27 20:33 9/14/2021 14:58 00:09 06:49 19:11 05:28 20:32 9/15/2021 15:57 01:08 06:49 19:10 05:29 20:30 9/16/2021 16:49 02:11 06:50 19:09 05:29 20:29 9/17/2021 17:34 03:16 06:50 19:07 05:30 20:27 9/18/2021 18:12 04:20 06:51 19:06 05:31 20:26 9/19/2021 18:47 05:24 06:51 19:05 05:31 20:25 9/20/2021 19:18 06:23 06:52 19:03 05:32 20:23 9/21/2021 19:47 07:22 06:53 19:02 05:33 20:22 9/22/2021 20:16 08:18 06:53 19:01 05:33 20:21 9/23/2021 20:46 09:14 06:54 19:00 05:34 20:19 9/24/2021 21:17 10:09 06:54 18:58 05:35 20:18 9/25/2021 21:51 11:05 06:55 18:57 05:35 20:17 9/26/2021 22:29 12:01 06:55 18:56 05:36 20:15 9/27/2021 23:12 12:57 06:56 18:55 05:36 20:14 9/28/2021 24:00 13:51 06:57 18:53 05:37 20:13 9/29/2021 ------ 14:42 06:57 18:52 05:38 20:12 9/30/2021 00:53 15:31 06:58 18:51 05:38 20:10 '------' means the event does not occur on this date. Object Right ascensio Declination Azimuth Altitude Earth distance Sun distance ------------ -------------- ------------- ------------- ------------- --------------- --------------- Sun 11h 32m 45.1s +02° 56' 31" 334° 09' 01" -53° 40' 16" 0 0 Mercury 13h 06m 35.4s -10° 03' 29" 291° 25' 27" -48° 52' 29" 141,561,131 68,064,470 Venus 14h 09m 18.6s -14° 14' 14" 275° 30' 51" -37° 53' 55" 150,394,410 108,853,955 Mars 12h 01m 46.0s +00° 41' 50" 321° 42' 53" -52° 20' 39" 394,527,320 246,206,690 Jupiter 21h 47m 10.1s -14° 37' 37" 195° 19' 24" +43° 36' 18" 615,074,172 750,683,616 Saturn 20h 40m 11.9s -19° 12' 11" 212° 16' 14" +33° 26' 39" 1,377,360,689 1,487,253,347 Uranus 02h 48m 44.0s +15° 47' 21" 88° 37' 49" +30° 06' 55" 2,857,570,015 2,952,721,125 Neptune 23h 31m 35.5s -04° 20' 32" 155° 27' 20" +52° 28' 31" 4,325,910,948 4,476,309,146 Pluto 19h 46m 35.0s -22° 50' 51" 221° 46' 37" +23° 26' 12" 5,059,682,594 5,140,588,570 Moon 18h 41m 58.7s -26° 37' 34" 230° 15' 10" +10° 38' 23" 372,806 0 Object Rise: Tran Set: Phase Constl Magnitud ------------ ----- ----- ----- ------- --------- -------- Sun 05:49 12:00 18:11 0.00% Leo unknown Mercury 07:55 13:34 19:13 55.30% Vir 0.2 Venus 09:07 14:36 20:05 68.08% Vir -4.1 Mars 06:25 12:30 18:34 99.84% Vir 1.7 Jupiter 16:48 22:14 03:45 99.77% Cap -2.8 Saturn 15:53 21:08 02:26 99.87% Cap 0.4 Uranus 20:35 03:19 09:59 99.96% Ari 5.7 Neptune 18:07 23:59 05:54 100.00% Aqr 7.8 Pluto 15:08 20:13 01:21 99.98% Sgr 14.3 Moon 13:55 19:01 00:08 65.17% Sgr unknown Moon Data --------- Distance (km): 372,806.4 Distance (miles): 231,651.7 True Equatorial: 18h 45m 07.1s -25° 58' 48" Angular diameter: 0° 32' 10" Total libration (l,b): 3° 08' 53" , 3° 50' 27" Optical libration: 3° 07' 31" , 3° 49' 03" Physical libration: 0° 01' 22" , 0° 01' 24" Position Angle: 5° 42' 25" Pos. angle (bright limb): 72° 20' 26" Phase angle: 5° 42' 25" Age: 8.17 Mars Data --------- Declination of earth: 25° 41' 29" Declination of Sun: 24° 49' 58" Longitude of the central Meridian:262° 02' 13" Pos. Angle: 26° 54' 40" Jupiter Data ----------------- Declination of earth: 0° 39' 28" Declination of Sun: 0° 39' 01" Longitude of the central Meridian:115° 53' 56" Pos. Angle: 338° 24' 02" Saturn Data --------- Declination of earth: 19° 15' 18" Declination of Sun: 17° 38' 40" Longitude of the central Meridian: 0° 00' 00" Pos. Angle: 6° 46' 27" Name Month/Day RA Decl Hourly Rate ----------------------------- ------------ ---------- ---------- ----------- Aurigids 09/01 5.7 42.0 30 Northern Tau Aquarids 09/20 21.8 -6.0 15 Southern Piscids 09/20 0.4 0.0 10 Kappa Aquarids 09/21 22.5 -5.0 5 Daytime Sextantids 09/29 10.1 0.0 30 Southern Annual Andromedids 10/03 0.3 8.0 13
Information for this section is from TheSkyX Student Edition
Planet View Info Report for 9/ 1/2021 to 9/30/2021
Mercury
Date Rise Set RA Dec Elongation Ill Fr DIST(AU)
9/ 1/2021 8:34 20:29 12h08m01s -1°40'56" 23°44'00" 0.740 1.14648
9/ 8/2021 8:48 20:22 12h39m39s -6°10'50" 26°00'58" 0.659 1.05368
9/15/2021 8:55 20:11 13h05m55s -9°57'37" 26°44'40" 0.556 0.94950
9/22/2021 8:51 19:54 13h23m59s -12°35'32" 25°06'51" 0.417 0.83758
9/29/2021 8:27 19:27 13h28m06s -13°16'04" 19°33'38" 0.231 0.73046
Venus
Date Rise Set RA Dec Elongation Ill Fr DIST(AU)
9/ 1/2021 9:47 21:16 13h08m16s -7°26'20" 39°47'10" 0.729 1.10804
9/ 8/2021 9:58 21:10 13h38m10s -10°52'47" 41°07'54" 0.706 1.05790
9/15/2021 10:09 21:04 14h08m25s -14°08'41" 42°23'25" 0.681 1.00685
9/22/2021 10:20 21:00 14h39m09s -17°10'10" 43°32'51" 0.656 0.95503
9/29/2021 10:31 20:57 15h10m24s -19°53'28" 44°34'59" 0.630 0.90263
Mars
Date Rise Set RA Dec Elongation Ill Fr DIST(AU)
9/ 1/2021 7:38 20:02 11h28m21s 4°24'16" 12°14'39" 0.996 2.62608
9/ 8/2021 7:31 19:47 11h44m48s 2°35'12" 9°57'08" 0.997 2.63323
9/15/2021 7:24 19:31 12h01m18s 0°45'02" 7°39'41" 0.998 2.63719
9/22/2021 7:18 19:16 12h17m52s -1°05'43" 5°22'34" 0.999 2.63805
9/29/2021 7:11 19:01 12h34m33s -2°56'32" 3°06'21" 1.000 2.63588
Jupiter
Date Rise Set RA Dec Elongation Ill Fr DIST(AU)
9/ 1/2021 18:43 5:43 21h53m15s -14°06'02" 166°47'13" 0.999 4.03440
9/ 8/2021 18:13 5:12 21h50m00s -14°23'06" 159°11'00" 0.999 4.06582
9/15/2021 17:44 4:41 21h47m04s -14°38'03" 151°37'57" 0.998 4.11083
9/22/2021 17:14 4:10 21h44m34s -14°50'28" 144°10'03" 0.997 4.16845
9/29/2021 16:45 3:40 21h42m34s -15°00'00" 136°48'18" 0.995 4.23751
Saturn
Date Rise Set RA Dec Elongation Ill Fr DIST(AU)
9/ 1/2021 17:46 4:21 20h43m17s -19°00'14" 149°22'31" 0.999 9.08098
9/ 8/2021 17:18 3:52 20h41m45s -19°06'21" 142°12'45" 0.999 9.14600
9/15/2021 16:49 3:23 20h40m27s -19°11'26" 135°05'12" 0.999 9.22253
9/22/2021 16:21 2:54 20h39m25s -19°15'24" 128°00'21" 0.998 9.30923
9/29/2021 15:53 2:26 20h38m41s -19°18'10" 120°58'18" 0.998 9.40473
Uranus
Date Rise Set RA Dec Elongation Ill Fr DIST(AU)
9/ 1/2021 22:27 11:51 2h49m35s 15°51'21" 114°03'50" 0.999 19.30848
9/ 8/2021 21:59 11:23 2h49m14s 15°49'44" 120°56'18" 1.000 19.20365
9/15/2021 21:31 10:55 2h48m44s 15°47'26" 127°52'25" 1.000 19.10623
9/22/2021 21:03 10:27 2h48m05s 15°44'32" 134°51'58" 1.000 19.01772
9/29/2021 20:35 9:58 2h47m20s 15°41'03" 141°55'03" 1.000 18.93946
Neptune
Date Rise Set RA Dec Elongation Ill Fr DIST(AU)
9/ 1/2021 19:59 7:47 23h33m03s -4°11'01" 166°35'16" 1.000 28.94012
9/ 8/2021 19:31 7:18 23h32m21s -4°15'36" 173°30'27" 1.000 28.92132
9/15/2021 19:03 6:50 23h31m39s -4°20'14" 178°40'39" 1.000 28.91706
9/22/2021 18:35 6:22 23h30m56s -4°24'50" 172°16'22" 1.000 28.92742
9/29/2021 18:07 5:53 23h30m14s -4°29'17" 165°16'10" 1.000 28.95226
Pluto
Date Rise Set RA Dec Elongation Ill Fr DIST(AU)
9/ 1/2021 17:01 3:15 19h47m22s -22°48'13" 135°47'13" 1.000 33.62264
9/ 8/2021 16:33 2:47 19h46m56s -22°49'40" 128°54'23" 1.000 33.71614
9/15/2021 16:06 2:19 19h46m36s -22°50'53" 122°01'16" 1.000 33.81870
9/22/2021 15:38 1:51 19h46m21s -22°51'51" 115°08'04" 1.000 33.92883
9/29/2021 15:10 1:23 19h46m11s -22°52'33" 108°14'34" 1.000 34.04506
Planet Apsides Report for 2021
Mercury
9/ 5/2021 Aphelion Distance from Sun: 0.47 AU
Planet Conjunction/Opposition Report for 9/ 1/2021 to 9/30/2021
Neptune
Date Hour Event
9/14/2021 4 Opposition
Planet Data Report
Planet Mean Dist Period of Inclination Equatorial
From Sun Revolution Diameter
(AU) (km)
Mercury 0.39 88 days 7° 4880
Venus 0.72 224.7 days 3.4° 12100
Earth 1.00 365.24 days 0° 12756
Mars 1.52 687 days 1.9° 6794
Jupiter 5.20 11.86 years 1.3° 143200
Saturn 9.54 29.46 years 2.5° 120000
Uranus 19.18 84 years 0.8° 52290
Neptune 30.06 165 years 1.8° 50450
Pluto 39.44 248 years 17.2° 2200-2300
Moon Apsides Report for 9/ 1/2021 to 9/30/2021
Date Hour Apsis Distance (km) Diameter
9/11/2021 5 Perigee 368480 0.5405°
9/26/2021 17 Apogee 404657 0.4922°
Moon Nodes Report for 9/ 1/2021 to 9/30/2021
Date Time Node Illuminated Fraction
9/12/2021 11:34 Descending 0.35
9/26/2021 2:32 Ascending 0.77
Meteor Showers Report for 9/ 1/2021 to 9/30/2021
Date Meteor Shower ZHR RA DEC Illum. Frac. Longitude
9/ 8/2021 Piscids 10 0h36m 7° 0.04 166°
9/20/2021 Piscids 5 0h24m 0° 1.00 178°
Twilight Report for 9/ 1/2021 to 9/30/2021
Date Sun Astronomical Nautical Civil
Rise Set Begin End Begin End Begin End
9/ 1/2021 6:42 19:27 5:15 20:54 5:45 20:24 6:13 19:55
9/ 8/2021 6:45 19:19 5:20 20:44 5:49 20:15 6:17 19:47
9/15/2021 6:49 19:10 5:25 20:34 5:53 20:06 6:21 19:38
9/22/2021 6:53 19:01 5:29 20:25 5:58 19:57 6:25 19:29
9/29/2021 6:57 18:52 5:34 20:16 6:02 19:48 6:29 19:20
Information for this section is from Astronomy Lab 2.03
