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Archive for April 1, 2019

04/01/2019 – Ephemeris – Previewing April skies

April 1, 2019 Comments off

Ephemeris for April Fools Day, Monday, April 1st. Today the Sun will be up for 12 hours and 46 minutes, setting at 8:10, and it will rise tomorrow at 7:22. The Moon, half way from last quarter to new, will rise at 6:37 tomorrow morning.

Last year we were fooled by an abundance of snow in April. Hopefully we won’t be tricked again. Daylight hours in the Interlochen/Traverse City area and will increase from 12 hours and 46 minutes today to 14 hours 11 minutes on the 30th. The altitude, or angle, of the Sun above the southern horizon at local noon will ascend from 50 degrees today to 60 degrees on the 30th. The altitude of the Sun in the Straits area will be a degree lower, but their daylight hours will be a bit longer. The actual time of local apparent noon this month for the Interlochen/Traverse City area, when the Sun passes due south, will be about 1:43 p.m. This month Mars will be our only evening planet.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

April Evening Star Chart

April Evening Star Chart

Star Chart for April 2019 (10 p.m. EDT April 15, 2019). Created using my LookingUp program. Click on image to enlarge.

The planets and stars are plotted for the 15th at 10 p.m. EST in the evening and 6 a.m. for the morning chart. These are the chart times. Note that Traverse City is located approximately 45 minutes behind our time meridian, West 75° longitude. (An hour 45 minutes behind our daylight saving time meridian during EDT). To duplicate the star positions on a planisphere you may have to set it to 1 hour 45 minutes earlier than the current time.

Note the chart times of 10 p.m. and 5 a.m. are for the 15th. For each week before the 15th add ½ hour (28 minutes if you’re picky). For each week after the 15th subtract ½ hour. The planet positions are updated each Wednesday on this blog. For planet positions on dates other than the 15th, check the Wednesday planet posts on this blog.

April Morning Star Chart

April Morning Star Chart

Star Chart for April mornings 2019 (5 a.m. EST April 15, 2019). Created using my LookingUp program. Click on image to enlarge.

For a list of constellation names to go with the abbreviations click here.

  • Pointer stars at the front of the bowl of the Big Dipper point to Polaris the North Star.
  • Leaky dipper drips on Leo
  • Follow the arc of the handle of the Big Dipper to the star Arcturus, and
  • Extend like a spike to Spica,
  • The Summer Triangle is in red.
  • LyrR is the radiant of the Lyrid meteor shower that peaks on the 22nd.

Twilight Limits, Nautical and Astronomical

      EDT        
Traverse
City
Morning twilight Evening twilight Dark night Moon
Date Astro. Nautical Nautical Astro. Start End Illum.
2019-04-01 5h47m 6h24m 21h17m 21h53m 21h53m 5h47m 0.13
2019-04-02 5h45m 6h22m 21h18m 21h55m 21h55m 5h45m 0.07
2019-04-03 5h43m 6h20m 21h20m 21h57m 21h57m 5h43m 0.03
2019-04-04 5h41m 6h18m 21h21m 21h58m 21h58m 5h41m 0
2019-04-05 5h38m 6h16m 21h22m 22h00m 22h00m 5h38m 0
2019-04-06 5h36m 6h14m 21h24m 22h01m 22h01m 5h36m 0.02
2019-04-07 5h34m 6h12m 21h25m 22h03m 22h48m 5h34m 0.06
2019-04-08 5h32m 6h10m 21h27m 22h05m 23h54m 5h32m 0.12
2019-04-09 5h30m 6h08m 21h28m 22h06m 5h30m 0.2
2019-04-10 5h27m 6h06m 21h30m 22h08m 1h00m 5h27m 0.3
2019-04-11 5h25m 6h04m 21h31m 22h10m 2h04m 5h25m 0.41
2019-04-12 5h23m 6h02m 21h33m 22h11m 3h03m 5h23m 0.53
2019-04-13 5h21m 6h00m 21h34m 22h13m 3h55m 5h21m 0.64
2019-04-14 5h19m 5h58m 21h36m 22h15m 4h40m 5h19m 0.75
2019-04-15 5h16m 5h56m 21h37m 22h16m 0.85
2019-04-16 5h14m 5h54m 21h39m 22h18m 0.93
2019-04-17 5h12m 5h52m 21h40m 22h20m 0.93
2019-04-18 5h10m 5h50m 21h42m 22h22m 0.98
2019-04-19 5h07m 5h48m 21h43m 22h24m 1
2019-04-20 5h05m 5h46m 21h45m 22h25m 0.99
2019-04-21 5h03m 5h44m 21h46m 22h27m 22h27m 23h19m 0.96
2019-04-22 5h01m 5h42m 21h48m 22h29m 22h29m 0.9
2019-04-23 4h59m 5h40m 21h49m 22h31m 22h31m 0h24m 0.82
2019-04-24 4h56m 5h38m 21h51m 22h33m 22h33m 1h24m 0.74
2019-04-25 4h54m 5h36m 21h52m 22h34m 22h34m 2h16m 0.64
2019-04-26 4h52m 5h35m 21h54m 22h36m 22h36m 3h01m 0.54
2019-04-27 4h50m 5h33m 21h55m 22h38m 22h38m 3h39m 0.45
2019-04-28 4h48m 5h31m 21h57m 22h40m 22h40m 4h12m 0.35
2019-04-29 4h45m 5h29m 21h58m 22h42m 22h42m 4h41m 0.26
2019-04-30 4h43m 5h27m 22h00m 22h44m 22h44m 4h43m

0.18

Twilight calendar was generated using Cartes du Ciel (Sky Charts).

See my blog post: Twilight Zone for the definitions of the different periods of twilight here: https://bobmoler.wordpress.com/2018/09/27/.

NASA Calendar of Planetary Events

   Date			Local Time	Event
Apr	1	Mo		        Venus: 34.6° W
 	2	Tu	12:17 AM	Moon-Venus: 3° N
 	2	Tu	07:01 PM	Moon-Mercury: 4° N
 	5	Fr	04:50 AM	New Moon
 	9	Tu	02:40 AM	Moon-Mars: 5° N
 	9	Tu	11:43 AM	Moon-Aldebaran: 2.2° S
 	11	Th	02:59 PM	Mercury Elongation: 27.7° W
 	11	Th	07:59 PM	Moon North Dec.: 22° N
 	12	Fr	02:08 PM	Moon Ascending Node
 	12	Fr	03:06 PM	First Quarter
 	13	Sa	04:12 PM	Moon-Beehive: 0.2° N
 	14	Su	08:08 PM	Mars-Aldebaran: 6.5° N
 	15	Mo	04:22 AM	Moon-Regulus: 2.7° S
 	16	Tu	02:03 PM	Mercury-Venus: 4.3° N
 	16	Tu	06:02 PM	Moon Perigee: 364200 km
 	19	Fr	07:12 AM	Full Moon
 	22	Mo	07:58 PM	Lyrid Shower: ZHR = 20
 	22	Mo	08:06 PM	Uranus Conjunction
 	23	Tu	07:36 AM	Moon-Jupiter: 1.8° S
 	24	We	05:22 PM	Moon South Dec.: 22.1° S
 	25	Th	10:38 AM	Moon-Saturn: 0.4° N
 	25	Th	11:02 AM	Moon Descending Node
 	26	Fr	06:18 PM	Last Quarter
 	28	Su	02:20 PM	Moon Apogee: 404600 km
May	1	We		        Venus: 27.8° W
All event times are given for UTC-5 hr: Eastern Standard or UTC-4 hr: Daylight Saving Time starting April 10th.

Sky Events Calendar by Fred Espenak and Sumit Dutta (NASA’s GSFC),
http://eclipse.gsfc.nasa.gov/SKYCAL/SKYCAL.html.

If you go to the above site you can print out a list like the above for the entire year or calendar pages for your time zone.

Sun and Moon Rising and Setting Events

Ephemeris of Sky Events for NMC Observatory

April, 2019 – Local time zone: EDT

Date

Sun

Twilight*

Moon

Illum

   

Rise

Set

Hours

End

Start

Phase

R/S**

Time

Fractn

Mon

1

07:23a

08:09p

12:45

09:14p

06:19a

 

Rise

06:37a

10%

Tue

2

07:21a

08:10p

12:49

09:15p

06:17a

 

Rise

07:02a

5%

Wed

3

07:20a

08:12p

12:52

09:17p

06:15a

 

Rise

07:26a

2%

Thu

4

07:18a

08:13p

12:55

09:18p

06:13a

 

Rise

07:50a

0%

Fri

5

07:16a

08:14p

12:58

09:19p

06:11a

New

Set

08:37p

1%

Sat

6

07:14a

08:15p

13:01

09:21p

06:09a

 

Set

09:41p

3%

 

Sun

7

07:12a

08:17p

13:04

09:22p

06:07a

 

Set

10:47p

7%

Mon

8

07:11a

08:18p

13:07

09:24p

06:05a

 

Set

11:53p

13%

Tue

9

07:09a

08:19p

13:10

09:25p

06:03a

 

Set

12:59a

21%

Wed

10

07:07a

08:20p

13:13

09:27p

06:01a

 

Set

02:03a

31%

Thu

11

07:05a

08:22p

13:16

09:28p

05:59a

 

Set

03:02a

41%

Fri

12

07:03a

08:23p

13:19

09:30p

05:57a

F Qtr

Set

03:54a

52%

Sat

13

07:02a

08:24p

13:22

09:31p

05:55a

 

Set

04:39a

64%

 

Sun

14

07:00a

08:25p

13:25

09:33p

05:53a

 

Set

05:18a

74%

Mon

15

06:58a

08:27p

13:28

09:34p

05:51a

 

Set

05:52a

84%

Tue

16

06:57a

08:28p

13:31

09:35p

05:49a

 

Set

06:23a

91%

Wed

17

06:55a

08:29p

13:34

09:37p

05:47a

 

Set

06:52a

97%

Thu

18

06:53a

08:30p

13:37

09:38p

05:45a

 

Set

07:22a

100%

Fri

19

06:51a

08:32p

13:40

09:40p

05:43a

Full

Rise

08:55p

99%

Sat

20

06:50a

08:33p

13:43

09:42p

05:41a

 

Rise

10:08p

97%

 

Sun

21

06:48a

08:34p

13:45

09:43p

05:39a

 

Rise

11:18p

92%

Mon

22

06:46a

08:35p

13:48

09:45p

05:38a

 

Rise

12:24a

85%

Tue

23

06:45a

08:37p

13:51

09:46p

05:36a

 

Rise

01:23a

77%

Wed

24

06:43a

08:38p

13:54

09:48p

05:34a

 

Rise

02:15a

68%

Thu

25

06:42a

08:39p

13:57

09:49p

05:32a

 

Rise

03:00a

59%

Fri

26

06:40a

08:40p

14:00

09:51p

05:30a

L Qtr

Rise

03:38a

49%

Sat

27

06:39a

08:41p

14:02

09:52p

05:28a

 

Rise

04:11a

40%

 

Sun

28

06:37a

08:43p

14:05

09:54p

05:26a

 

Rise

04:40a

31%

Mon

29

06:36a

08:44p

14:08

09:55p

05:24a

 

Rise

05:06a

23%

Tue

30

06:34a

08:45p

14:11

09:57p

05:23a

 

Rise

05:30a

15%

* Nautical Twilight

** Moonrise or moonset, whichever occurs between sunset and sunrise