2. Day
Shkiah:
Netz Hachamah:
Alot Hashachar:
Tzeit Hakochovim:

3. Night
Morning Twilight
Evening Twilight
Sunrise
Horizon

4. Alot Hashachar: - Dawn
The time that marks the beginning of the twilight before sunrise. It is recognized by the presence of weak sunlight, while the sun itself is still below the horizon. Dawn should not be confused with sunrise, which is the moment when the leading edge of the sun itself appears above the horizon.

5. Netz Hachamah: - Sunrise
The instant at which the upper edge of the Sun appears above the horizon in the east.

6. Shkiah: - Sunset
The daily disappearance of the sun below the horizon as a result of the Earth's rotation.

7. Dusk
The beginning of darkness in the evening, and occurs after twilight.

8. Tzeit Hakochovim: The time when three stars are visible in the sky and nightfall is complete.

9. Day Sha’ah Zemanit – Jewish hour Sunrise until Sunset 12
Proportional hour, i.e. an hour according to halachah. Total daylight hours divided by 12.
Sha’ah Zemanit – Jewish hour
Sunrise until Sunset 12

10. October, 4 2010 – Philadelphia Netz Hachama – Sunrise: 7:00 AM
Example:
October, – Philadelphia
Netz Hachama – Sunrise: 7:00 AM
Shkiah – Sunset: 6:36 PM
11 hours and 36 minutes
Length of the day for October, in Philadelphia
11 x 60 = 660 minutes
660 minutes +
36 minutes
696 minutes  11 hours and 36 minutes

11. One Jewish hour on October 4, 2010 in Philadelphia is 58 minutes.12
696 60 -
------ 96 -
----- 96
One Jewish hour on October 4, 2010 in Philadelphia is 58 minutes.

12. Day 58 minutes = 1 Jewish hour Sunrise Sunset 7:00 am 7:58 am 8:56 am
12:48 pm
1:46 pm
2:44 pm
3:42 pm
4:40 pm
5:38 pm
6:36 pm
1 hr
2 hr
3 hr
4 hr
5 hr
6 hr
7 hr
8 hr
9 hr
10 hr
11 hr
12 hr

13. Other important times:
Chatzot: Midday; the halfway point between sunrise and sunset.
Minchah Gedolah: Half a shaah zmanit after chatzot.
Minchah Ketanah: Nine and a half shaot zmaniot after sunrise.
Plag Haminchah: Ten and three quarters shaot zmaniyot after sunrise.

14. Chatzot: Midday; the halfway point between sunrise and sunset.
To calculate: 6 x Jewish hour
Example:
6 x 58 minutes = 348 minutes
348/60 = 5 remainder 48
Chatzot is 5 hours and 48 minutes after sunrise
7:00 am + 5 hours 48 minutes = 12:48 pm
Chatzot
Sunrise
Sunset
7:00 am
7:58 am
8:56 am
9:54 am
10:52 am
11:50 am
12:48 pm
1:46 pm
2:44 pm
3:42 pm
4:40 pm
5:38 pm
6:36 pm
1 hr
2 hr
3 hr
4 hr
5 hr
6 hr
7 hr
8 hr
9 hr
10 hr
11 hr
12 hr
12:48 pm
6 hr

15. Minchah Gedolah: Half a shaah zmanit after chatzot.
To calculate: 6.5 x Jewish hour
Example:
6.5 x 58 minutes = 377 minutes
377/60 = 6 remainder 17
Minchah Gedolah is 6 hours and 17 minutes after sunrise
7:00 am + 6 hours 17 minutes = 1:17 pm
Minchah Gedolah
Sunrise
Sunset
7:00 am
7:58 am
8:56 am
9:54 am
10:52 am
11:50 am
12:48 pm
1:46 pm
2:44 pm
3:42 pm
4:40 pm
5:38 pm
6:36 pm
1 hr
2 hr
3 hr
4 hr
5 hr
6 hr
7 hr
8 hr
9 hr
10 hr
11 hr
12 hr

16. Minchah Ketanah: Nine and a half shaot zmaniot after sunrise.
To calculate: 9.5 x Jewish hour
Example:
9.5 x 58 minutes = 551 minutes
551/60 = 9 remainder 11
Minchah Ketanah is 9 hours and 11 minutes after sunrise
7:00 am + 9 hours 11 minutes = 4:11 pm
Minchah Ketanah
Sunrise
Sunset
7:00 am
7:58 am
8:56 am
9:54 am
10:52 am
11:50 am
12:48 pm
1:46 pm
2:44 pm
3:42 pm
4:40 pm
5:38 pm
6:36 pm
1 hr
2 hr
3 hr
4 hr
5 hr
6 hr
7 hr
8 hr
9 hr
10 hr
11 hr
12 hr

17. Plag Haminchah: Ten and three quarters shaot zmaniyot after sunrise.
To calculate: x Jewish hour
Example:
10.75 x 58 minutes = 623 minutes
623/60 = 10 remainder 23
Plag Hamincha is 10 hours and 23 minutes after sunrise
7:00 am + 10 hours 23 minutes = 5:23 pm
Plag Hamincha
Sunrise
Sunset
7:00 am
7:58 am
8:56 am
9:54 am
10:52 am
11:50 am
12:48 pm
1:46 pm
2:44 pm
3:42 pm
4:40 pm
5:38 pm
6:36 pm
1 hr
2 hr
3 hr
4 hr
5 hr
6 hr
7 hr
8 hr
9 hr
10 hr
11 hr
12 hr

18. Night Sha’ah Zemanit – Jewish hour Sunset until Sunrise 12
Proportional hour, i.e. an hour according to halachah. Total nighttime hours divided by 12.
Sha’ah Zemanit – Jewish hour
Sunset until Sunrise 12

19. October, 4 - 5 2010 – Philadelphia Netz Hachama – Sunset: 6:36 PM
Example:
October, – Philadelphia
Netz Hachama – Sunset: 6:36 PM
Shkiah – Sunrise: 7:00 AM
12 hours and 24 minutes
Length of the night for October, in Philadelphia
12 x 60 = 720 minutes
720 minutes +
24 minutes
744 minutes  12 hours and 24 minutes

20. 6 2 12
744 72 -
------ 24 -
----- 24
One Jewish hour on October , 2010 in Philadelphia is 1 hour and 2 minutes.

21. Night 1 hour and 2 minutes = 1 Jewish hour Sunset Sunrise 6:36 pm
12:48 am
1:50 am
2:52 am
3:54 am
4:56 am
5:58 am
7:00 am
1 hr
2 hr
3 hr
4 hr
5 hr
6 hr
7 hr
8 hr
9 hr
10 hr
11 hr
12 hr

22. Terms for night:
Chatzot
Midnight; the halfway point between sunset and sunrise.
Shmira
The night is divided up into three sections, each section being called a shmira.

23. Midnight; the halfway point between sunset and sunrise.
Chatzot
Midnight; the halfway point between sunset and sunrise.
To calculate: 6 x Jewish hour
Example:
6 x 62 minutes = 372 minutes
372/60 = 6 remainder 12
Chatzot is 6 hours and 12 minutes after sunset
6:36 pm + 6 hours 12 minutes = 12:48 am
Chatzot
Sunset
Sunrise
6:36 pm
7:38 pm
8:40 pm
9:42 pm
10:44 pm
11:46 pm
12:48 am
1:50 am
2:52 am
3:54 am
4:56 am
5:58 am
7:00 am
1 hr
2 hr
3 hr
4 hr
5 hr
6 hr
7 hr
8 hr
9 hr
10 hr
11 hr
12 hr
12:48 am
6 hr

24. Shmira
The night is divided up into three sections, each section being called a shmira.
To calculate end of first shmira: 4 x Jewish hour
Example:
4 x 62 minutes = 248 minutes
248/60 = 4 remainder 8
The first shmira ends 4 hours and 8 minutes after sunset
6:36 pm + 4 hours 8 minutes = 10:44 pm
First Shmira
Sunset
Sunrise
6:36 pm
7:38 pm
8:40 pm
9:42 pm
10:44 pm
11:46 pm
12:48 am
1:50 am
2:52 am
3:54 am
4:56 am
5:58 am
7:00 am
1 hr
2 hr
3 hr
4 hr
5 hr
6 hr
7 hr
8 hr
9 hr
10 hr
11 hr
12 hr
10:44 pm
4 hr

25. Shmira
The night is divided up into three sections, each section being called a shmira.
To calculate end of second shmira: 8 x Jewish hour
Example:
8 x 62 minutes = 596 minutes
496/60 = 8 remainder 16
The second shmira ends 8 hours and 16 minutes after sunset
6:36 pm + 8 hours 16 minutes = 2:52 am
Second Shmira
Sunset
Sunrise
6:36 pm
7:38 pm
8:40 pm
9:42 pm
10:44 pm
11:46 pm
12:48 am
1:50 am
2:52 am
3:54 am
4:56 am
5:58 am
7:00 am
1 hr
2 hr
3 hr
4 hr
5 hr
6 hr
7 hr
8 hr
9 hr
10 hr
11 hr
12 hr
2:52 am
8 hr

26. First Shmira
Second Shmira
Third Shmira
Sunset
Sunrise
6:36 pm
7:38 pm
8:40 pm
9:42 pm
10:44 pm
11:46 pm
12:48 am
1:50 am
2:52 am
3:54 am
4:56 am
5:58 am
7:00 am
1 hr
2 hr
3 hr
4 hr
5 hr
6 hr
7 hr
8 hr
9 hr
10 hr
11 hr
12 hr
10:44 pm
4 hr
2:52 am
8 hr