﻿1
00:00:00,084 --> 00:00:02,550
[upbeat music]

2
00:00:02,550 --> 00:00:04,470
>> Preston: What's up for July?

3
00:00:04,470 --> 00:00:08,040
The planets at dawn,
the dog days of summer,

4
00:00:08,040 --> 00:00:11,670
and the teapot points to
the center of the Milky Way.

5
00:00:11,670 --> 00:00:14,550
The planet's Mars, Jupiter, and Saturn

6
00:00:14,550 --> 00:00:17,160
dominate morning skies in July.

7
00:00:17,160 --> 00:00:19,980
Venus is there as well, but
appears low in the east,

8
00:00:19,980 --> 00:00:23,100
so you'll need a clear view
toward the horizon to see it.

9
00:00:23,100 --> 00:00:25,740
The planets are spread out
across the morning sky,

10
00:00:25,740 --> 00:00:28,200
accompanied by bright stars Capella,

11
00:00:28,200 --> 00:00:30,300
Aldebaran, and Fomalhaut.

12
00:00:30,300 --> 00:00:33,690
On the 20th, look for the
half-full last quarter moon

13
00:00:33,690 --> 00:00:35,914
between Mars and Jupiter,

14
00:00:35,914 --> 00:00:36,840
and the following morning,

15
00:00:36,840 --> 00:00:39,877
you'll find the moon
sitting right next to Mars.

16
00:00:39,877 --> 00:00:41,070
[meteor whooshes]

17
00:00:41,070 --> 00:00:43,620
July is a time for sweltering hot weather

18
00:00:43,620 --> 00:00:45,210
here in the Northern Hemisphere,

19
00:00:45,210 --> 00:00:46,710
and you may have heard this time of year

20
00:00:46,710 --> 00:00:49,860
referred to as the "dog days of summer."

21
00:00:49,860 --> 00:00:52,260
That phrase actually dates
back to ancient times

22
00:00:52,260 --> 00:00:55,980
and has to do with the brightest
star in the sky, Sirius.

23
00:00:55,980 --> 00:00:57,810
At the peak of summer, the Sun lies

24
00:00:57,810 --> 00:01:00,270
in the same part of the sky as Sirius,

25
00:01:00,270 --> 00:01:01,800
which the ancient Greeks and Romans

26
00:01:01,800 --> 00:01:05,520
associated with the dog-shaped
constellation Canis Major,

27
00:01:05,520 --> 00:01:07,080
just as we do today.

28
00:01:07,080 --> 00:01:09,360
Sirius is its most prominent star,

29
00:01:09,360 --> 00:01:12,150
and it's sometimes called "the dog star."

30
00:01:12,150 --> 00:01:15,570
In ancient Greek, Sirius
means "the scorcher,"

31
00:01:15,570 --> 00:01:17,340
and both the Greeks and Romans believed

32
00:01:17,340 --> 00:01:20,190
the blazing bright star's
proximity in the sky

33
00:01:20,190 --> 00:01:23,160
added to the Sun's heat
during that time of year,

34
00:01:23,160 --> 00:01:25,500
making it even more oppressive.

35
00:01:25,500 --> 00:01:28,740
So they called this hot
time of year the "dog days."

36
00:01:28,740 --> 00:01:30,600
Of course, today we know the only star

37
00:01:30,600 --> 00:01:34,290
close enough to affect our
temperatures on Earth is the Sun,

38
00:01:34,290 --> 00:01:36,120
and the heat we experience in July

39
00:01:36,120 --> 00:01:37,920
is the result of the Northern Hemisphere

40
00:01:37,920 --> 00:01:40,140
being tilted toward the Sun.

41
00:01:40,140 --> 00:01:42,720
This yields longer days
and more direct sunlight,

42
00:01:42,720 --> 00:01:44,790
and thus, warmer weather.

43
00:01:44,790 --> 00:01:47,340
The situation is reversed
in the Southern Hemisphere,

44
00:01:47,340 --> 00:01:49,999
where July is right in
the middle of winter.

45
00:01:49,999 --> 00:01:51,360
[meteor whooshes]

46
00:01:51,360 --> 00:01:53,970
Facing southward on July
nights after sunset,

47
00:01:53,970 --> 00:01:56,970
you'll find a sky teeming
with bright stars.

48
00:01:56,970 --> 00:01:59,430
Looking in that direction in
the evening this time of year,

49
00:01:59,430 --> 00:02:02,760
you're facing the center of
our galaxy, the Milky Way,

50
00:02:02,760 --> 00:02:04,410
and there are quite a
number of bright stars

51
00:02:04,410 --> 00:02:06,420
in that part of the sky, particularly

52
00:02:06,420 --> 00:02:09,570
in the constellations
Scorpius and Sagittarius.

53
00:02:09,570 --> 00:02:11,700
Now, if you find yourself
under dark skies,

54
00:02:11,700 --> 00:02:15,030
you'll be able to fully
enjoy the Milky Way core,

55
00:02:15,030 --> 00:02:18,750
densely packed with stars
and clouds of dust and gas.

56
00:02:18,750 --> 00:02:21,030
It's dazzling this time
of year and it's visible

57
00:02:21,030 --> 00:02:24,030
toward the south as soon
as it gets fully dark out.

58
00:02:24,030 --> 00:02:25,770
But even if you're under urban skies

59
00:02:25,770 --> 00:02:27,810
too bright to observe the Milky Way,

60
00:02:27,810 --> 00:02:31,110
the group of stars in
Sagittarius known as the Teapot

61
00:02:31,110 --> 00:02:34,200
will help you pinpoint
its location on the sky.

62
00:02:34,200 --> 00:02:38,130
The Teapot is a well known
asterism, or pattern of stars,

63
00:02:38,130 --> 00:02:40,740
and like Scorpius the scorpion nearby,

64
00:02:40,740 --> 00:02:43,440
once you're familiar with
it, it's hard not to see

65
00:02:43,440 --> 00:02:45,750
a teapot there in the sky.

66
00:02:45,750 --> 00:02:48,660
The galaxy's core lies
just right of the stars

67
00:02:48,660 --> 00:02:50,490
in the Teapot's "spout."

68
00:02:50,490 --> 00:02:52,950
Over the course of the
night, it appears to tilt,

69
00:02:52,950 --> 00:02:56,400
as though its spout is
pouring out a cosmic "cuppa."

70
00:02:56,400 --> 00:02:58,440
And under dark skies, the Milky Way

71
00:02:58,440 --> 00:03:02,490
appears as a plume of steam
rising from the spout.

72
00:03:02,490 --> 00:03:04,530
So here's hoping you get a chance to enjoy

73
00:03:04,530 --> 00:03:07,680
the Milky Way in July, or at
least that you find your way

74
00:03:07,680 --> 00:03:10,744
to the galaxy's core thanks to the Teapot.

75
00:03:10,744 --> 00:03:12,210
[meteor whooshes]

76
00:03:12,210 --> 00:03:14,433
Here are the phases of the moon for July.

77
00:03:15,660 --> 00:03:18,030
Stay up to date with
all of NASA's missions

78
00:03:18,030 --> 00:03:21,543
to explore the solar system
and beyond at nasa.gov.

79
00:03:23,400 --> 00:03:26,340
I'm Preston Dyches from NASA's
Jet Propulsion Laboratory,

80
00:03:26,340 --> 00:03:28,140
and that's What's Up for this month.

