What time is it on Mars? | Nagin Cox

133,732 views ・ 2017-02-24

TED


Please double-click on the English subtitles below to play the video.

00:12
So many of you have probably seen the movie "The Martian."
0
12874
3549
00:16
But for those of you who did not, it's a movie about an astronaut
1
16961
3817
00:20
who is stranded on Mars, and his efforts to stay alive
2
20802
4543
00:25
until the Earth can send a rescue mission to bring him back to Earth.
3
25369
4496
00:31
Gladly, they do re-establish communication
4
31025
3139
00:34
with the character, astronaut Watney, at some point
5
34188
2538
00:36
so that he's not as alone on Mars until he can be rescued.
6
36750
5271
00:42
So while you're watching the movie, or even if you haven't,
7
42546
2762
00:45
when you think about Mars,
8
45332
1548
00:46
you're probably thinking about how far away it is and how distant.
9
46904
4800
00:51
And, what might not have occurred to you is,
10
51728
2579
00:54
what are the logistics really like of working on another planet --
11
54331
3897
00:58
of living on two planets
12
58252
2246
01:00
when there are people on the Earth and there are rovers or people on Mars?
13
60522
5834
01:06
So think about when you have friends, families and co-workers
14
66380
4158
01:10
in California, on the West Coast or in other parts of the world.
15
70562
3158
01:14
When you're trying to communicate with them,
16
74045
2053
01:16
one of the things you probably first think about is:
17
76122
2438
01:18
wait, what time is it in California?
18
78584
2096
01:20
Will I wake them up? Is it OK to call?
19
80704
2595
01:23
So even if you're interacting with colleagues who are in Europe,
20
83703
3351
01:27
you're immediately thinking about:
21
87078
2042
01:29
What does it take to coordinate communication when people are far away?
22
89144
7000
01:36
So we don't have people on Mars right now, but we do have rovers.
23
96793
5584
01:42
And actually right now, on Curiosity, it is 6:10 in the morning.
24
102401
5105
01:47
So, 6:10 in the morning on Mars.
25
107530
2771
01:50
We have four rovers on Mars.
26
110696
2001
01:52
The United States has put four rovers on Mars since the mid-1990s,
27
112721
4007
01:56
and I have been privileged enough to work on three of them.
28
116752
3939
02:00
So, I am a spacecraft engineer, a spacecraft operations engineer,
29
120715
4521
02:05
at NASA's Jet Propulsion Laboratory in Los Angeles, California.
30
125260
4847
02:10
And these rovers are our robotic emissaries.
31
130676
4161
02:14
So, they are our eyes and our ears, and they see the planet for us
32
134861
6278
02:21
until we can send people.
33
141163
1833
02:23
So we learn how to operate on other planets through these rovers.
34
143020
5293
02:28
So before we send people, we send robots.
35
148337
4306
02:33
So the reason there's a time difference on Mars right now,
36
153146
3951
02:37
from the time that we're at
37
157121
1302
02:38
is because the Martian day is longer than the Earth day.
38
158447
3974
02:42
Our Earth day is 24 hours,
39
162774
2797
02:45
because that's how long it takes the Earth to rotate,
40
165595
3374
02:48
how long it takes to go around once.
41
168993
2001
02:51
So our day is 24 hours.
42
171018
1912
02:53
It takes Mars 24 hours and approximately 40 minutes to rotate once.
43
173306
6820
03:00
So that means that the Martian day is 40 minutes longer than the Earth day.
44
180150
6418
03:07
So teams of people who are operating the rovers on Mars, like this one,
45
187027
5155
03:12
what we are doing is we are living on Earth, but working on Mars.
46
192206
5412
03:17
So we have to think as if we are actually on Mars with the rover.
47
197642
5465
03:23
Our job, the job of this team, of which I'm a part of,
48
203474
3579
03:27
is to send commands to the rover to tell it what to do the next day.
49
207077
5929
03:33
To tell it to drive or drill or tell her whatever she's supposed to do.
50
213030
4029
03:37
So while she's sleeping -- and the rover does sleep at night
51
217373
4466
03:41
because she needs to recharge her batteries
52
221863
2370
03:44
and she needs to weather the cold Martian night.
53
224257
3896
03:48
And so she sleeps.
54
228177
1362
03:49
So while she sleeps, we work on her program for the next day.
55
229563
4768
03:54
So I work the Martian night shift.
56
234677
2982
03:57
(Laughter)
57
237683
1591
03:59
So in order to come to work on the Earth at the same time every day on Mars --
58
239298
6628
04:05
like, let's say I need to be at work at 5:00 p.m.,
59
245950
2404
04:08
this team needs to be at work at 5:00 p.m. Mars time every day,
60
248378
5569
04:13
then we have to come to work on the Earth 40 minutes later every day,
61
253971
7000
04:21
in order to stay in sync with Mars.
62
261962
2179
04:24
That's like moving a time zone every day.
63
264165
2952
04:27
So one day you come in at 8:00, the next day 40 minutes later at 8:40,
64
267141
5455
04:32
the next day 40 minutes later at 9:20,
65
272620
3269
04:35
the next day at 10:00.
66
275913
1589
04:37
So you keep moving 40 minutes every day,
67
277526
3578
04:41
until soon you're coming to work in the middle of the night --
68
281128
2989
04:44
the middle of the Earth night.
69
284141
1817
04:45
Right? So you can imagine how confusing that is.
70
285982
3618
04:49
Hence, the Mars watch.
71
289624
2152
04:51
(Laughter)
72
291800
1001
04:52
This weights in this watch have been mechanically adjusted
73
292825
3518
04:56
so that it runs more slowly.
74
296367
2528
04:58
Right? And we didn't start out --
75
298919
1889
05:00
I got this watch in 2004
76
300832
2226
05:03
when Spirit and Opportunity, the rovers back then.
77
303082
3304
05:06
We didn't start out thinking
78
306410
1606
05:08
that we were going to need Mars watches.
79
308040
2431
05:10
Right? We thought, OK, we'll just have the time on our computers
80
310495
4431
05:14
and on the mission control screens, and that would be enough.
81
314950
3648
05:18
Yeah, not so much.
82
318622
1381
05:20
Because we weren't just working on Mars time,
83
320027
2849
05:22
we were actually living on Mars time.
84
322900
3159
05:26
And we got just instantaneously confused about what time it was.
85
326083
4283
05:30
So you really needed something on your wrist to tell you:
86
330390
3793
05:34
What time is it on the Earth? What time is it on Mars?
87
334207
3291
05:37
And it wasn't just the time on Mars that was confusing;
88
337927
5894
05:43
we also needed to be able to talk to each other about it.
89
343845
4769
05:49
So a "sol" is a Martian day -- again, 24 hours and 40 minutes.
90
349157
5627
05:54
So when we're talking about something that's happening on the Earth,
91
354808
3195
05:58
we will say, today.
92
358027
1309
06:00
So, for Mars, we say, "tosol."
93
360048
2832
06:02
(Laughter)
94
362904
1838
06:05
Yesterday became "yestersol" for Mars.
95
365812
4517
06:10
Again, we didn't start out thinking, "Oh, let's invent a language."
96
370657
4507
06:15
It was just very confusing.
97
375188
1290
06:16
I remember somebody walked up to me and said,
98
376502
2181
06:18
"I would like to do this activity on the vehicle tomorrow, on the rover."
99
378707
3433
06:22
And I said, "Tomorrow, tomorrow, or Mars, tomorrow?"
100
382164
5111
06:27
We started this terminology because we needed a way to talk to each other.
101
387807
5052
06:32
(Laughter)
102
392883
1128
06:34
Tomorrow became "nextersol" or "solorrow."
103
394035
4276
06:39
Because people have different preferences for the words they use.
104
399036
3615
06:42
Some of you might say "soda" and some of you might say "pop."
105
402675
3376
06:46
So we have people who say "nextersol" or "solorrow."
106
406649
3206
06:50
And then something that I noticed after a few years of working on these missions,
107
410382
4724
06:55
was that the people who work on the rovers, we say "tosol."
108
415130
4652
07:00
The people who work on the landed missions that don't rove around,
109
420246
3534
07:03
they say "tosoul."
110
423804
1472
07:05
So I could actually tell what mission you worked on from your Martian accent.
111
425778
4719
07:10
(Laughter)
112
430521
3250
07:13
So we have the watches and the language, and you're detecting a theme here, right?
113
433795
3860
07:17
So that we don't get confused.
114
437679
1996
07:20
But even the Earth daylight could confuse us.
115
440239
3807
07:24
If you think that right now, you've come to work
116
444489
2339
07:26
and it's the middle of the Martian night
117
446852
2095
07:28
and there's light streaming in from the windows
118
448971
3298
07:32
that's going to be confusing as well.
119
452293
2148
07:34
So you can see from this image of the control room
120
454901
2505
07:37
that all of the blinds are down.
121
457430
2269
07:39
So that there's no light to distract us.
122
459723
3003
07:42
The blinds went down all over the building about a week before landing,
123
462750
4352
07:47
and they didn't go up until we went off Mars time.
124
467126
3267
07:50
So this also works for the house, for at home.
125
470847
3181
07:54
I've been on Mars time three times, and my husband is like,
126
474052
2773
07:56
OK, we're getting ready for Mars time.
127
476849
1815
07:58
And so he'll put foil all over the windows and dark curtains and shades
128
478688
6202
08:04
because it also affects your families.
129
484914
3147
08:08
And so here I was living in kind of this darkened environment, but so was he.
130
488085
4879
08:13
And he'd gotten used to it.
131
493525
1296
08:14
But then I would get these plaintive emails from him when he was at work.
132
494845
3642
08:19
Should I come home? Are you awake?
133
499077
3292
08:22
What time is it on Mars?
134
502393
3130
08:25
And I decided, OK, so he needs a Mars watch.
135
505547
2498
08:28
(Laughter)
136
508069
1535
08:29
But of course, it's 2016, so there's an app for that.
137
509628
4434
08:34
(Laughter)
138
514086
1278
08:35
So now instead of the watches, we can also use our phones.
139
515388
4614
08:40
But the impact on families was just across the board;
140
520420
4140
08:44
it wasn't just those of us who were working on the rovers
141
524584
3662
08:48
but our families as well.
142
528270
2214
08:50
This is David Oh, one of our flight directors,
143
530508
2479
08:53
and he's at the beach in Los Angeles with his family at 1:00 in the morning.
144
533011
4474
08:57
(Laughter)
145
537509
1423
08:58
So because we landed in August
146
538956
2980
09:01
and his kids didn't have to go back to school until September,
147
541960
4446
09:06
they actually went on to Mars time with him for one month.
148
546430
4748
09:11
They got up 40 minutes later every day.
149
551202
4769
09:15
And they were on dad's work schedule.
150
555995
2183
09:18
So they lived on Mars time for a month and had these great adventures,
151
558202
3975
09:22
like going bowling in the middle of the night
152
562201
2097
09:24
or going to the beach.
153
564322
1318
09:25
And one of the things that we all discovered
154
565969
3359
09:29
is you can get anywhere in Los Angeles
155
569352
3988
09:33
at 3:00 in the morning when there's no traffic.
156
573364
3553
09:36
(Laughter)
157
576941
1474
09:38
So we would get off work,
158
578439
1192
09:39
and we didn't want to go home and bother our families,
159
579655
3115
09:42
and we were hungry, so instead of going locally to eat something,
160
582794
3190
09:46
we'd go, "Wait, there's this great all-night deli in Long Beach,
161
586008
3564
09:49
and we can get there in 10 minutes!"
162
589596
2242
09:51
So we would drive down -- it was like the 60s, no traffic.
163
591862
2721
09:54
We would drive down there, and the restaurant owners would go,
164
594607
3755
09:58
"Who are you people?
165
598386
2162
10:01
And why are you at my restaurant at 3:00 in the morning?"
166
601241
4173
10:05
So they came to realize that there were these packs of Martians,
167
605778
4890
10:11
roaming the LA freeways, in the middle of the night --
168
611481
4665
10:17
in the middle of the Earth night.
169
617108
2023
10:19
And we did actually start calling ourselves Martians.
170
619155
4797
10:24
So those of us who were on Mars time would refer to ourselves as Martians,
171
624401
5606
10:30
and everyone else as Earthlings.
172
630031
2853
10:32
(Laughter)
173
632908
1300
10:34
And that's because when you're moving a time-zone every day,
174
634232
5695
10:39
you start to really feel separated from everyone else.
175
639951
5813
10:45
You're literally in your own world.
176
645788
3919
10:50
So I have this button on that says, "I survived Mars time. Sol 0-90."
177
650524
6925
10:57
And there's a picture of it up on the screen.
178
657473
2745
11:00
So the reason we got these buttons is because we work on Mars time
179
660242
5629
11:05
in order to be as efficient as possible with the rover on Mars,
180
665895
5049
11:10
to make the best use of our time.
181
670968
2290
11:13
But we don't stay on Mars time for more than three to four months.
182
673282
3886
11:17
Eventually, we'll move to a modified Mars time, which is what we're working now.
183
677192
4268
11:22
And that's because it's hard on your bodies, it's hard on your families.
184
682199
4657
11:26
In fact, there were sleep researchers who actually were studying us
185
686880
4882
11:31
because it was so unusual for humans to try to extend their day.
186
691786
5037
11:37
And they had about 30 of us
187
697147
1290
11:38
that they would do sleep deprivation experiments on.
188
698461
3626
11:42
So I would come in and take the test and I fell asleep in each one.
189
702111
3563
11:45
And that was because, again, this eventually becomes hard on your body.
190
705698
6642
11:52
Even though it was a blast.
191
712364
3315
11:55
It was a huge bonding experience with the other members on the team,
192
715703
4514
12:00
but it is difficult to sustain.
193
720241
2840
12:04
So these rover missions are our first steps out into the solar system.
194
724063
6185
12:10
We are learning how to live on more than one planet.
195
730272
5073
12:15
We are changing our perspective to become multi-planetary.
196
735369
5076
12:20
So the next time you see a Star Wars movie,
197
740763
2795
12:23
and there are people going from the Dagobah system to Tatooine,
198
743582
3675
12:27
think about what it really means to have people spread out so far.
199
747281
5490
12:32
What it means in terms of the distances between them,
200
752795
3062
12:35
how they will start to feel separate from each other
201
755881
3820
12:39
and just the logistics of the time.
202
759725
3224
12:43
We have not sent people to Mars yet, but we hope to.
203
763757
4552
12:48
And between companies like SpaceX and NASA
204
768333
3839
12:52
and all of the international space agencies of the world,
205
772196
3489
12:55
we hope to do that in the next few decades.
206
775709
3767
12:59
So soon we will have people on Mars, and we truly will be multi-planetary.
207
779500
5825
13:05
And the young boy or the young girl
208
785820
2412
13:08
who will be going to Mars could be in this audience or listening today.
209
788256
7000
13:16
I have wanted to work at JPL on these missions since I was 14 years old
210
796021
5602
13:21
and I am privileged to be a part of it.
211
801647
2222
13:23
And this is a remarkable time in the space program,
212
803893
4054
13:27
and we are all in this journey together.
213
807971
3174
13:31
So the next time you think you don't have enough time in your day,
214
811169
5211
13:36
just remember, it's all a matter of your Earthly perspective.
215
816404
4778
13:41
Thank you.
216
821206
1151
13:42
(Applause)
217
822381
4114
About this website

This site will introduce you to YouTube videos that are useful for learning English. You will see English lessons taught by top-notch teachers from around the world. Double-click on the English subtitles displayed on each video page to play the video from there. The subtitles scroll in sync with the video playback. If you have any comments or requests, please contact us using this contact form.

https://forms.gle/WvT1wiN1qDtmnspy7