0:00:13.879,0:00:17.428
So many of you have probably seen[br]the movie "The Martian."

0:00:18.066,0:00:21.883
But for those of you who did not,[br]it's a movie about an astronaut

0:00:21.907,0:00:26.450
who is stranded on Mars,[br]and his efforts to stay alive

0:00:26.474,0:00:30.970
until the Earth can send a rescue mission[br]to bring him back to Earth.

0:00:32.130,0:00:35.269
Gladly, they do re-establish communication

0:00:35.293,0:00:37.831
with the character,[br]astronaut Watney, at some point

0:00:37.855,0:00:43.126
so that he's not as alone[br]on Mars until he can be rescued.

0:00:43.651,0:00:46.413
So while you're watching the movie,[br]or even if you haven't,

0:00:46.437,0:00:47.985
when you think about Mars,

0:00:48.009,0:00:52.809
you're probably thinking about[br]how far away it is and how distant.

0:00:52.833,0:00:55.412
And, what might not[br]have occurred to you is,

0:00:55.436,0:00:59.333
what are the logistics really like[br]of working on another planet --

0:00:59.357,0:01:01.603
of living on two planets

0:01:01.627,0:01:07.461
when there are people on the Earth[br]and there are rovers or people on Mars?

0:01:07.485,0:01:13.073
So think about when you have friends,[br]families and co-workers

0:01:13.097,0:01:16.796
in California, on the West Coast[br]or in other parts of the world.

0:01:16.820,0:01:18.873
When you're trying[br]to communicate with them,

0:01:18.897,0:01:21.335
one of the things[br]you probably first think about is:

0:01:21.359,0:01:23.455
wait, what time is it in California?

0:01:23.479,0:01:26.074
Will I wake them up? Is it OK to call?

0:01:26.478,0:01:29.829
So even if you're interacting[br]with colleagues who are in Europe,

0:01:29.853,0:01:31.895
you're immediately thinking about:

0:01:31.919,0:01:38.919
What does it take to coordinate[br]communication when people are far away?

0:01:39.808,0:01:45.392
So we don't have people on Mars[br]right now, but we do have rovers.

0:01:45.716,0:01:52.082
And actually right now, on Curiosity,[br]it is 6:10 in the morning.

0:01:52.305,0:01:55.076
So, 6:10 in the morning on Mars.

0:01:55.471,0:01:57.472
We have four rovers on Mars.

0:01:57.496,0:02:01.503
The United States has put four rovers[br]on Mars since the mid-1990s,

0:02:01.527,0:02:05.466
and I have been privileged enough[br]to work on three of them.

0:02:05.490,0:02:10.011
So, I am a spacecraft engineer,[br]a spacecraft operations engineer,

0:02:10.035,0:02:14.882
at NASA's Jet Propulsion Laboratory[br]in Los Angeles, California.

0:02:15.451,0:02:19.612
And these rovers[br]are our robotic emissaries.

0:02:19.636,0:02:25.914
So, they are our eyes and our ears,[br]and they see the planet for us

0:02:25.938,0:02:27.771
until we can send people.

0:02:27.795,0:02:33.088
So we learn how to operate[br]on other planets through these rovers.

0:02:33.112,0:02:37.418
So before we send people, we send robots.

0:02:37.921,0:02:41.872
So the reason there's a time difference[br]on Mars right now,

0:02:41.896,0:02:44.138
from the time that we're at

0:02:44.162,0:02:48.136
is because the Martian day[br]is longer than the Earth day.

0:02:48.489,0:02:51.286
Our Earth day is 24 hours,

0:02:51.310,0:02:54.684
because that's how long it takes[br]the Earth to rotate,

0:02:54.708,0:02:56.709
how long it takes to go around once.

0:02:56.733,0:02:58.645
So our day is 24 hours.

0:02:59.061,0:03:05.881
It takes Mars 24 hours and approximately[br]40 minutes to rotate once.

0:03:05.905,0:03:12.547
So that means that the Martian day[br]is 40 minutes longer than the Earth day.

0:03:12.982,0:03:17.844
So teams of people who are operating[br]the rovers on Mars, like this one --

0:03:17.868,0:03:19.869
this is one of our teams that I'm part of,

0:03:19.893,0:03:21.967
I usually sit at this table over here --

0:03:21.991,0:03:27.403
what we are doing is we are living[br]on Earth, but working on Mars.

0:03:27.427,0:03:32.892
So we have to think as if we are actually[br]on Mars with the rover.

0:03:33.259,0:03:36.838
Our job, the job of this team,[br]of which I'm a part of,

0:03:36.862,0:03:42.791
is to send commands to the rover[br]to tell it what to do the next day.

0:03:42.815,0:03:46.844
To tell it to drive or drill[br]or tell her whatever she's supposed to do.

0:03:47.158,0:03:51.624
So while she's sleeping --[br]and the rover does sleep at night

0:03:51.648,0:03:54.018
because she needs[br]to recharge her batteries

0:03:54.042,0:03:57.938
and she needs to weather[br]the cold Martian night.

0:03:57.962,0:03:59.324
And so she sleeps.

0:03:59.348,0:04:04.116
So while she sleeps, we work[br]on her program for the next day.

0:04:04.462,0:04:07.444
So I work the Martian night shift.

0:04:07.468,0:04:09.059
(Laughter)

0:04:09.083,0:04:15.711
So in order to come to work on the Earth[br]at the same time every day on Mars --

0:04:15.735,0:04:18.139
like, let's say I need to be[br]at work at 5:00 p.m.,

0:04:18.163,0:04:23.732
this team needs to be at work[br]at 5:00 p.m. Mars time every day,

0:04:23.756,0:04:30.756
then we have to come to work[br]on the Earth 40 minutes later every day,

0:04:31.747,0:04:33.926
in order to stay in sync with Mars.

0:04:33.950,0:04:36.902
That's like moving a time zone every day.

0:04:36.926,0:04:42.381
So one day you come in at 8:00,[br]the next day 40 minutes later at 8:40,

0:04:42.405,0:04:45.674
the next day 40 minutes later at 9:20,

0:04:45.698,0:04:47.287
the next day at 10:00.

0:04:47.311,0:04:50.889
So you keep moving 40 minutes every day,

0:04:50.913,0:04:53.902
until soon you're coming to work[br]in the middle of the night --

0:04:53.926,0:04:55.743
the middle of the Earth night.

0:04:55.767,0:04:59.385
Right? So you can imagine[br]how confusing that is.

0:04:59.409,0:05:01.561
Hence, the Mars watch.

0:05:01.585,0:05:03.409
(Laughter)

0:05:03.433,0:05:04.448
(Applause)

0:05:04.472,0:05:06.102
I think they're going to zoom in.

0:05:06.126,0:05:09.386
(Applause)

0:05:09.410,0:05:13.798
This weights in this watch[br]have been mechanically adjusted

0:05:13.822,0:05:16.350
so that it runs more slowly.

0:05:16.374,0:05:18.263
Right? And we didn't start out --

0:05:18.287,0:05:20.513
I got this watch in 2004

0:05:20.537,0:05:23.841
when Spirit and Opportunity,[br]the rovers back then.

0:05:23.865,0:05:25.471
We didn't start out thinking

0:05:25.495,0:05:27.926
that we were going to need Mars watches.

0:05:27.950,0:05:32.381
Right? We thought, OK,[br]we'll just have the time on our computers

0:05:32.405,0:05:36.053
and on the mission control screens,[br]and that would be enough.

0:05:36.077,0:05:37.458
Yeah, not so much.

0:05:37.482,0:05:40.331
Because we weren't just[br]working on Mars time,

0:05:40.355,0:05:43.514
we were actually living on Mars time.

0:05:43.538,0:05:47.821
And we got just instantaneously confused[br]about what time it was.

0:05:47.845,0:05:51.638
So you really needed something[br]on your wrist to tell you:

0:05:51.662,0:05:54.953
What time is it on the Earth?[br]What time is it on Mars?

0:05:55.382,0:06:01.276
And it wasn't just the time on Mars[br]that was confusing;

0:06:01.300,0:06:06.069
we also needed to be able[br]to talk to each other about it.

0:06:06.612,0:06:12.239
So a "sol" is a Martian day --[br]again, 24 hours and 40 minutes.

0:06:12.263,0:06:15.458
So when we're talking about something[br]that's happening on the Earth,

0:06:15.482,0:06:16.791
we will say, today.

0:06:17.503,0:06:20.335
So, for Mars, we say, "tosol."

0:06:20.359,0:06:23.098
(Laughter)

0:06:23.267,0:06:27.784
Yesterday became "yestersol" for Mars.

0:06:28.112,0:06:32.619
Again, we didn't start out thinking,[br]"Oh, let's invent a language."

0:06:32.643,0:06:33.933
It was just very confusing.

0:06:33.957,0:06:36.138
I remember somebody[br]walked up to me and said,

0:06:36.162,0:06:39.595
"I would like to do this activity[br]on the vehicle tomorrow, on the rover."

0:06:39.619,0:06:44.730
And I said, "Tomorrow, tomorrow,[br]or Mars, tomorrow?"

0:06:45.262,0:06:50.314
We started this terminology because[br]we needed a way to talk to each other.

0:06:50.338,0:06:51.759
(Laughter)

0:06:51.783,0:06:56.059
Tomorrow became "nextersol" or "solorrow."

0:06:56.891,0:07:00.506
Because people have different preferences[br]for the words they use.

0:07:00.530,0:07:04.343
Some of you might say "soda"[br]and some of you might say "pop."

0:07:05.004,0:07:08.210
So we have people who say[br]"nextersol" or "solorrow."

0:07:08.737,0:07:13.461
And then something that I noticed after[br]a few years of working on these missions,

0:07:13.485,0:07:18.137
was that the people who work[br]on the rovers, we say "tosol."

0:07:18.601,0:07:22.135
The people who work on the[br]landed missions that don't rove around,

0:07:22.159,0:07:23.631
they say "tosoul."

0:07:24.133,0:07:28.852
So I could actually tell what mission[br]you worked on from your Martian accent.

0:07:28.876,0:07:30.500
(Laughter)

0:07:30.524,0:07:34.196
(Applause)

0:07:34.220,0:07:38.080
So we have the watches and the language,[br]and you're detecting a theme here, right?

0:07:38.104,0:07:40.100
So that we don't get confused.

0:07:40.664,0:07:44.471
But even the Earth daylight[br]could confuse us.

0:07:44.674,0:07:47.253
If you think that right now,[br]you've come to work

0:07:47.277,0:07:49.372
and it's the middle of the Martian night

0:07:49.396,0:07:52.694
and there's light streaming in[br]from the windows

0:07:52.718,0:07:54.866
that's going to be confusing as well.

0:07:55.326,0:07:57.831
So you can see from[br]this image of the control room

0:07:57.855,0:08:00.124
that all of the blinds are down.

0:08:00.148,0:08:03.151
So that there's no light to distract us.

0:08:03.175,0:08:08.027
The blinds went down all over the building[br]about a week before landing,

0:08:08.051,0:08:11.318
and they didn't go up[br]until we went off Mars time.

0:08:11.772,0:08:14.953
So this also works[br]for the house, for at home.

0:08:14.977,0:08:17.750
I've been on Mars time three times,[br]and my husband is like,

0:08:17.774,0:08:19.589
OK, we're getting ready for Mars time.

0:08:19.613,0:08:25.815
And so he'll put foil all over the windows[br]and dark curtains and shades

0:08:25.839,0:08:28.986
because it also affects your families.

0:08:29.010,0:08:33.889
And so here I was living in kind of[br]this darkened environment, but so was he.

0:08:34.450,0:08:35.746
And he'd gotten used to it.

0:08:35.770,0:08:39.412
But then I would get these plaintive[br]emails from him when he was at work.

0:08:40.002,0:08:43.294
Should I come home? Are you awake?

0:08:43.318,0:08:46.448
What time is it on Mars?

0:08:46.472,0:08:48.970
And I decided, OK,[br]so he needs a Mars watch.

0:08:48.994,0:08:50.529
(Laughter)

0:08:50.553,0:08:54.987
But of course, it's 2016,[br]so there's an app for that.

0:08:55.011,0:08:56.289
(Laughter)

0:08:56.313,0:09:00.927
So now instead of the watches,[br]we can also use our phones.

0:09:01.345,0:09:05.485
But the impact on families[br]was just across the board;

0:09:05.509,0:09:09.171
it wasn't just those of us[br]who were working on the rovers

0:09:09.195,0:09:11.409
but our families as well.

0:09:11.433,0:09:13.912
This is David Oh,[br]one of our flight directors,

0:09:13.936,0:09:18.410
and he's at the beach in Los Angeles[br]with his family at 1:00 in the morning.

0:09:18.434,0:09:19.857
(Laughter)

0:09:19.881,0:09:22.861
So because we landed in August

0:09:22.885,0:09:27.331
and his kids didn't have to go back[br]to school until September,

0:09:27.355,0:09:32.103
they actually went on to Mars time[br]with him for one month.

0:09:32.127,0:09:36.896
They got up 40 minutes later every day.

0:09:36.920,0:09:39.103
And they were on dad's work schedule.

0:09:39.127,0:09:43.102
So they lived on Mars time for a month[br]and had these great adventures,

0:09:43.126,0:09:45.223
like going bowling[br]in the middle of the night

0:09:45.247,0:09:46.565
or going to the beach.

0:09:46.894,0:09:50.253
And one of the things[br]that we all discovered

0:09:50.277,0:09:54.265
is you can get anywhere in Los Angeles

0:09:54.289,0:09:57.842
at 3:00 in the morning[br]when there's no traffic.

0:09:57.866,0:09:59.340
(Laughter)

0:09:59.364,0:10:01.156
So we would get off work,

0:10:01.180,0:10:04.295
and we didn't want to go home[br]and bother our families,

0:10:04.319,0:10:07.509
and we were hungry, so instead of[br]going locally to eat something,

0:10:07.533,0:10:11.097
we'd go, "Wait, there's this great[br]all-night deli in Long Beach,

0:10:11.121,0:10:13.363
and we can get there in 10 minutes!"

0:10:13.387,0:10:16.108
So we would drive down --[br]it was like the 60s, no traffic.

0:10:16.132,0:10:19.887
We would drive down there,[br]and the restaurant owners would go,

0:10:19.911,0:10:22.742
"Who are you people?

0:10:22.766,0:10:26.939
And why are you at my restaurant[br]at 3:00 in the morning?"

0:10:27.303,0:10:31.692
So they came to realize[br]that there were these packs of Martians --

0:10:31.716,0:10:32.982
(Laughter)

0:10:33.006,0:10:37.671
roaming the LA freeways,[br]in the middle of the night --

0:10:38.633,0:10:40.656
in the middle of the Earth night.

0:10:40.680,0:10:45.477
And we did actually[br]start calling ourselves Martians.

0:10:45.926,0:10:51.532
So those of us who were on Mars time[br]would refer to ourselves as Martians,

0:10:51.556,0:10:54.409
and everyone else as Earthlings.

0:10:54.433,0:10:55.733
(Laughter)

0:10:55.757,0:11:01.452
And that's because when you're moving[br]a time-zone every day,

0:11:01.476,0:11:07.289
you start to really feel separated[br]from everyone else.

0:11:07.313,0:11:11.232
You're literally in your own world.

0:11:12.049,0:11:18.974
So I have this button on that says,[br]"I survived Mars time. Sol 0-90."

0:11:18.998,0:11:21.743
And there's a picture of it[br]up on the screen.

0:11:21.767,0:11:27.396
So the reason we got these buttons[br]is because we work on Mars time

0:11:27.420,0:11:32.469
in order to be as efficient as possible[br]with the rover on Mars,

0:11:32.493,0:11:34.783
to make the best use of our time.

0:11:34.807,0:11:38.693
But we don't stay on Mars time[br]for more than three to four months.

0:11:38.717,0:11:43.593
Eventually, we'll move to a modified Mars[br]time, which is what we're working now.

0:11:44.524,0:11:49.181
And that's because it's hard on[br]your bodies, it's hard on your families.

0:11:49.205,0:11:54.087
In fact, there were sleep researchers[br]who actually were studying us

0:11:54.111,0:11:59.148
because it was so unusual for humans[br]to try to extend their day.

0:11:59.357,0:12:02.548
And so, I wore an [actigraph].

0:12:02.572,0:12:03.862
And they had about 30 of us

0:12:03.886,0:12:07.512
that they would do[br]sleep deprivation experiments on.

0:12:07.536,0:12:11.099
So I would come in and take the test[br]and I fell asleep in each one.

0:12:11.123,0:12:17.765
And that was because, again,[br]this eventually becomes hard on your body.

0:12:17.789,0:12:21.104
Even though it was a blast.

0:12:21.128,0:12:25.642
It was a huge bonding experience[br]with the other members on the team,

0:12:25.666,0:12:28.506
but it is difficult to sustain.

0:12:29.488,0:12:35.673
So these rover missions are our first[br]steps out into the solar system.

0:12:35.697,0:12:40.770
We are learning how to live[br]on more than one planet.

0:12:40.794,0:12:45.870
We are changing our perspective[br]to become multi-planetary.

0:12:46.188,0:12:48.983
So the next time you see[br]a Star Wars movie,

0:12:49.007,0:12:52.682
and there are people going[br]from the Dagobah system to Tatooine,

0:12:52.706,0:12:58.196
think about what it really means to have[br]people spread out so far.

0:12:58.220,0:13:01.282
What it means in terms of[br]the distances between them,

0:13:01.306,0:13:05.126
how they will start to feel[br]separate from each other

0:13:05.150,0:13:08.374
and just the logistics of the time.

0:13:09.182,0:13:13.734
We have not sent people[br]to Mars yet, but we hope to.

0:13:13.758,0:13:17.597
And between companies like SpaceX and NASA

0:13:17.621,0:13:21.110
and all of the international[br]space agencies of the world,

0:13:21.134,0:13:24.901
we hope to do that[br]in the next few decades.

0:13:24.925,0:13:30.750
So soon we will have people on Mars,[br]and we truly will be multi-planetary.

0:13:31.245,0:13:33.657
And the young boy or the young girl

0:13:33.681,0:13:40.681
who will be going to Mars could be[br]in this audience or listening today.

0:13:41.446,0:13:47.048
I have wanted to work at JPL[br]on these missions since I was 14 years old

0:13:47.072,0:13:49.294
and I am privileged to be a part of it.

0:13:49.318,0:13:53.372
And this is a remarkable time[br]in the space program,

0:13:53.396,0:13:56.570
and we are all in this journey together.

0:13:56.594,0:14:01.805
So the next time you think[br]you don't have enough time in your day,

0:14:01.829,0:14:06.607
just remember, it's all a matter[br]of your Earthly perspective.

0:14:06.631,0:14:07.782
Thank you.

0:14:07.806,0:14:11.920
(Applause)