0:00:01.054,0:00:04.603
So many of you have probably seen[br]the movie "The Martian."

0:00:05.141,0:00:08.958
But for those of you who did not,[br]it's a movie about an astronaut

0:00:08.982,0:00:13.525
who is stranded on Mars,[br]and his efforts to stay alive

0:00:13.549,0:00:18.045
until the Earth can send a rescue mission[br]to bring him back to Earth.

0:00:19.205,0:00:22.344
Gladly, they do re-establish communication

0:00:22.368,0:00:24.906
with the character,[br]astronaut Watney, at some point

0:00:24.930,0:00:30.201
so that he's not as alone[br]on Mars until he can be rescued.

0:00:30.726,0:00:33.488
So while you're watching the movie,[br]or even if you haven't,

0:00:33.512,0:00:35.060
when you think about Mars,

0:00:35.084,0:00:39.884
you're probably thinking about[br]how far away it is and how distant.

0:00:39.908,0:00:42.487
And, what might not[br]have occurred to you is,

0:00:42.511,0:00:46.408
what are the logistics really like[br]of working on another planet --

0:00:46.432,0:00:48.678
of living on two planets

0:00:48.702,0:00:54.536
when there are people on the Earth[br]and there are rovers or people on Mars?

0:00:54.560,0:00:58.718
So think about when you have friends,[br]families and co-workers

0:00:58.742,0:01:01.900
in California, on the West Coast[br]or in other parts of the world.

0:01:02.225,0:01:04.278
When you're trying[br]to communicate with them,

0:01:04.302,0:01:06.740
one of the things[br]you probably first think about is:

0:01:06.764,0:01:08.860
wait, what time is it in California?

0:01:08.884,0:01:11.479
Will I wake them up? Is it OK to call?

0:01:11.883,0:01:15.234
So even if you're interacting[br]with colleagues who are in Europe,

0:01:15.258,0:01:17.300
you're immediately thinking about:

0:01:17.324,0:01:24.324
What does it take to coordinate[br]communication when people are far away?

0:01:24.973,0:01:30.557
So we don't have people on Mars[br]right now, but we do have rovers.

0:01:30.581,0:01:35.686
And actually right now, on Curiosity,[br]it is 6:10 in the morning.

0:01:35.710,0:01:38.481
So, 6:10 in the morning on Mars.

0:01:38.876,0:01:40.877
We have four rovers on Mars.

0:01:40.901,0:01:44.908
The United States has put four rovers[br]on Mars since the mid-1990s,

0:01:44.932,0:01:48.871
and I have been privileged enough[br]to work on three of them.

0:01:48.895,0:01:53.416
So, I am a spacecraft engineer,[br]a spacecraft operations engineer,

0:01:53.440,0:01:58.287
at NASA's Jet Propulsion Laboratory[br]in Los Angeles, California.

0:01:58.856,0:02:03.017
And these rovers[br]are our robotic emissaries.

0:02:03.041,0:02:09.319
So, they are our eyes and our ears,[br]and they see the planet for us

0:02:09.343,0:02:11.176
until we can send people.

0:02:11.200,0:02:16.493
So we learn how to operate[br]on other planets through these rovers.

0:02:16.517,0:02:20.823
So before we send people, we send robots.

0:02:21.326,0:02:25.277
So the reason there's a time difference[br]on Mars right now,

0:02:25.301,0:02:26.603
from the time that we're at

0:02:26.627,0:02:30.601
is because the Martian day[br]is longer than the Earth day.

0:02:30.954,0:02:33.751
Our Earth day is 24 hours,

0:02:33.775,0:02:37.149
because that's how long it takes[br]the Earth to rotate,

0:02:37.173,0:02:39.174
how long it takes to go around once.

0:02:39.198,0:02:41.110
So our day is 24 hours.

0:02:41.486,0:02:48.306
It takes Mars 24 hours and approximately[br]40 minutes to rotate once.

0:02:48.330,0:02:54.748
So that means that the Martian day[br]is 40 minutes longer than the Earth day.

0:02:55.207,0:03:00.362
So teams of people who are operating[br]the rovers on Mars, like this one,

0:03:00.386,0:03:05.798
what we are doing is we are living[br]on Earth, but working on Mars.

0:03:05.822,0:03:11.287
So we have to think as if we are actually[br]on Mars with the rover.

0:03:11.654,0:03:15.233
Our job, the job of this team,[br]of which I'm a part of,

0:03:15.257,0:03:21.186
is to send commands to the rover[br]to tell it what to do the next day.

0:03:21.210,0:03:25.239
To tell it to drive or drill[br]or tell her whatever she's supposed to do.

0:03:25.553,0:03:30.019
So while she's sleeping --[br]and the rover does sleep at night

0:03:30.043,0:03:32.413
because she needs[br]to recharge her batteries

0:03:32.437,0:03:36.333
and she needs to weather[br]the cold Martian night.

0:03:36.357,0:03:37.719
And so she sleeps.

0:03:37.743,0:03:42.511
So while she sleeps, we work[br]on her program for the next day.

0:03:42.857,0:03:45.839
So I work the Martian night shift.

0:03:45.863,0:03:47.454
(Laughter)

0:03:47.478,0:03:54.106
So in order to come to work on the Earth[br]at the same time every day on Mars --

0:03:54.130,0:03:56.534
like, let's say I need to be[br]at work at 5:00 p.m.,

0:03:56.558,0:04:02.127
this team needs to be at work[br]at 5:00 p.m. Mars time every day,

0:04:02.151,0:04:09.151
then we have to come to work[br]on the Earth 40 minutes later every day,

0:04:10.142,0:04:12.321
in order to stay in sync with Mars.

0:04:12.345,0:04:15.297
That's like moving a time zone every day.

0:04:15.321,0:04:20.776
So one day you come in at 8:00,[br]the next day 40 minutes later at 8:40,

0:04:20.800,0:04:24.069
the next day 40 minutes later at 9:20,

0:04:24.093,0:04:25.682
the next day at 10:00.

0:04:25.706,0:04:29.284
So you keep moving 40 minutes every day,

0:04:29.308,0:04:32.297
until soon you're coming to work[br]in the middle of the night --

0:04:32.321,0:04:34.138
the middle of the Earth night.

0:04:34.162,0:04:37.780
Right? So you can imagine[br]how confusing that is.

0:04:37.804,0:04:39.956
Hence, the Mars watch.

0:04:39.980,0:04:40.981
(Laughter)

0:04:41.005,0:04:44.523
This weights in this watch[br]have been mechanically adjusted

0:04:44.547,0:04:47.075
so that it runs more slowly.

0:04:47.099,0:04:48.988
Right? And we didn't start out --

0:04:49.012,0:04:51.238
I got this watch in 2004

0:04:51.262,0:04:54.566
when Spirit and Opportunity,[br]the rovers back then.

0:04:54.590,0:04:56.196
We didn't start out thinking

0:04:56.220,0:04:58.651
that we were going to need Mars watches.

0:04:58.675,0:05:03.106
Right? We thought, OK,[br]we'll just have the time on our computers

0:05:03.130,0:05:06.778
and on the mission control screens,[br]and that would be enough.

0:05:06.802,0:05:08.183
Yeah, not so much.

0:05:08.207,0:05:11.056
Because we weren't just[br]working on Mars time,

0:05:11.080,0:05:14.239
we were actually living on Mars time.

0:05:14.263,0:05:18.546
And we got just instantaneously confused[br]about what time it was.

0:05:18.570,0:05:22.363
So you really needed something[br]on your wrist to tell you:

0:05:22.387,0:05:25.678
What time is it on the Earth?[br]What time is it on Mars?

0:05:26.107,0:05:32.001
And it wasn't just the time on Mars[br]that was confusing;

0:05:32.025,0:05:36.794
we also needed to be able[br]to talk to each other about it.

0:05:37.337,0:05:42.964
So a "sol" is a Martian day --[br]again, 24 hours and 40 minutes.

0:05:42.988,0:05:46.183
So when we're talking about something[br]that's happening on the Earth,

0:05:46.207,0:05:47.516
we will say, today.

0:05:48.228,0:05:51.060
So, for Mars, we say, "tosol."

0:05:51.084,0:05:52.922
(Laughter)

0:05:53.992,0:05:58.509
Yesterday became "yestersol" for Mars.

0:05:58.837,0:06:03.344
Again, we didn't start out thinking,[br]"Oh, let's invent a language."

0:06:03.368,0:06:04.658
It was just very confusing.

0:06:04.682,0:06:06.863
I remember somebody[br]walked up to me and said,

0:06:06.887,0:06:10.320
"I would like to do this activity[br]on the vehicle tomorrow, on the rover."

0:06:10.344,0:06:15.455
And I said, "Tomorrow, tomorrow,[br]or Mars, tomorrow?"

0:06:15.987,0:06:21.039
We started this terminology because[br]we needed a way to talk to each other.

0:06:21.063,0:06:22.191
(Laughter)

0:06:22.215,0:06:26.491
Tomorrow became "nextersol" or "solorrow."

0:06:27.216,0:06:30.831
Because people have different preferences[br]for the words they use.

0:06:30.855,0:06:34.231
Some of you might say "soda"[br]and some of you might say "pop."

0:06:34.829,0:06:38.035
So we have people who say[br]"nextersol" or "solorrow."

0:06:38.562,0:06:43.286
And then something that I noticed after[br]a few years of working on these missions,

0:06:43.310,0:06:47.962
was that the people who work[br]on the rovers, we say "tosol."

0:06:48.426,0:06:51.960
The people who work on the[br]landed missions that don't rove around,

0:06:51.984,0:06:53.456
they say "tosoul."

0:06:53.958,0:06:58.677
So I could actually tell what mission[br]you worked on from your Martian accent.

0:06:58.701,0:07:01.951
(Laughter)

0:07:01.975,0:07:05.835
So we have the watches and the language,[br]and you're detecting a theme here, right?

0:07:05.859,0:07:07.855
So that we don't get confused.

0:07:08.419,0:07:12.226
But even the Earth daylight[br]could confuse us.

0:07:12.669,0:07:15.008
If you think that right now,[br]you've come to work

0:07:15.032,0:07:17.127
and it's the middle of the Martian night

0:07:17.151,0:07:20.449
and there's light streaming in[br]from the windows

0:07:20.473,0:07:22.621
that's going to be confusing as well.

0:07:23.081,0:07:25.586
So you can see from[br]this image of the control room

0:07:25.610,0:07:27.879
that all of the blinds are down.

0:07:27.903,0:07:30.906
So that there's no light to distract us.

0:07:30.930,0:07:35.282
The blinds went down all over the building[br]about a week before landing,

0:07:35.306,0:07:38.573
and they didn't go up[br]until we went off Mars time.

0:07:39.027,0:07:42.208
So this also works[br]for the house, for at home.

0:07:42.232,0:07:45.005
I've been on Mars time three times,[br]and my husband is like,

0:07:45.029,0:07:46.844
OK, we're getting ready for Mars time.

0:07:46.868,0:07:53.070
And so he'll put foil all over the windows[br]and dark curtains and shades

0:07:53.094,0:07:56.241
because it also affects your families.

0:07:56.265,0:08:01.144
And so here I was living in kind of[br]this darkened environment, but so was he.

0:08:01.705,0:08:03.001
And he'd gotten used to it.

0:08:03.025,0:08:06.667
But then I would get these plaintive[br]emails from him when he was at work.

0:08:07.257,0:08:10.549
Should I come home? Are you awake?

0:08:10.573,0:08:13.703
What time is it on Mars?

0:08:13.727,0:08:16.225
And I decided, OK,[br]so he needs a Mars watch.

0:08:16.249,0:08:17.784
(Laughter)

0:08:17.808,0:08:22.242
But of course, it's 2016,[br]so there's an app for that.

0:08:22.266,0:08:23.544
(Laughter)

0:08:23.568,0:08:28.182
So now instead of the watches,[br]we can also use our phones.

0:08:28.600,0:08:32.740
But the impact on families[br]was just across the board;

0:08:32.764,0:08:36.426
it wasn't just those of us[br]who were working on the rovers

0:08:36.450,0:08:38.664
but our families as well.

0:08:38.688,0:08:41.167
This is David Oh,[br]one of our flight directors,

0:08:41.191,0:08:45.665
and he's at the beach in Los Angeles[br]with his family at 1:00 in the morning.

0:08:45.689,0:08:47.112
(Laughter)

0:08:47.136,0:08:50.116
So because we landed in August

0:08:50.140,0:08:54.586
and his kids didn't have to go back[br]to school until September,

0:08:54.610,0:08:59.358
they actually went on to Mars time[br]with him for one month.

0:08:59.382,0:09:04.151
They got up 40 minutes later every day.

0:09:04.175,0:09:06.358
And they were on dad's work schedule.

0:09:06.382,0:09:10.357
So they lived on Mars time for a month[br]and had these great adventures,

0:09:10.381,0:09:12.478
like going bowling[br]in the middle of the night

0:09:12.502,0:09:13.820
or going to the beach.

0:09:14.149,0:09:17.508
And one of the things[br]that we all discovered

0:09:17.532,0:09:21.520
is you can get anywhere in Los Angeles

0:09:21.544,0:09:25.097
at 3:00 in the morning[br]when there's no traffic.

0:09:25.121,0:09:26.595
(Laughter)

0:09:26.619,0:09:27.811
So we would get off work,

0:09:27.835,0:09:30.950
and we didn't want to go home[br]and bother our families,

0:09:30.974,0:09:34.164
and we were hungry, so instead of[br]going locally to eat something,

0:09:34.188,0:09:37.752
we'd go, "Wait, there's this great[br]all-night deli in Long Beach,

0:09:37.776,0:09:40.018
and we can get there in 10 minutes!"

0:09:40.042,0:09:42.763
So we would drive down --[br]it was like the 60s, no traffic.

0:09:42.787,0:09:46.542
We would drive down there,[br]and the restaurant owners would go,

0:09:46.566,0:09:48.728
"Who are you people?

0:09:49.421,0:09:53.594
And why are you at my restaurant[br]at 3:00 in the morning?"

0:09:53.958,0:09:58.848
So they came to realize[br]that there were these packs of Martians,

0:09:59.661,0:10:04.326
roaming the LA freeways,[br]in the middle of the night --

0:10:05.288,0:10:07.311
in the middle of the Earth night.

0:10:07.335,0:10:12.132
And we did actually[br]start calling ourselves Martians.

0:10:12.581,0:10:18.187
So those of us who were on Mars time[br]would refer to ourselves as Martians,

0:10:18.211,0:10:21.064
and everyone else as Earthlings.

0:10:21.088,0:10:22.388
(Laughter)

0:10:22.412,0:10:28.107
And that's because when you're moving[br]a time-zone every day,

0:10:28.131,0:10:33.944
you start to really feel separated[br]from everyone else.

0:10:33.968,0:10:37.887
You're literally in your own world.

0:10:38.704,0:10:45.629
So I have this button on that says,[br]"I survived Mars time. Sol 0-90."

0:10:45.653,0:10:48.398
And there's a picture of it[br]up on the screen.

0:10:48.422,0:10:54.051
So the reason we got these buttons[br]is because we work on Mars time

0:10:54.075,0:10:59.124
in order to be as efficient as possible[br]with the rover on Mars,

0:10:59.148,0:11:01.438
to make the best use of our time.

0:11:01.462,0:11:05.348
But we don't stay on Mars time[br]for more than three to four months.

0:11:05.372,0:11:09.640
Eventually, we'll move to a modified Mars[br]time, which is what we're working now.

0:11:10.379,0:11:15.036
And that's because it's hard on[br]your bodies, it's hard on your families.

0:11:15.060,0:11:19.942
In fact, there were sleep researchers[br]who actually were studying us

0:11:19.966,0:11:25.003
because it was so unusual for humans[br]to try to extend their day.

0:11:25.327,0:11:26.617
And they had about 30 of us

0:11:26.641,0:11:30.267
that they would do[br]sleep deprivation experiments on.

0:11:30.291,0:11:33.854
So I would come in and take the test[br]and I fell asleep in each one.

0:11:33.878,0:11:40.520
And that was because, again,[br]this eventually becomes hard on your body.

0:11:40.544,0:11:43.859
Even though it was a blast.

0:11:43.883,0:11:48.397
It was a huge bonding experience[br]with the other members on the team,

0:11:48.421,0:11:51.261
but it is difficult to sustain.

0:11:52.243,0:11:58.428
So these rover missions are our first[br]steps out into the solar system.

0:11:58.452,0:12:03.525
We are learning how to live[br]on more than one planet.

0:12:03.549,0:12:08.625
We are changing our perspective[br]to become multi-planetary.

0:12:08.943,0:12:11.738
So the next time you see[br]a Star Wars movie,

0:12:11.762,0:12:15.437
and there are people going[br]from the Dagobah system to Tatooine,

0:12:15.461,0:12:20.951
think about what it really means to have[br]people spread out so far.

0:12:20.975,0:12:24.037
What it means in terms[br]of the distances between them,

0:12:24.061,0:12:27.881
how they will start to feel[br]separate from each other

0:12:27.905,0:12:31.129
and just the logistics of the time.

0:12:31.937,0:12:36.489
We have not sent people[br]to Mars yet, but we hope to.

0:12:36.513,0:12:40.352
And between companies like SpaceX and NASA

0:12:40.376,0:12:43.865
and all of the international[br]space agencies of the world,

0:12:43.889,0:12:47.656
we hope to do that[br]in the next few decades.

0:12:47.680,0:12:53.505
So soon we will have people on Mars,[br]and we truly will be multi-planetary.

0:12:54.000,0:12:56.412
And the young boy or the young girl

0:12:56.436,0:13:03.436
who will be going to Mars could be[br]in this audience or listening today.

0:13:04.201,0:13:09.803
I have wanted to work at JPL[br]on these missions since I was 14 years old

0:13:09.827,0:13:12.049
and I am privileged to be a part of it.

0:13:12.073,0:13:16.127
And this is a remarkable time[br]in the space program,

0:13:16.151,0:13:19.325
and we are all in this journey together.

0:13:19.349,0:13:24.560
So the next time you think[br]you don't have enough time in your day,

0:13:24.584,0:13:29.362
just remember, it's all a matter[br]of your Earthly perspective.

0:13:29.386,0:13:30.537
Thank you.

0:13:30.561,0:13:34.675
(Applause)