WEBVTT

99:59:59.999 --> 99:59:59.999
So many of you have probably seen
the movie "The Martian."

99:59:59.999 --> 99:59:59.999
But for those of you who did not,
it's a movie about an astronaut

99:59:59.999 --> 99:59:59.999
who is stranded on Mars
and his efforts to stay alive

99:59:59.999 --> 99:59:59.999
until the Earth can send a rescue mission
to bring him back to Earth.

99:59:59.999 --> 99:59:59.999
Gladly, they do re-establish communication
with the character, astronaut Watney,

99:59:59.999 --> 99:59:59.999
at some point, so that he's not as alone
on Mars until he can be rescued.

99:59:59.999 --> 99:59:59.999
So while you're watching the movie,
and even if you haven't,

99:59:59.999 --> 99:59:59.999
when you think about Mars,
you're probably thinking about

99:59:59.999 --> 99:59:59.999
how far away it is and how distant.

99:59:59.999 --> 99:59:59.999
And, what might not
have occurred to you is,

99:59:59.999 --> 99:59:59.999
what are the logistics really like
of working on another planet?

99:59:59.999 --> 99:59:59.999
Of living on two planets when

99:59:59.999 --> 99:59:59.999
there are people on the Earth and
there are rovers or people on Mars?

99:59:59.999 --> 99:59:59.999
So think about when you have friends,
families and co-workers in California,

99:59:59.999 --> 99:59:59.999
on the West Coast
or in other parts of the world.

99:59:59.999 --> 99:59:59.999
When you're trying to communicate
with them, one of the things

99:59:59.999 --> 99:59:59.999
you probably first think about is --

99:59:59.999 --> 99:59:59.999
Wait, what time is it in California?

99:59:59.999 --> 99:59:59.999
Will I wake them up? Is it okay to call?

99:59:59.999 --> 99:59:59.999
So even if you're interacting
with colleagues who are in Europe,

99:59:59.999 --> 99:59:59.999
you're immediately thinking about,

99:59:59.999 --> 99:59:59.999
what does it take to coordinate
communication when people are far away?

99:59:59.999 --> 99:59:59.999
So we don't have people on Mars right now,
but we do have rovers.

99:59:59.999 --> 99:59:59.999
And actually right now, on Curiosity,
it is 6:10 in the morning on Mars.

99:59:59.999 --> 99:59:59.999
We have four rovers on Mars.
The United States has put four rovers

99:59:59.999 --> 99:59:59.999
on Mars since the mid-1990s,

99:59:59.999 --> 99:59:59.999
and I have been privileged enough
to work on three of them.

99:59:59.999 --> 99:59:59.999
So, I am a spacecraft engineer,
a spacecraft operations engineer,

99:59:59.999 --> 99:59:59.999
at NASA's Jet Propulsion Laboratory
in Los Angeles, California.

99:59:59.999 --> 99:59:59.999
And these rovers are robotic emissaries.

99:59:59.999 --> 99:59:59.999
So, they are our eyes and our ears
and they see the planet for us

99:59:59.999 --> 99:59:59.999
until we can send people.

99:59:59.999 --> 99:59:59.999
So we learn how to operate
on other planets through these rovers.

99:59:59.999 --> 99:59:59.999
So before we send people, we send robots.

99:59:59.999 --> 99:59:59.999
So the reason there's a time difference
on Mars right now,

99:59:59.999 --> 99:59:59.999
from the time that we're at

99:59:59.999 --> 99:59:59.999
is because the Martian day
is longer than the Earth day.

99:59:59.999 --> 99:59:59.999
Our Earth day is 24 hours because that's

99:59:59.999 --> 99:59:59.999
how long it takes the Earth to rotate,
how long it takes to go around once.

99:59:59.999 --> 99:59:59.999
So our day is 24 hours.

99:59:59.999 --> 99:59:59.999
It takes Mars 24 hours and
approximately 40 minutes to rotate once.

99:59:59.999 --> 99:59:59.999
So that means that the Martian day
is 40 minutes longer than the Earth day.

99:59:59.999 --> 99:59:59.999
So teams of people who are operating
the rovers on Mars, like this one,

99:59:59.999 --> 99:59:59.999
what we are doing is we are
living on Earth, but working on Mars.

99:59:59.999 --> 99:59:59.999
So we have to think as if we are actually
on Mars with the Rover.

99:59:59.999 --> 99:59:59.999
Our job, the job of this team,
of which I'm a part of

99:59:59.999 --> 99:59:59.999
is to send commands to the rover
to tell it what to do the next day.

99:59:59.999 --> 99:59:59.999
To tell it to drive or drill or
tell her whatever she's supposed to do.

99:59:59.999 --> 99:59:59.999
So while she's sleeping --
and the rover does sleep at night

99:59:59.999 --> 99:59:59.999
because she needs
to re-charge her batteries

99:59:59.999 --> 99:59:59.999
and she needs to weather
the cold Martian night.

99:59:59.999 --> 99:59:59.999
And so she sleeps.

99:59:59.999 --> 99:59:59.999
So while she sleeps, we work
on her program for the next day.

99:59:59.999 --> 99:59:59.999
So I work the Martian night shift.

99:59:59.999 --> 99:59:59.999
So in order to come to work on the Earth
at the same time every day on Mars --

99:59:59.999 --> 99:59:59.999
like, let's say I need to be
at work at 5:00 pm,

99:59:59.999 --> 99:59:59.999
this team needs to be at work
at 5:00 pm Mars time every day,

99:59:59.999 --> 99:59:59.999
then we have to come to work
on the Earth 40 minutes later every day,

99:59:59.999 --> 99:59:59.999
in order to stay in sync with Mars.

99:59:59.999 --> 99:59:59.999
That's like moving a time zone every day.

99:59:59.999 --> 99:59:59.999
So one day you come in at 8:00,
the next day 40 minutes later at 8:40,

99:59:59.999 --> 99:59:59.999
the next day 40 minutes later at 9:20,
the next day at 10:00,

99:59:59.999 --> 99:59:59.999
so you keep moving 40 minutes every day,


99:59:59.999 --> 99:59:59.999
until soon you're coming to work
in the middle of the night --

99:59:59.999 --> 99:59:59.999
the middle of the Earth night.

99:59:59.999 --> 99:59:59.999
Right? So you can imagine
how confusing that is.

99:59:59.999 --> 99:59:59.999
Hence, the Mars watch.

99:59:59.999 --> 99:59:59.999
This watch has been mechanically --

99:59:59.999 --> 99:59:59.999
the weights have been mechanically
adjusted so that it runs more slowly.

99:59:59.999 --> 99:59:59.999
When I got this watch in 2004

99:59:59.999 --> 99:59:59.999
with Spirit and Opportunity,
the rovers back then,

99:59:59.999 --> 99:59:59.999
we didn't start out thinking
that we were going to need Mars watches.

99:59:59.999 --> 99:59:59.999
Right? We thought, okay,
we'll just have the time on our computers

99:59:59.999 --> 99:59:59.999
and on the mission control screens
and that would be enough.

99:59:59.999 --> 99:59:59.999
Yeah, not so much.

99:59:59.999 --> 99:59:59.999
Because we weren't just
working on Mars time,

99:59:59.999 --> 99:59:59.999
we were actually living on Mars time.

99:59:59.999 --> 99:59:59.999
And we got just instantaneously confused
about what time it was.

99:59:59.999 --> 99:59:59.999
So you really needed something
on your wrist to tell you, alright,

99:59:59.999 --> 99:59:59.999
what time is it on the Earth,
what time is it on Mars.

99:59:59.999 --> 99:59:59.999
And it wasn't just the time on Mars
that was confusing,

99:59:59.999 --> 99:59:59.999
we also needed to be able
to talk to each other about it.

99:59:59.999 --> 99:59:59.999
So a "sol" is a Martian day --
again, 24 hours and 40 minutes.

99:59:59.999 --> 99:59:59.999
So when we're talking about something
that's happening on the earth,

99:59:59.999 --> 99:59:59.999
we will say, today.

99:59:59.999 --> 99:59:59.999
So, for Mars, we say, "tosol."

99:59:59.999 --> 99:59:59.999
Yesterday became 'yestersol' for Mars.

99:59:59.999 --> 99:59:59.999
Again, we didn't start out thinking,
"oh let's invent a language."

99:59:59.999 --> 99:59:59.999
It was just very confusing.

99:59:59.999 --> 99:59:59.999
I remember someone
walked up to me and said,

99:59:59.999 --> 99:59:59.999
"I would like to do this activity
on the vehicle tomorrow, on the rover."

99:59:59.999 --> 99:59:59.999
And I said, "tomorrow, tomorrow,
or Mars tomorrow?" Right?

99:59:59.999 --> 99:59:59.999
We started this terminology because
we needed a way to talk to each other.

99:59:59.999 --> 99:59:59.999
Tomorrow became "nextersol" or "solorrow"

99:59:59.999 --> 99:59:59.999
because people had different preferences
for the words they use.

99:59:59.999 --> 99:59:59.999
Some of you might say soda
and some of you might say pop.

99:59:59.999 --> 99:59:59.999
So we have people who say
nextersol or solorrow.

99:59:59.999 --> 99:59:59.999
And then something that I noticed after
a few years of working on these missions,

99:59:59.999 --> 99:59:59.999
was that the people who work
on the rovers, we say "tosol."

99:59:59.999 --> 99:59:59.999
The people who work on the
landing missions that don't rove around,

99:59:59.999 --> 99:59:59.999
they say "tosol."
[Different vowel sound]

99:59:59.999 --> 99:59:59.999
So I could actually tell what mission
you worked on from your Martian accent.

99:59:59.999 --> 99:59:59.999
[Laughter]

99:59:59.999 --> 99:59:59.999
So we have the watches and the language
and you're detecting a theme here, right?.

99:59:59.999 --> 99:59:59.999
So that we don't get confused.

99:59:59.999 --> 99:59:59.999
But even the Earth daylight
could confuse us.

99:59:59.999 --> 99:59:59.999
If you think that right now,
you've come to work

99:59:59.999 --> 99:59:59.999
and it's the middle of the Martian night
and there's light streaming in

99:59:59.999 --> 99:59:59.999
from the windows,
that's confusing as well.

99:59:59.999 --> 99:59:59.999
So you can see from
this image of the control room

99:59:59.999 --> 99:59:59.999
that all of the blinds are down.

99:59:59.999 --> 99:59:59.999
So that there's no light to distract us.

99:59:59.999 --> 99:59:59.999
The blinds went down all over the building
about a week before landing

99:59:59.999 --> 99:59:59.999
and they didn't go up
until we went off Mars time.

99:59:59.999 --> 99:59:59.999
So this also works
for the house, for at home.

99:59:59.999 --> 99:59:59.999
So I've been on Mars time three times,
and my husband is like, okay,

99:59:59.999 --> 99:59:59.999
we're getting ready for Mars time.

99:59:59.999 --> 99:59:59.999
And so he'll put foil all over the windows
and dark curtains and shades

99:59:59.999 --> 99:59:59.999
because it also affects your families.

99:59:59.999 --> 99:59:59.999
And so here I was living in kind of 
his darkened environment but so was he,

99:59:59.999 --> 99:59:59.999
and he'd gotten used to it,

99:59:59.999 --> 99:59:59.999
but then I would get these plaintive
emails from him when he was at work.

99:59:59.999 --> 99:59:59.999
Should I come home? Are you awake?
What time is it on Mars?

99:59:59.999 --> 99:59:59.999
And I decided, okay,
so he needs a Mars watch.

99:59:59.999 --> 99:59:59.999
[Laughter]

99:59:59.999 --> 99:59:59.999
But of course, it's 2016,
so there's an app for that.

99:59:59.999 --> 99:59:59.999
So now instead of the watches,
we can also use our phones.

99:59:59.999 --> 99:59:59.999
But the impact on families
was just across the board,

99:59:59.999 --> 99:59:59.999
it wasn't just those of us
who were working on the rovers

99:59:59.999 --> 99:59:59.999
but our families as well.

99:59:59.999 --> 99:59:59.999
This is David O,
one of our flight directors,

99:59:59.999 --> 99:59:59.999
and he's at the beach in Los Angeles
with his family at 1:00 in the morning.

99:59:59.999 --> 99:59:59.999
So because we landed in August

99:59:59.999 --> 99:59:59.999
and his kids didn't have to
go back to school until September,

99:59:59.999 --> 99:59:59.999
they actually went on to Mars time
with him for one month.

99:59:59.999 --> 99:59:59.999
They got up 40 minutes later every day

99:59:59.999 --> 99:59:59.999
and they were on dad's work schedule.

99:59:59.999 --> 99:59:59.999
So they lived on Mars time for a month
and had these great adventures,

99:59:59.999 --> 99:59:59.999
like going bowling
in the middle of the night

99:59:59.999 --> 99:59:59.999
or going to the beach.

99:59:59.999 --> 99:59:59.999
And one of the things
that we all discovered

99:59:59.999 --> 99:59:59.999
is that you can get
anywhere in Los Angeles

99:59:59.999 --> 99:59:59.999
at 3:00 in the morning
when there's no traffic.