Air LUCI is something that actually helps
not just a handful but all
Earth-observing satellites that can use
the Moon as a calibration reference.
And this actually greatly can enhance the
capacity for actually making accurate
measurements of the Earth.
Well, for one thing, it does give us the
opportunity to make those
improvements to our ability
to observe the Earth.
It's also something that hasn't been done
before at this level of accuracy.
So this is the most accurate measurements
that have ever been made of moonlight.
And moreover, up until our ability to do
this, we really have not
been able to predict accurately
the amount of light coming off the moon
at any given time within several percent.
Our measurements are down less than a 1%
accuracy, probably down
to maybe as far as a half a
percent accuracy.
So essentially, Air Lucy allows us to use
the Moon as a benchmark,
which allows sound lights to make sure
their measurements are accurate.
They can turn and look at the Moon and
make sure that what they read from that,
which is well known, will then reflect in
terms of the accuracy of
what they measure from Earth.
Basically, measure the amount of light
that's coming at different wavelengths,
which is pack full of information about
the surface of our Earth.
So, Air Lucy will help facilitate making
more accurate
measurements using the moon.
The moon is a pretty much perpetual
reference that doesn't
change past, present or future.
Any measurements that are made by
satellites in the past or
ones made in the future can
be inter-consistent over time.
That means if they're consistent over
time, we can do long-term
measurements of the Earth
that are consistent and
don't have spurious trends.
So those measurements actually now become
a very good
representation of changes in climate
and our Earth system.
The Euro 2 is an excellent aircraft for
this particular exercise, in particular
because it can fly
above 95% of the atmosphere.
That gives us basically a view of the
Moon that is very similar to what
satellites see from orbit.
And we don't have to worry about as much
the effects of the
atmosphere and our measurements.
Previous measurements that have been made
of the Moon to date have been done from
the surface of the Earth,
more recently from mountaintops.
But you still have a lot
of atmosphere to go through.
Air Lucy on the Euro 2 gives us an
opportunity to be near space.
Aerolucie is kind of non-intuitive in the
sense that it actually helps build our
capacity to measure how the earth is
changing and how those processes are
actually going on a global scale.
So if we better understand how climate is
changing, if we better understand how
systems interact with each other in terms
of weather, ocean currents, ecologies and
any type of process on the surface of the
earth, these lead to things that affect
humans on a daily basis.
We are affected by weather. We want more
accurate predictions of weather and how
weather may be changing with climate. We
want to know how this might be affecting
agriculture, forest
ecology, ocean ecology.
And if we can make better accurate and
more stable measurements from space, then
Aerolucie is actually contributing to a
lot, indirectly, to
people's everyday lives.
So interestingly enough what's really
beneficial about Erlucie is we're kind of
pulling together existing technologies
such as the ER2 and you know NIST
spectrometers and all those equipment
that is very very well understood and
and well known and bringing it to bear
and this sense we're doing something
new and innovative because we haven't
made this accurate a measurement of the
moon before. I would mention that you
know we're using the best you know
spectrometers from instrument systems
these have been vetted by the National
Institute of Standards and Technology.
We're using National Institute of
Standards and Technology sources so we're
basically making everything
internationally traceable in terms of
making very accurate
measurements but the beauty about what
we're doing is we're taking the best of
our existing technology and bringing it
to bear to make this special measurement.
Oh, I mean, the applications are great.
It helps us learn more about the climate.
It gets used to calibrate satellites
that are looking at climate,
and it's really fun to
come out here to NASA,
fly on this beautiful plane.
So it's been a fun project that way too.
Air Lucy's a telescope
attached to a spectrograph.
So the telescope collects the light,
and then the spectrograph
splits it into different colors
or wavelengths of light.
And then we can calibrate that instrument
so that we know the
amount of light very precisely.
And the idea is then to
fly that in an airplane,
have it point at the moon,
and measure the light
from the moon very precisely.
So the data we collect primarily impacts
the ability for the satellites that are
looking at the Earth to make high-quality
measurements that are used from
everything from weather to
climate change measurements.
And really being able to improve those,
you know, billion-dollar instruments with
a relatively inexpensive measurement so
that they can make climate quality
measurements is really exciting.
Yeah, so it's these measurements are used
to help calibrate the instruments that
are making the
measurements of the earth and climate.
So those instruments spend most of their
time looking at the light reflected off
the earth, but to calibrate them we want
them to turn and look at the moon.
So if we can measure the moon precisely,
then they can get a good calibration off
the moon and go back to looking at the
earth and make great measurements.
Oh boy, it's, so usually we do this kind
of work in a very
controlled laboratory environment.
And to come in here to an aircraft hangar
and make a high quality
calibration measurement,
you know, you can see the lights coming
in, the temperature is not controlled.
So that's a real challenge for us.
And then of course the instrument itself
is going to fly up at 70,000 feet.
It's minus 40 or 60
degrees Celsius up there.
So designing the instrument so it can
operate in that environment has also been
a real challenge for us.
The idea is, so this, our telescope
usually looks at the moon, so we make a
light source that
kind of mimics the moon,
and then we brought some instrumentation
that can measure the light coming from
that source very precisely,
and then the telescope's
going to look at that source.
And that's kind of how we
say, "transfer the calibration."
So we have our
well-calibrated instrumentation.
It looks at the source.
Our telescope looks at the source, and we
can take our
well-calibrated instrumentation
and kind of transfer that level of
accuracy to the telescope instrument.
So the ER-2 is a high-altitude aircraft.
It'll fly up above 65,000 feet.
And one of the challenges
of making these measurements,
like we, you know,
everyone can see the moon,
why not measure it
from down here on Earth?
And the reason is that the atmosphere
scatters some of the
light coming from the moon
before it gets down here to the Earth.
And figuring out how
much light you've lost
on that path is hard.
So that kind of degrades our ability
to measure from down here.
Putting it on this plane,
we're flying above 95%
of the Earth's atmosphere.
So it's much less scattering.
That little bit
that's left is the accuracy
which we can estimate that is good enough
to make our measurements.
So yeah, getting above the atmosphere
is a real important thing for us.
And the satellites are of course
above all of the atmosphere.
So we want to know the amount of light
that's up at the top of the atmosphere,
not what we're getting down here.
So the instrument itself needs to,
like we can't communicate directly with
it during the flight.
It's operated by the
pilot and he's just got
a few on-off switches that he can push
to operate the instrument.
He's busy, you know,
mostly busy flying the plane.
He can't do a whole lot.
So he had to program the instrument
so that the pilot just
right before takeoff,
he pushes one switch to
let the instrument know
we're taking off.
When he gets to altitude,
he pushes another switch
that deploys the telescope.
Then it automatically finds the moon
and stays tracked on the
moon while we collect the data.
Then after about 20
minutes, we've got enough data.
He pushes another switch to
tell it, you know, to shut down.
So it's all operated
on just a few switches
and a lot of good
programming from our computer guy.
So the interesting thing about the Moon
is its reflectance is very constant.
So you look up, you know, any night in
the sky, the amount of
light is changing all the time.
But its reflective properties, it's just
reflecting sunlight off its
surface and we're seeing that.
That reflectance is very constant.
So if we can make a few really good
measurements and then make a
model using the reflectance,
then you can use that model to predict at
any time where you are knowing where you
are and the Moon is and the Sun is,
how much light you would see.
So, it's really more
on the calibration side.
We've used, and it's some stuff we've
been doing at NIST over
the last, say, 20 years,
using tunable lasers to calibrate the
spectrograph and developing techniques
to get the spectrograph calibrated well
that have really been key
to making a high-quality measurement.
Yeah, so right now the way satellites try
to maintain their calibration is to bring
up a solar reflector of their own.
So they bring up kind of a white plaque
that the satellite can put in front and
bounce some sunlight off
of to do the calibration.
That takes up space, it takes up mass,
it's not the most
expensive part of the satellite.
But particularly as people are going
towards smaller satellites and CubeSats
and stuff like that,
having something like that on board is
way too much for them.
So if they could just turn and look at
the moon instead of having to carry up
some equipment of their own
to maintain their calibration,
that would be a big advance for those.
Then you could have smaller, more
cost-effective satellites in the future.
The challenges are...
So another thing that usually doesn't
happen back in the lab is no one says,
"Okay, at 102, you need to start your
calibration and be done in an hour."
But here, the plane's just been fueled,
we've turned on the
instrument, it's warming up.
In about 15 minutes, we need to start
calibrating, and it needs
to be finished an hour later,
and then they tow the plane out.
Something goes wrong, then
the whole schedule goes off.
So doing this all on schedule is another
challenge for us, and
makes things really exciting.
We're just hoping for some good weather
and some good luck and really looking
forward to being up in the air.