[Music]
>>air-LUSI stands for the Airborne Lunar Spectral
Irradiance mission.
What we're measuring is the amount of light
at various wavelengths that are being reflected
off the Moon.
We want to know this because we essentially
are using the Moon as a benchmark so that
Earth-observing satellites can turn and look
at the moon and set the scale on the amount
of light they're measuring from the Earth.
So it's kind of an indirect way of actually
improving our understanding of the Earth.
[Music/Background noise]
>>Both computers are up and running.
Artemis has giving us a power-on.
Ok, so now we're going to start logging data.
So it's sending code to Artemis.
>>So we've set it up here, even before we put
it in the plane.
We have a system that simulates it being in
the airplane, so that we can test it all out.
In the distance you can see a disc of light.
That's our Moon simulator that we use to calibrate
the telescope.
>>We measure the Moon's brightness by using
a spectrometer, which is actually taking light
from a telescope that is pointed at the Moon.
What typically becomes a problem is that you
have to contend with the atmosphere.
The atmosphere actually affects your measurement
greatly.
And so we have to actually put that type of
instrumentation on the ER-2, which flies up
to 70,000 feet, and gives us a viewpoint of
the Moon above 90% of the atmosphere, almost
the same view of the Moon as Earth-Orbiting
satellites would have.
[Music]
[ER-2 taking off]
>>Ok-
>>it's showtime.
>>in a minute, he'll flip the switch.
>>Earth-observing satellites, we try and calibrate
them before they go up, but the calibration
always changes; they slowly degrade being
in the space environment, and they currently
use the Moon to trend that degradation, but
if we could put a good absolute calibration
on the Moon, that would allow them to do an
improvement on their current calibration scheme
and would also allow them to inter-compare
well.
[Music/background noise]
>>Ok, success!
>>So there are a lot of benefits to having all
the earth observing satellites have this common
calibration source.
>>Every instrument that's been launched into
space that looks at the Moon can benefit from
this because knowing what the Moon is, since
the Moon doesn't change, helps us both in
the future and retrospectively, and then we
get much more consistent time series of the Earth.
[ER-2 landing]
