WEBVTT
Kind: captions
Language: en

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The data from the Landsat Data
Continuity Mission will be

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the best data that have ever been
collected from a Landsat satellite.

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With the increasing population,
our land use are changing

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at rates unprecedented
in human history.

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To manage and cope with these changes,
we need to have the observations,

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the information, the data that allow us
to understand what’s going on

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on the surface of the Earth
where most of us live.

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- Landsat’s been monitoring
the surface of the Earth since 1972,

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tracking resources like farms,
forests, and water and

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checking every continent,
every season, every year.

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- Well, we don’t call it the Data
Continuity Mission for nothing.

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- The continuity of those observations
is a really critical part of the ability

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to do the science we do
on how climate change and

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how land use are
transforming our planet.

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The Landsat program and the duration
of the Landsat time series is the

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only record we have of these
fundamental changes in land cover,

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including melting glaciers, including loss
of tropical forests, including the

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transformation from small-scale family
agriculture to large agribusiness.

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- After launch, LDCM will become
known as Landsat 8 since it’s

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the eighth in the Landsat program,
a partnership between NASA

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and the U.S. Geological Survey.
NASA is responsible for building

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and launching the satellite,
and the Geological Survey

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is in charge of operations and
receiving and archiving the data.

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LDCM carries two instruments,
each covering a different part

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of the
electromagnetic spectrum.

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- The OLI instrument monitors the
Earth’s surface in spectral wavelengths

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that you and I can see in – that’s the
visible wavelengths, and also in –

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just into the infrared regions – the near
infrared and shortwave infrared regions.

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- The Operational Land Imager
is used to track urban sprawl,

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forest loss and regrowth, changes in
farmland, and the melting of glaciers.

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- The Thermal Infrared Sensor
instrument – TIRS – monitors the

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Earth in thermal bands, which are –
it actually images temperature

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on the Earth’s surface.
- With TIRS, scientists are able to

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track how much water is used by
crops on individual farm fields.

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And the new technology used in
LDCM means that both TIRS and

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OLI will be much more sensitive
than previous Landsat sensors.

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- The greatest improvement we’ve
made in the LDCM satellite is that

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the sensors are what’s called
push broom sensors and

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not what was called
whisk broom sensors.

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Push broom sensors have thousands
of detectors that just image the Earth

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as the satellite passes over
the surface of the Earth.

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The older Landsat satellites –
Landsat 7, Landsat 5 –

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use a whisk broom technology,
which is many fewer detectors

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scanning back and forth
with a mechanical scanner.

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- The advantage of the push broom
is each detector has a longer time

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to dwell on each picture element,
or pixel, on the surface of the Earth.

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As a consequence, it creates a
sensor with a much higher sensitivity,

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expressed as
signal-to-noise ratio.

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- T minus 5, 4, 3, 2, 1,
and lift-off.

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[Music]

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- The LDCM observatory launches
out of the Vandenberg Air Force Base

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in California and launches
into what’s called a polar orbit.

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And so it orbits over the north
and south poles, taking imagery

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on the sunlit side of the
Earth every time it passes.

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- It takes about 100 minutes
to loop around the poles.

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LDCM will make 14 orbits each day and
cover the whole globe every 16 days.

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Every time they pass over the U.S.,
Landsat satellites beam data to the

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USGS Earth Resources Observation
and Science Center, or EROS,

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in South Dakota, one of several
receiving stations around the world.

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- This center operates the Landsat
archive that contains all of the

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U.S.-held data from
all of the Landsat satellites,

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and the LDCM data will
become part of that archive.

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- All of the data in the
Landsat archive at EROS

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can be obtained by anyone at no cost.
This freely available data has led to

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an incredible blossoming of
science research and applications.

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- My favorite part of the Landsat
program is the opportunity to think big.

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With free and open access to data
around the world, we’re not limited,

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as we once were, in our ability to
conceive of and analyze large data sets

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to look at really large-scale changes
over continents, over the globe.

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[Music]

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[Beeping and background music]

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[Music]