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♪Music♪

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Narrator: The universe. For all we have

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learned about it, we have still only scratched the surface.

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Everything that we can see around us makes up less than

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5 percent of what's actually out there.

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All the rest is called dark matter and dark energy. What are they?

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We still don't know, even thought they determine the fate

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of the universe. We have confirmed over

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3.000 planets orbiting stars other than the sun. but most of these

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extrasolar planets are huge, and very close to their host

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star. How common are planetary arrangements like our own?

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And how many planets in our galaxy have the potential to harbor life?

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These fundamental questions are

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part of what drives NASA science, and they spur the development

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of new space observatories. WFIRST,

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the Wide Field Infrared Survey Telescope, is one of these.

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WFIRST is built on an existing telescope

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that is very similar to Hubble, but with the added benefit of

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25 years of technological development. Each of the

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Wide Field Instrument's images will have the depth and clarity of Hubble,

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but cover a sky area 100 times larger.

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That's thanks to an arrangement of 18 sensors in the camera to

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Hubble's one. Viewing the sky in infrared wavelengths

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allows astronomers to see relatively cool objects,

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like interstellar gas, dust and exoplanets,

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as well as stars.

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WFIRSt will lead the push to understand

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dark energy, a mysterious pressure that is making

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the universe expand ever faster. Dark energy makes

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up 68 percent of the cosmos, and its properties--

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whatever they are--determine the fate of the universe.

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But no one knows what it is, or exactly how it behaves.

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Another mysterious component of the

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universe WFIRST will study is dark matter. Dark matter

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accounts for 27 percent of the cosmos--5 times

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as much as the matter we can see--but has remained invisible to us.

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We can detect it by seeing how its gravity warps

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light from distant galaxies, a process called

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gravitational lensing. WFIRST's powerful

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2.4 meter telescope will also help us in the search for

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extrasolar planets, or exoplanets. Using the

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same gravitational lensing principles, WFIRST will

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watch for so-called 'gravitational microlensing events',

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a unique light signature caused when a planet and its host star

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pass in front of a background star. This technique

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extends planet-detection capabilities to smaller and more distant

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worlds than other methods, so it can catch ones that have

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eluded us before. WFIRST's enormous field

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of view will allow scientists to watch huge portions

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of the Milky Way for these microlensing events. As a result,

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they will be able to complete the census of exoplanets

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begun by Kepler. To deepen its study

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of exoplanets, WFIRST will also be outfitted a

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beyond state-of-the-art coronagraph. The coronagraph works

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by masking star light to reveal the faint light reflected by any

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potential planets. WFIRST's coronagraph

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will directly image and analyze Neptune-size planets

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in orbits slightly greater than Earth's. Existing coronagraphs

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can only image larger planets that are much more distant

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form their host stars, so this new capability

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represents a dramatic improvement. in order to make

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all these measurements, WFIRST will move to nearly

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1 million miles from Earth and orbit a special area of space

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called a Lagrange point. This particular point,

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called Earth-Sun L2, is one of several locations

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where the combined gravitational effects of the Sun and Earth, create a

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zone of stability where a spacecraft can pace Earth as it orbits.

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WFIRST will be a way to answer many

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of the biggest questions about the universe. Questions like

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"how does the universe work?" and "are we alone?"

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Its wide-field view and coronagraph will compliment

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missions like the James Webb Space Telescope and the

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Transiting Exoplanet Survey Satellite, TESS.

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WFIRST will be an indispensable part of space science

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during the next decade and beyond.

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[Beeping]

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[Beeping]

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[Beeping]