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Observatories like the Webb and Hubble space telescopes

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are transforming our 
understanding of the universe.

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They have revealed
that black holes are common,

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helped measure
the age of the cosmos,  

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and even played a key role
in one of astronomy's

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greatest surprises:
the discovery that the  

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universe’s expansion is accelerating,

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driven by an unknown force
we simply call “Dark Energy.”

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But some of the biggest questions 
in science remain unanswered. 

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What actually IS dark energy? 
What is dark matter?

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How common are
planetary systems like our own?

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And how did the universe evolve  

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from the first isolated galaxies 
into the cosmic web we see today? 

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NASA's Nancy Grace
Roman Space Telescope

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is designed to help
answer those questions. 

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Roman will carry a mirror the same 
size as Hubble's, 2.4 meters across,  

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but its true power comes
from something entirely different:

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Its Wide Field Instrument will allow  

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Roman to see enormous
portions of the sky at once.

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A single Roman
image will capture an  

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area a hundred times larger than Hubble’s or Webb’s infrared views,

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while still delivering high-resolution
and sensitive observations.

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Roman does this with
a unique array of 18 4k detectors. 

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They are arranged in
an arc to make full use

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of the optical system’s region
of best image quality. 

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Combined, they form
a 300 megapixel image. 

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That combination of power and 
scale changes what is possible. 

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Instead of studying
a few objects at a time,

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Roman will survey vast regions
of the universe.

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During its first five years,

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it is expected to observe
more than a billion galaxies

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and collect data that would take centuries

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for other observatories to gather.

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One of Roman's primary goals 
is investigating dark energy. 

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More than a century ago,
Albert Einstein's equations

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suggested the universe should
either expand or contract.

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In 1929, Edwin Hubble confirmed that galaxies are moving  

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away from one another, showing 
that the universe is expanding. 

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For decades,
astronomers assumed gravity

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would gradually slow that expansion. 

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Then, in 1998, observations of distant

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exploding stars revealed
something unexpected:  

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The expansion of
the universe is speeding up.

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Something appears to be
pushing the cosmos apart. 

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Scientists call that unknown 
influence dark energy. 

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Today, dark energy is thought to account for roughly

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68 percent of the universe,  

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yet its true nature remains one of 
the greatest mysteries in physics. 

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Roman will approach
this problem using

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multiple independent techniques.

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It will map the positions of millions of galaxies in three dimensions,

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study distant supernova explosions,  

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and measure how light bends through a phenomenon

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known as gravitational lensing. 

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Together, these observations
will allow scientists

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to trace how the universe
has changed over  

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billions of years and
test whether dark energy

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has remained constant
or evolved over time.

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Roman will also help illuminate 
another cosmic mystery: dark matter. 

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Although invisible,
dark matter exerts a

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gravitational pull and
appears to make up most  

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of the matter the universe is made of.

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Astronomers can infer its presence

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because galaxies and 
galaxy clusters behave as though

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they contain far more
mass than we can see.

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Something is there. 

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Roman will map both
visible matter and dark matter

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across enormous stretches of space  

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by measuring small changes in the shapes of distant galaxies.

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These measurements
will provide one of

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the most detailed views 
ever created

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of how matter is distributed  

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throughout the cosmos
and how large objects

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like galaxies evolved
over cosmic history.

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Closer to home,
Roman will also conduct

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one of the most
ambitious searches for  

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planets beyond our solar system.

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Most exoplanets discovered so far  

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have been found
using the transit method,

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which detects tiny dips
in starlight when a  

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planet crosses in front of its host star.

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Roman will complement
those discoveries  

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by primarily using a technique 
called gravitational microlensing. 

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When a star passes in front of a 
more distant star, gravity bends  

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and magnifies the
background starlight.

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If a planet is orbiting
the foreground star, it  

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leaves a distinctive
fingerprint in that signal.

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By continuously
monitoring millions of stars in  

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the crowded center of the Milky Way,

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Roman is expected to discover thousands of new worlds,  

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including planets smaller than Mars,

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planets orbiting far from their stars,

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and even rogue planets
drifting freely through space.

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These discoveries will help astronomers  

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build the most
complete census yet of

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planetary systems
throughout our galaxy.

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Roman will also carry
a Coronagraph Instrument,

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a technology demonstration
designed to block  

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the overwhelming
glare of nearby stars.

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This will allow astronomers
to directly image giant  

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exoplanets and dusty disks
around neighboring stars,

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helping pave the way
toward future missions  

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capable of finding Earth-like worlds.

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Beyond its primary investigations,  

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Roman's vast surveys will become 
a treasure trove for astronomy.

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The mission is expected to discover

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some of the earliest
galaxies in the universe,  

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uncover distant quasars powered
by supermassive black holes, 

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reveal streams of stars
swirling into nearby galaxies,

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and provide an unprecedented
map of the cosmos

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stretching back to when the universe was only a fraction of its current age.

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Many of the most important discoveries may be  

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things astronomers aren't
even expecting to find.

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That's because Roman
is designed not just to  

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study individual objects, but 
to reveal the bigger picture. 

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The phenomena Roman will detect
in its wide field images

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will be followed up with detailed,  

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higher resolution studies
by Hubble and Webb,

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which together cover wavelengths of  

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light ranging from ultraviolet to mid-infrared.

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Along with observatories like Hubble, Webb,

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ESA’s Euclid mission, and
the Vera C. Rubin Observatory,

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Roman will usher in
a new era of discovery,  

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giving scientists an unprecedented
view of the universe

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and bringing us closer
to answering some  

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of humanity's oldest questions...

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What is the universe made of? 

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How did it become
what we see today?

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And what will its ultimate fate be? 

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The Nancy Grace
Roman Space Telescope

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was built to help us find out.

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[ NASA MEATBALL!!!!! ]