NASA’s Nancy Grace Roman Space Telescope team has successfully activated the Wide Field Instrument, a 300-megapixel infrared camera that will allow scientists to explore wide swaths of the cosmos very quickly without sacrificing exquisite detail.
Roman’s planet imager — the Coronagraph Instrument — also stretched its
digital, electronic, and mechanical “limbs” as part of an initial test after waking up earlier this month.
These steps are part of a monthslong series of calibrations and tests, as
Roman continues its million-mile journey to its destination at the second
Lagrange point, L2.
Sky-scanner comes online
Each image taken by the Wide Field Instrument, or WFI, will capture a patch
of the sky bigger than the apparent size of a full moon with all the sharpness
of space telescopes like NASA’s Hubble. Its sweeping cosmic surveys will help
scientists discover new information about planets beyond our solar system, untangle mysteries like dark energy, and map how matter is structured and distributed
throughout the cosmos. The mission’s broad, crisp view will also produce an
exciting new resource for a wide range of additional scientific studies.
Watch this video to learn more about the Roman Space Telescope’s Wide
Field Instrument.
NASA’s Goddard Space Flight Center, Music credit:
“Horizon Ahead” from Universal Production Music
“After
years of effort to build and test the instrument on the ground, we now have
confirmation that it is operational in space. This is a huge milestone for the
team at Goddard, our industry teams at BAE Systems, Inc. and Teledyne, and our
science centers,” said Josh Schlieder, the Wide Field Instrument scientist at
NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “There is much to
do, but we are on our way to groundbreaking science.”
Before the team could activate the WFI, they had to
let it rest for 10 days to dry out and decontaminate with the detectors at a
relatively warm (compared to their final operating temperature) minus 85
degrees Fahrenheit, or minus 65 Celsius. On the morning of Sep. 11, they turned
off the instrument heater and let the WFI cool down to minus 225 Fahrenheit
(minus 143 Celsius), at which point they could activate Roman’s 18 infrared
detectors, which combined have a sensing area about the size of a laptop screen.
Scientists and engineers in the launch support room at
NASA’s Goddard Space Flight Center in Greenbelt, Md., celebrate the activation
of Roman’s Wide Field Instrument.
NASA/Sophia Roberts
Later
that night, the team activated the calibration system, which they used the next
morning to start sending test data through the instrument and down to engineers
on the ground. On Saturday evening, the focus shifted to the element wheel
— a system of filters, prisms, and other optics used to tune the
wavelengths of light that reach the detectors and spread light from cosmic
objects into individual colors — as engineers tested it in the absence of
gravity for the very first time.
Finally, on Sunday morning, the team made sure the
WFI’s focus mechanism functions properly — an important step since it will be
used to focus the hundreds of thousands of images the instrument will take.
While these activities were happening, the detectors continued to cool to their
final temperature of about minus 300 Fahrenheit (minus 183 Celsius).
This test image captures the very first photons of
starlight to reach the Wide Field Instrument on NASA’s Nancy Grace Roman Space
Telescope. It was taken as an initial performance assessment with the detector
array still stowed as it was for launch, far from best focus. Roman’s primary
science instrument has opened its eyes to the universe for the first time,
revealing a sea of out-of-focus stars, each spread out over many thousands of
pixels. The image, which zooms into one detector and zooms again to a single
star in the insets, offers a baseline the Roman team will work from to align
the telescope’s optics and tune the focus. The team will soon activate the
instrument’s fine-guidance system, which will mean Roman can lock onto targets.
They’ll also focus the observatory, which will shrink each star’s light to
appear as a crisp point, rather than the broad, donut-like features seen here
(which appear as expected given the instrument’s present configuration).
Roman’s science images, which NASA expects to release by early 2027, will be
much sharper and reveal the cosmos in exquisite detail.
NASA’s Goddard Space Flight Center, Tyler Desjardins
(STScI)
All of these assessments confirmed the instrument is working as expected.
The mission remains on track to release Roman’s first science images by early
2027.
Coronagraph in tip-top shape
The Roman Coronagraph is a system of optics, masks, self-flexing mirrors,
and sensors designed to demonstrate the most advanced technologies ever flown
in space for directly imaging planets around other stars. It will block the glare
from stars and make it possible for scientists to see the faint reflected light
from planets in orbit around them.
Scientists and engineers at the Coronagraph Commanding Center at
Caltech/IPAC in Pasadena, California, confirmed they can communicate with all
of the instrument’s components: software, thermal control, mechanisms, cameras,
and the avionics which drive all of these. Essentially, operators on the ground
ensured they could remotely flip all the switches that allow them to control
the instrument, like the movable mechanisms that hold all of its masks, color
filters, lenses, and prisms.
This image displays the “shaped pupil” masks, each
about the size of a U.S. quarter, used in the Nancy Grace Roman Space
Telescope’s Coronagraph Instrument. These precisely engineered components
modify the diffraction pattern of starlight to block glare and reveal faint
regions surrounding stars.
NASA/Chris Gunn
The
test also involved confirming that the thermal control is performing as
expected, warming the hardware to operating temperatures — a balmy 72 degrees
Fahrenheit (22 Celsius). Aside from the detectors, the coronagraph is designed
to work at near-room temperature to make it easier to test and to match the
material properties of the deformable mirrors.
“Now that this test is complete, we’ve been
decontaminating: sitting idle with our detectors warm so anything that’s stuck
to the surface, such as water or trace chemicals, will tend to leave it,” said
Eric Cady, an optical engineer leading commissioning efforts for the Roman
Coronagraph at NASA’s Jet Propulsion Laboratory in Southern California. “This
will continue for 30 days, with occasional stops to do other early calibration
activities.”
To learn more about Roman’s commissioning process, visit: Roman Commissioning - NASA Science
Source: NASA Activates Roman’s Primary Instrument, Checks Out Coronagraph - NASA Science
