Nancy Grace Roman Telescope

fredymac said:
The Wikipedia link says using a spare NRO telescope mirror

“.... provided important political momentum to the project, even though the telescope represents only a modest fraction of the cost of the mission and the boundary conditions from the NRO design may push the total cost over that of a fresh design.”

which was my point. I don’t think (or at least hope) nobody would propose a follow on Hubble just because a spare primary exists. WFIRST proposals may have sidetracked themselves using the spare mirror argument rather than sticking with a telescope design optimized for the requirements. If mapping dark energy effects is important, it can compete directly on that basis.
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The original WFIRST mission proposal was for a much smaller mirror, the whole thing built from scratch. This would have been cheaper, according to just about everybody.

Former NASA Associate Administrator for the Science Mission Directorate John Grunsfeld (essentially the guy at NASA who was then in charge of all the science stuff) said a number of times in public that he could not find political support to fund that proposal. It was not until after the NRO mirror became available that the political leadership (White House, Congress) became interested in WFIRST. So, according to Grunsfeld, it was the case of do you want the original proposal, which nobody is going to fund, or do you want this new one, which is different, and will cost more, but which people will fund?

Now there are people who disagreed with Grunsfeld and argued that NASA should have stuck to the original specifications, but they were not in the position that he was. He saw the funding situation differently.

The new much larger WFIRST mirror does some different science than the original proposal. Essentially, it trades off looking farther into the infrared (because the mirror cannot get colder) in return for much larger collection area. So some scientists are unhappy with the loss of the farther IR, and some scientists are happy with the greater collecting power.

It's common to simply heap scorn on NASA and say that they cannot manage anything and keep it on cost. But who else does this stuff? Who is better at doing these things than NASA? These things are not easy to do. And this is a case where, at least according to a senior NASA official, the cheaper WFIRST option simply was not exciting enough to get funded. So do you want 100% of nothing or 80% of something? That was apparently the choice in this case.

(Oh, there are a lot more complicated aspects to this as well, like the number of instruments and how the astrophysics community uses these big telescopes. These are just the basic ones.)
 
blackstar said:
The original WFIRST mission proposal was for a much smaller mirror, the whole thing built from scratch. This would have been cheaper, according to just about everybody.

Former NASA Associate Administrator for the Science Mission Directorate John Grunsfeld (essentially the guy at NASA who was then in charge of all the science stuff) said a number of times in public that he could not find political support to fund that proposal. It was not until after the NRO mirror became available that the political leadership (White House, Congress) became interested in WFIRST. So, according to Grunsfeld, it was the case of do you want the original proposal, which nobody is going to fund, or do you want this new one, which is different, and will cost more, but which people will fund?

Now there are people who disagreed with Grunsfeld and argued that NASA should have stuck to the original specifications, but they were not in the position that he was. He saw the funding situation differently.

The new much larger WFIRST mirror does some different science than the original proposal. Essentially, it trades off looking farther into the infrared (because the mirror cannot get colder) in return for much larger collection area. So some scientists are unhappy with the loss of the farther IR, and some scientists are happy with the greater collecting power.

It's common to simply heap scorn on NASA and say that they cannot manage anything and keep it on cost. But who else does this stuff? Who is better at doing these things than NASA? These things are not easy to do. And this is a case where, at least according to a senior NASA official, the cheaper WFIRST option simply was not exciting enough to get funded. So do you want 100% of nothing or 80% of something? That was apparently the choice in this case.

(Oh, there are a lot more complicated aspects to this as well, like the number of instruments and how the astrophysics community uses these big telescopes. These are just the basic ones.)
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Who is better at doing these things? Let's find out and set up alternative approaches.

Science proposals compete to win approval based on the overall level of interest and available budget. WFIRST winning necessarily means other projects wait. WFIRST is not the only project examining dark energy/dark matter. The Large Synoptic Survey Telescope (now called Rubin Telescope) is also addressing this subject and is already well into hardware integration. The ESA Gaia space telescope also collects data pertinent to analyzing dark matter. WFIRST was competing as an additional experiment rather than a unique asset. Waiting to see the results of these other efforts could have revealed a genuine area of importance that could use a dedicated mission.
 
fredymac said:
Who is better at doing these things? Let's find out and set up alternative approaches.

Science proposals compete to win approval based on the overall level of interest and available budget. WFIRST winning necessarily means other projects wait. WFIRST is not the only project examining dark energy/dark matter. The Large Synoptic Survey Telescope (now called Rubin Telescope) is also addressing this subject and is already well into hardware integration. The ESA Gaia space telescope also collects data pertinent to analyzing dark matter. WFIRST was competing as an additional experiment rather than a unique asset. Waiting to see the results of these other efforts could have revealed a genuine area of importance that could use a dedicated mission.
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I suspect you don't understand how the prioritization is done and the money is then appropriated to different programs.

Also, WFIRST is more than dark energy/dark matter.
 
blackstar said:
I suspect you don't understand how the prioritization is done and the money is then appropriated to different programs.

Also, WFIRST is more than dark energy/dark matter.
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I'm not sure why you think selection of programs is so complex and nuanced that you couldn't just sum it up in a sentence or two. The politics of using the "spare telescope" however reveals it isn't any different than other government program awards.

As for the mission of WFIRST from their own website:
The Roman Space Telescope is a NASA observatory designed to unravel the secrets of dark energy and dark matter, search for and image exoplanets, and explore many topics in infrared astrophysics.

Dark Energy and Dark Matter are the hot topics that are drawing public interest and funding. Basically, any wide field telescope can engage in this activity and any telescope can be be applied to multiple purposes. I expect LSST will actually achieve more science in this regards.
 
fredymac said:
Who is better at doing these things? Let's find out and set up alternative approaches.

I'm not sure why you think selection of programs is so complex and nuanced that you couldn't just sum it up in a sentence or two.
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Because you don't even understand the context.
a. He means better at managing spacecraft development.
b. LSST doesn't enter the discussion because it is not space based.
c. Program selection meaning NASA spacecraft programs.
 
Byeman said:
Because you don't even understand the context.
a. He means better at managing spacecraft development.
b. LSST doesn't enter the discussion because it is not space based.
c. Program selection meaning NASA spacecraft programs.
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a. Like JWST
b. Same primary mission regardless
c. Of course. So what.

Try responding with something other than an ad hominem and which has some rational basis.
 
This project has been particularly badly hit by the pandemic in terms of time and cost.

spacenews.com

Pandemic to cost NASA up to $3 billion

A NASA audit concluded that costs imposed by the COVID-19 pandemic on the agency could reach $3 billion, with several major science and exploration programs accounting for much of that cost.
spacenews.com spacenews.com
 
As that article notes, a key issue was that the telescope was at its peak funding point when the pandemic hit. It's easy to not spend a lot of money when you're not spending a lot of money.
I know some NASA people who have been locked out of their labs for a year. They were planning on building instruments to go on spacecraft, and they just have not been able to do that. It's going to have a sliding effect on a lot of schedules. Until they can get back into their facilities and start building again, they won't know their schedules. And they won't know the budget impacts.
 
NASA’s Roman Mission Predicted to Find 100,000 Transiting Planets

NASA’s Nancy Grace Roman Space Telescope will create enormous cosmic panoramas, helping us answer questions about the evolution of our universe. Astronomers also expect the mission to find thousands of planets using two different techniques as it surveys a wide range of stars in the Milky Way.

Roman will locate these potential new worlds, or exoplanets, by tracking the amount of light coming from distant stars over time. In a technique called gravitational microlensing, a spike in light signals that a planet may be present. On the other hand, if the light from a star dims periodically, it could be because there is a planet crossing the face of a star as it completes an orbit. This technique is called the transit method. By employing these two methods to find new worlds, astronomers will capture an unprecedented view of the composition and arrangement of planetary systems across our galaxy.
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www.nasa.gov

NASA’s Roman Mission Predicted to Find 100,000 Transiting Planets - NASA

NASA’s Nancy Grace Roman Space Telescope will create enormous cosmic panoramas, helping us answer questions about the evolution of our universe. Astronomers
www.nasa.gov www.nasa.gov
 
NASA’s Nancy Grace Roman Space Telescope has successfully passed its critical design review, signaling that all design and developmental engineering work is now complete.

“After seeing our extensive hardware testing and sophisticated modeling, an independent review panel has confirmed that the observatory we have designed will work,” said Julie McEnery, the Roman Space Telescope senior project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “We know what it will look like and what it will be capable of. Now that the groundwork is laid, the team is thrilled to continue building and testing the observatory they’ve envisaged.”
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www.nasa.gov

NASA Confirms Roman Mission's Flight Design in Milestone Review - NASA

Editor’s Note, 14 Oct. 2021: NASA has completed an independently verified replan for the Nancy Grace Roman Space Telescope due to significant
www.nasa.gov www.nasa.gov
 
https://twitter.com/x/status/1448769955533672454
View: https://twitter.com/SpcPlcyOnline/status/1448769955533672454

Further to my earlier tweets about the cost increase for the Roman space telescope due to COVID, it is $382 million over the lifetime of the project, lifting it to $4.3 B. Here is the formal statement I just got from NASA.
h/t to Roman project scientist @DominicBenford
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https://twitter.com/x/status/1448808822441717762
View: https://twitter.com/jeff_foust/status/1448808822441717762

This is consistent with NASA OIG’s projection of a $400M increase back in March. (I asked NASA about this a couple weeks ago but never got an answer.) https://spacenews.com/pandemic-causes-delay-and-cost-increase-for-nasas-roman-space-telescope/
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Tangential, beyond logging umpteen more 'transits', big result would be proving the bold sun-shade and modular mirror tech. Seems scalable as follow-up to big Euro-scope planned to multi-pixel image some of the exo-planets which continue to surface in our 'neighbourhood'. My quotes, as even a few light-years are still a really, really long way...

The problem with the prolific Doppler detection technique is figuring the orbital inclination. I'd like that for tau Ceti. Non-transiting family of planets, 'f' at chill end of hab-zone but mass is 'Sin(i)', could be any-where from 3~~5+ Earths. There's an outer asteroid belt / debris field at ~35º, but the inner system, including 'f' seems tilted otherwise...
 
Launch has been awarded to Space X using a Falcon Heavy, with a launch date of October 2026.

https://twitter.com/x/status/1549492284932050944
View: https://twitter.com/spacex/status/1549492284932050944


NASA has selected Falcon Heavy to launch the Roman Space Telescope, which is designed to study dark energy and dark matter, search for and image exoplanets, and more. Liftoff is targeted for no earlier than October 2026 from Launch Complex 39A in Florida
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www.nasa.gov

NASA Awards Launch Services Contract for Roman Space Telescope

NASA has selected Space Exploration Technologies Corporation (SpaceX) in Hawthorne, California, to provide launch service for the Nancy Grace Roman Space Telescope mission.
www.nasa.gov www.nasa.gov

Jul 19, 2022
CONTRACT RELEASE C22-015

NASA Awards Launch Services Contract for Roman Space Telescope

NASA has awarded a NASA Launch Services (NLS) II contract to Space Exploration Technologies Corporation (SpaceX) in Hawthorne, California, to provide launch service for the Nancy Grace Roman Space Telescope mission. The Roman Space Telescope is the top-priority large space mission recommended by the 2010 Astronomy and Astrophysics Decadal Survey.

NLS II is an indefinite-delivery/indefinite-quantity contract. The total cost for NASA to launch the Roman telescope is approximately $255 million, which includes the launch service and other mission related costs. The telescope’s mission currently is targeted to launch in October 2026, as specified in the contract, on a Falcon Heavy rocket from Launch Complex 39A at NASA’s Kennedy Space Center in Florida.

The telescope’s science program will include dedicated investigations to tackle outstanding questions in cosmology, including the effects of dark energy and dark matter, and exoplanet exploration. Roman also includes a substantial general investigator program to enable further studies of astrophysical phenomena to advance other science goals.

The telescope was previously known as the Wide Field InfraRed Survey Telescope (WFIRST), but it was later renamed in honor of Dr. Nancy Grace Roman for her extraordinary work at NASA, which paved the way for large space telescopes.

NASA’s Launch Services Program at Kennedy is responsible for launch vehicle program management of the SpaceX launch service. The Roman Space Telescope project is managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

For more information about NASA programs and missions, visit:

www.nasa.gov

NASA

NASA.gov brings you the latest news, images and videos from America's space agency, pioneering the future in space exploration, scientific discovery and aeronautics research.
www.nasa.gov www.nasa.gov

-end-
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Flyaway said:
https://twitter.com/x/status/1549493958086213633
View: https://twitter.com/jeff_foust/status/1549493958086213633


May 2027 is the formal launch commitment date (no later than) for Roman, but the target is still October 2026.
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May 2027 for the launch commitment date for Roman Space Telescope Flyaway? I would have thought that it would have been better to go for the October 2026 date. Plus it is good to see NASA select the SpaceX Falcon Heavy rocket as the launch vehicle.
 
I would like to see a Centaur as an upper stage. Congrats to SpaceX.
 
NASA’s Roman Mission Completes Key Optical Components

Engineers at Ball Aerospace, one of the industrial partners for NASA’s Nancy Grace Roman Space Telescope, have installed and aligned the element wheel assembly (pictured above) into the telescope’s Wide Field Instrument. The assembly contains eight science filters, two dispersive elements (a grism and prism) and a “blank” element (used for internal calibration) that will help scientists solve some of the most profound mysteries in astrophysics when Roman launches by May 2027.

After light is reflected and focused by Roman’s primary and secondary mirrors, it will pass through the element wheel. The focused and filtered light will then reach a large detector array, where an image is created. Depending on what the researchers are looking for, the science filters will allow astronomers to select specific wavelengths of light for their observations. The grism and prism are tools for spectroscopy, designed to spread out the light from cosmic objects into different colors. These rainbow-like measurements, called spectra, contain unique signatures about the sources that offer clues about their nature. For example, astronomers will be able to measure how thousands of entire galaxies are moving through space, which will help them see how fast the universe has expanded at different points in time. Doing so can help pin down the nature of dark energy – the mysterious cosmic pressure that’s speeding up the universe’s expansion.

The grism and prism were fabricated and tested by Optimax, Jenoptik, and NASA’s Goddard Space Flight Center to ensure they meet Roman’s stringent requirements. The team simulated space-like conditions in a cryo-vacuum vessel, which lowered the temperature to about minus 190 degrees Fahrenheit (minus 123 degrees Celsius). Since most materials expand when heated and compress when cooled, engineers had to confirm that the optics will work as planned at Roman’s super-cold operating temperature. Both the grism and prism passed, with test images showing minimal distortion. Astronomers will use these components to explore some of the biggest mysteries in the universe.
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Flyaway said:
NASA’s Roman Mission Completes Key Optical Components

Engineers at Ball Aerospace, one of the industrial partners for NASA’s Nancy Grace Roman Space Telescope, have installed and aligned the element wheel assembly (pictured above) into the telescope’s Wide Field Instrument. The assembly contains eight science filters, two dispersive elements (a grism and prism) and a “blank” element (used for internal calibration) that will help scientists solve some of the most profound mysteries in astrophysics when Roman launches by May 2027.

After light is reflected and focused by Roman’s primary and secondary mirrors, it will pass through the element wheel. The focused and filtered light will then reach a large detector array, where an image is created. Depending on what the researchers are looking for, the science filters will allow astronomers to select specific wavelengths of light for their observations. The grism and prism are tools for spectroscopy, designed to spread out the light from cosmic objects into different colors. These rainbow-like measurements, called spectra, contain unique signatures about the sources that offer clues about their nature. For example, astronomers will be able to measure how thousands of entire galaxies are moving through space, which will help them see how fast the universe has expanded at different points in time. Doing so can help pin down the nature of dark energy – the mysterious cosmic pressure that’s speeding up the universe’s expansion.

The grism and prism were fabricated and tested by Optimax, Jenoptik, and NASA’s Goddard Space Flight Center to ensure they meet Roman’s stringent requirements. The team simulated space-like conditions in a cryo-vacuum vessel, which lowered the temperature to about minus 190 degrees Fahrenheit (minus 123 degrees Celsius). Since most materials expand when heated and compress when cooled, engineers had to confirm that the optics will work as planned at Roman’s super-cold operating temperature. Both the grism and prism passed, with test images showing minimal distortion. Astronomers will use these components to explore some of the biggest mysteries in the universe.
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Things are certainly coming along with the RST.
 
Assembly Begins On Roman Space Telescope Coronagraph Instrument Color Filter Assembly To Study Exoplanets
By Keith Cowing
Press Release
NASA
December 25, 2022

The filters on NASA’s Roman Space Telescope Coronagraph Instrument’s Color Filter Assembly each block all but a specific color, or wavelength, of light. Many of the filters appear dark in this photo because they are transparent only to infrared light, which is invisible to the human eye. Credit: NASA/JPL-Caltech
NASA

The Coronagraph Instrument on NASA’s Nancy Grace Roman Space Telescope will study planets around other stars. Putting it together will require a highly choreographed dance.

Scientists have discovered more than 5,000 exoplanets, or planets outside our solar system. As technologies for studying these worlds continue to advance, researchers may someday be able to search for signs of life on exoplanets that are similar in size, composition, and temperature to Earth. But to do that they’ll need new tools, like those being tested on the Coronagraph Instrument on NASA’s Nancy Grace Roman Space Telescope. The science instrument will block the light from each distant star it observes so that scientists can better see the planets around the star, and it will demonstrate technologies needed to eventually study potentially habitable planets with future missions.

The Coronagraph Instrument team has already designed the cutting-edge instrument and built the components. Now they have to put the pieces together and run tests to make sure they operate as intended. “It’s like all the separate tributaries are finally coming together to form the river,” said Jeff Oseas, product delivery manager for the Coronagraph Instrument’s optical subsystem at NASA’s Jet Propulsion Laboratory in Southern California.

The process kicked off recently at JPL and will take more than a year. Once complete, the Coronagraph Instrument will be shipped to the agency’s Goddard Space Flight Center in Greenbelt, Maryland, and incorporated into the Roman observatory.

JPL engineer Gasia Bedrosian leads the assembly and testing process as the instrument’s integration and test product delivery manager. She likes to say that while integration and testing are technically the last steps in building an instrument, they’re actually part of the process from the beginning.

In 2018, Bedrosian started working on a set of assembly plans for something that’s never been built before. She and her team then spent another two years collaborating with various subject matter experts and project members to review and adjust the plan, ensuring all the pieces would come together on time and in the right order. The process will resemble a well-choreographed ballet that involves heavy duty cranes, lasers, and vacuum chambers the size of buses.

Roughly the size and shape of a baby grand piano, the Coronagraph Instrument is composed of two main sections that will stack on top of each another: the optical bench and the instrument electronics pallet.
The more delicate of the two is the optical bench, which contains 64 elements, such as mirrors and filters, designed to remove as much starlight as possible without suppressing the light from planets. This approach to finding and studying exoplanets is called direct imaging, and it is expected to be the best way to study the atmospheres and surface features of rocky worlds similar to Earth. Some of the optical components on the Coronagraph Instrument are so small they’re barely visible to the naked eye.

The pallet, or bottom layer, houses the electronics that receive instructions from the Roman spacecraft and return the Coronagraph Instrument’s scientific data. The electronics also control the mechanical components on the optical bench as well as the instrument heaters. The optical bench will be stacked by crane atop the electronics pallet. Because the two layers have to be aligned with each other to within a fraction of a millimeter, the team will use lasers to get them positioned just right over the course of four days.

Eye for Detail

Integration and testing teams will often use digital 3D models of the instrument to help make their plans, but nothing can compare to seeing the object in a real space. That’s why the coronagraph team made use of an augmented reality headset that lets users see a virtual projection of a 3D object and the world around them. The headset is also used by the Mars Curiosity rover team to see in 3D the Martian terrain that the rover drives over.

“We learned a lot from that exercise,” said Bedrosian. “We could get a sense of how tight the access would be at certain points of integration by literally laying on the floor and getting visuals of under the instrument. It showed us when it would be beneficial to lift the entire instrument with a crane, or if we were going to need a specialized tool to do our work at that angle. It helped make a lot of our plans safer and simpler.”

Once assembled, the Coronagraph Instrument will undergo a series of tests, including almost a month of dynamical testing to simulate the rocket ride into space. It will then be put in a vacuum chamber that replicates the space environment to check that the hardware remains aligned and operating correctly.
“It’s exciting to finally start putting all the pieces together,” said Bedrosian. “It’s definitely a delayed gratification, because we’ve spent so long preparing. But now that we’re here and my team members are talking about the hardware arriving, I can hear the excitement in their voices.”

More About the Mission

The Nancy Grace Roman Space Telescope is managed at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, with participation by JPL and Caltech/IPAC in Southern California, the Space Telescope Science Institute in Baltimore, and a science team comprising scientists from various research institutions. The primary industrial partners are Ball Aerospace & Technologies Corp. in Boulder, Colorado; L3Harris Technologies in Melbourne, Florida; and Teledyne Scientific & Imaging in Thousand Oaks, California.

The Roman Coronagraph Instrument was designed and is being built at JPL, which manages the instrument for NASA. Contributions were made by ESA (the European Space Agency), the Japanese Aerospace Exploration Agency (JAXA), the French space agency Centre National d’Études Spatiales (CNES), and the Max Planck Institute for Astronomy (MPIA) in Germany. Caltech, in Pasadena, California, manages JPL for NASA.

For more information about the Roman telescope, visit: https://roman.gsfc.nasa.gov/

www.nasa.gov

Assembly Begins on NASA’s Next Tool to Study Exoplanets

The Coronagraph Instrument on NASA’s Nancy Grace Roman Space Telescope will study planets around other stars. Putting it together will require a highly choreographed dance.
www.nasa.gov www.nasa.gov
 
With a dish this big, we can stay connected even a million miles away in space! The Nancy Grace Roman Space Telescope’s high-gain antenna has passed a series of tests at the NASA Goddard Space Flight Center!
1f4e1.svg
Learn more: https://go.nasa.gov/3HvoD2c
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https://twitter.com/x/status/1622619546447216640
View: https://twitter.com/nasaroman/status/1622619546447216640?s=46&t=_MPicFVPhdMbECW9wkdu5Q
 
www.nasa.gov

Goddard Team Builds, Tests Calibrator for NASA’s Roman in Record Time

A vital subsystem for NASA’s Nancy Grace Roman Space Telescope was recently installed in the spacecraft’s Wide Field Instrument. Called the Simplified Relative Calibration System (sRCS), this component will allow astronomers to measure the total light output of cosmic objects like galaxies and...
www.nasa.gov www.nasa.gov
 

Framework for NASA’s Roman Spacecraft Moves to Goddard Clean Room​

www.nasa.gov

Framework for NASA’s Roman Spacecraft Moves to Goddard Clean Room

The primary structure that serves as the “bones” of NASA’s Nancy Grace Roman Space Telescope just moved into the clean room at the Goddard Space Flight Center. The rest of the spacecraft will be built up on this skeletal structure.
www.nasa.gov www.nasa.gov
 
https://twitter.com/x/status/1658476040921174023
View: https://twitter.com/NASARoman/status/1658476040921174023

Roman's heart will go on... to @BallAerospace!! Roman's focal plane assembly, the 'heart' of Roman's Wide Field Instrument, had its final looks and inspections at @NASAGoddard and is now at Ball Aerospace, where it will now be integrated into the instrument. Learn more: https://go.nasa.gov/3W8anU2
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www.nasa.gov

NASA Completes Heart of Roman Space Telescope’s Primary Instrument

The heart of NASA’s Nancy Grace Roman Space Telescope was recently delivered to Ball Aerospace for integration into the WFI (Wide Field Instrument). Called the FPS (Focal Plane System), it serves as the core of Roman’s camera.
www.nasa.gov www.nasa.gov
 
https://twitter.com/x/status/1795515462861644040
View: https://twitter.com/nasaroman/status/1795515462861644040


OMG @NASAJPL!! You shouldn't have!! Let's unbox the Roman Coronagraph!

This instrument is one of two to be installed into the spacecraft's instrument carrier.
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www.jpl.nasa.gov

NASA Tool Gets Ready to Image Faraway Planets

A technology demo on the Nancy Grace Roman Space Telescope will help increase the variety of distant planets scientists can directly image.
www.jpl.nasa.gov www.jpl.nasa.gov

View: https://youtu.be/_1zfz-OEKH8
 
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NASA Tests Deployment of Roman Space Telescope’s ‘Visor’ [Aug 9]

The “visor” for NASA’s Nancy Grace Roman Space Telescope recently completed several environmental tests simulating the conditions it will experience during launch and in space. Called the Deployable Aperture Cover, this large sunshade is designed to keep unwanted light out of the telescope. This milestone marks the halfway point for the cover’s final sprint of testing, bringing it one step closer to integration with Roman’s other subsystems this fall.

Designed and built at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, the Deployable Aperture Cover consists of two layers of reinforced thermal blankets, distinguishing it from previous hard aperture covers, like those on NASA’s Hubble. The sunshade will remain folded during launch and deploy after Roman is in space via three booms that spring upward when triggered electronically.

“With a soft deployable like the Deployable Aperture Cover, it’s very difficult to model and precisely predict what it’s going to do — you just have to test it,” said Matthew Neuman, a Deployable Aperture Cover mechanical engineer at Goddard. “Passing this testing now really proves that this system works.”

During its first major environmental test, the sunshade endured conditions simulating what it will experience in space. It was sealed inside NASA Goddard’s Space Environment Simulator — a massive chamber that can achieve extremely low pressure and a wide range of temperatures. Technicians placed the DAC near six heaters — a Sun simulator — and thermal simulators representing Roman’s Outer Barrel Assembly and Solar Array Sun Shield. Since these two components will eventually form a subsystem with the Deployable Aperture Cover, replicating their temperatures allows engineers to understand how heat will actually flow when Roman is in space.

When in space, the sunshade is expected to operate at minus 67 degrees Fahrenheit, or minus 55 degrees Celsius. However, recent testing cooled the cover to minus 94 degrees Fahrenheit, or minus 70 degrees Celsius — ensuring that it will work even in unexpectedly cold conditions. Once chilled, technicians triggered its deployment, carefully monitoring through cameras and sensors onboard. Over the span of about a minute, the sunshade successfully deployed, proving its resilience in extreme space conditions.

“This was probably the environmental test we were most nervous about,” said Brian Simpson, project design lead for the Deployable Aperture Cover at NASA Goddard. “If there’s any reason that the Deployable Aperture Cover would stall or not completely deploy, it would be because the material became frozen stiff or stuck to itself.”

If the sunshade were to stall or partially deploy, it would obscure Roman’s view, severely limiting the mission’s science capabilities.

After passing thermal vacuum testing, the sunshade underwent acoustic testing to simulate the launch’s intense noises, which can cause vibrations at higher frequencies than the shaking of the launch itself. During this test, the sunshade remained stowed, hanging inside one of Goddard’s acoustic chambers — a large room outfitted with two gigantic horns and hanging microphones to monitor sound levels.

With the sunshade plastered in sensors, the acoustic test ramped up in noise level, eventually subjecting the cover to one full minute at 138 decibels — louder than a jet plane’s takeoff at close range! Technicians attentively monitored the sunshade’s response to the powerful acoustics and gathered valuable data, concluding that the test succeeded.

“For the better part of a year, we’ve been building the flight assembly,” Simpson said. “We’re finally getting to the exciting part where we get to test it. We’re confident that we’ll get through with no problem, but after each test we can’t help but breathe a collective sigh of relief!”

Next, the Deployable Aperture Cover will undergo its two final phases of testing. These assessments will measure the sunshade’s natural frequency and response to the launch’s vibrations. Then, the Deployable Aperture Cover will integrate with the Outer Barrel Assembly and Solar Array Sun Shield this fall.
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View: https://www.youtube.com/watch?v=RqJvDpDoevE
 

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