Nancy Grace Telescope Part 3
2017:
The plan was going well, and we were working toward our goal. It was going perfectly with the new coronagraph installed, making it easier for astronomers to directly image planets by blocking out the star's light with a “sunshade”, and the astronomy team was happy with how the building of the telescope was going.
But then NASA limited the growth of the Nancy Grace Telescope by setting a strict 3.2 billion budget.
Now you might be saying that 3.2 billion dollars is a lot, right? But for a big project like the Nancy Grace Space Telescope, it is very little.
Let's take an example. Hubble cost 1 billion dollars to launch and 10 billion dollars to maintain.
Since the Nancy Grace Space Telescope is a telescope made to image the Earth and not space, there had to be a lot of changes made, which would usually cause panic through the astronomy society about how we should finish the telescope with such a low budget.
To add to the problems was a huge debate between astronomers and engineers about how they should continue the project with that huge budget cut.
So the engineers considered cutting the mirror
But cutting the mirror could hinder the search for more galaxies and dark energy in the universe. So the scientific debate started.
Somewhere in another part of the industry, there was a heat crisis that couldn't be ignored. The mirror is made to be able to withstand the heat of 33°F; it might seem like a small amount, but it is actually average. But the cold of deep space is too much to ignore: -300°F.
2018:
After years of brutal initial design challenges, solutions to the telescope’s compounding structural crises began to come in during the opening months of 2018, albeit with some of the most painful compromises in recent memory.
In order to prevent outright cancellation of the telescope’s discovery mission under the new 3.2 billion dollar NASA budget cap, NASA Headquarters took the painful action of downgrading the cutting-edge Coronagraph Instrument to a scaled-back technology demonstration in January, in order to free up funds.
This allowed them to keep the baseline discovery mission within the budget while crippling its planetary-finding potential.
Meanwhile, engineers puzzled out an innovative active hardware solution to the telescope’s deep space temperature problem.
By wrapping the mirror in an Integrated Thermal Control System containing 192 independently controlled heaters, they were able to keep the surface of the mirror at a stable 265 Kelvin (about 17degrees Fahrenheit).
This prevented the support structure from constricting and deforming the mirror due to the cold, while keeping the sensitive infrared camera optics at a frigid but survivable temperature.
In November, NASA formally awarded the contract to Harris Corporation to begin construction of the flight optics.
However, just as things seemed to be settling down, a larger political issue arose when the White House announced its FY 2019 federal budget request and promptly zeroed out the telescope’s funding.
The President argued that NASA’s resources would be better spent focusing on his agency’s own massively delayed James Webb Space Telescope, rather than starting up a new megaproject.
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For the duration of the year, engineers scrambled to modify and test components while working on a phantom telescope, all the while designing vibration isolation devices that would only be installed ona spacecraft that didn’t officially exist.
Fortunately, the telescope’s defenders were able to rally in Congress and secure enough bipartisan support to kill the proposed budget cuts and formally fund the telescope’s transition into preliminary design phase in April.
Meanwhile, the telescope’s namesake, Dr.
Nancy Grace Roman (the Mother of Hubble and NASA’s first chief of astronomy) passed away in December at the ripe old age of 93, leaving behind a legacy which the telescope’s project office staffvowed to uphold in her honor.
2019
The telescope’s trials against the US government’s budgetary policies were far from over, however, as 2019 brought with it another presidential cancellation attempt.
While the telescope’s defenders once again thwarted the White House’s attempts to gut the program’s funding with an eye-popping short-term budget extension, engineers working in clean rooms encountered a major manufacturing obstacle while attempting to produce the physical heart and soul of the Wide Field Instrument.
The construction of the 18 massive near-infrared detectors faced a prohibitively low yield due to the painstaking process necessary to manufacture them.
With an exquisitely detailed chemical composition needed to properly convert light into an electrical signal, it was easy for even the smallest impurity to render a detector useless.
As a result, NASA partnered with Teledyne Scientific and Imaging to find a way to alter the chemical makeup of the production process in order to make the fabrication of these detectors more robust, while still maintaining the quality needed for the detectors to meet the mission’s demanding requirements.
This work, along with modifications to the sensor design, allowed production of qualified flight detectors to begin.
At the same time, data management experts analyzing the system requirements for the Wide Field Camera were stunned to find that it would generate an astonishing 1.4 terabytes of data each and every day.
This was far too much for the spacecraft data system to handle, and would overwhelm the existing downlink capabilities, causing vast amounts of valuable data to go unretrieved.
To resolve this crisis, engineers upgraded the spacecraft data management system and downlinked all of the telescope’s data using a high-capacity solid-state recorder, while simultaneously replacing the spacecraft’s radio with an ultra-high-gain antenna operating in Ka Band.
As a result, the telescope could now reliably send its daily data cache to waiting ground stations without disrupting its delicate observations.
With these final hurdles to the telescope’s construction cleared, the project team was finally able to complete the mammoth Project-level Preliminary Design Review on November 1, 2019.
An independent review board found the project to be well managed and on track for a timely launch within the 3.2 billion budget.
This allowed the telescope to formally exit its formulation phase and officially enter its final design and fabrication stage.
Thank you for watching,
Astrokid out
