In February 2017, a SpaceX Falcon 9 rocket is lifted through low clouds and shooting a Dragon capsule against orbit.…
In February 2017, a SpaceX Falcon 9 rocket is lifted through low clouds and shooting a Dragon capsule against orbit. Among spare parts and food, an important part of scientific cargo, called SAGE III, moved upward. Once installed at the International Space Station, SAGE will return and measure ozone molecules and aerosols in the Earth’s atmosphere. Its older siblings (SAGEs I and II) had revealed both the growth of the gaping ozone hole and, after people decided to stop spraying Freon everywhere, its subsequent recovery.
The third children then had a lot to live up to. Like its environmentally conscious predecessors, SAGE III is highly sensitive. Because uncontaminated conditions are needed to function optimally, it contains pollutants who keep an eye on how and how their environment can interfere with their measurements. These sensors soon came to fruition: When the next three dragons docked at the space station, in the following months, SAGE experienced unexplained nails in contamination. Something on these dragons were release-releasing molecules beyond the expected, and perhaps the acceptable levels. And these molecules stick to SAGE.
Bleeding, on earthly conditions, is what makes a new car smell like a new car. “There are volatile chemicals in the new materials that migrate through the material to the surface,” said Alan Tribble, author of the Fundamentals of Contamination Control . You smell arbitrary seat ingredients, in other words. [1
9659002] Outgassing also builds up like an oily film inside the window of your new car or on the outside of your space station. This dirt is usually a problem for instruments that measure light, but it can also reduce the efficiency of the solar panels and can make the surfaces hotter than they should be. To avoid everything, engineers build Space Station add-ons and satellites in clean rooms, use only pre-qualified materials, disregard pre-launch contamination and set strict limits for how much proverbial new car smells a craft can release. “It’s an intensive process and is considered extremely critical,” says Meg Abraham of Aerospace Corporation, who consults a number of space projects. “Everybody thinks about this.”
But the pre-planning does not always work: When the astronauts took some early Hubble Space Telescope instruments back to earth, they found, for example, that the telescope’s $ 1.5 billion body, which would have cost $ 2.89 billion in 2018 dollars, had sprayed enough molecules to them to greatly impair their ability to detect ultraviolet light – one of the telescope’s primary capacity.
NASA has handled such dirt for decades, but the dirt has so far largely come from the agency’s own creations. The dragon, however, is different. It belongs to SpaceX. Today, the company is planning to launch another Dragon capsule full of cargo, and perhaps blow out pollutants, to the space station. This launch will be the company’s sixteenth commercial resupply mission.
As NASA relieves the activities of private companies like SpaceX, Orbital ATK (now part of Northrop Grumman) and Boeing, it has to react when their children abuse. And that’s a big deal: New ISS instruments tell us how our planet and universe around it works at prices in tens of millions of years of years of development timelines. With these efforts, it is the last thing scientists, engineers and citizens want for a private company’s capsule to measure measurements.
SAGE III went to Space Station aboard SpaceX’s tenth resupply mission for NASA, as part of a SpaceX contract to make the agency’s local deliveries. As soon as SAGE was on board, its contaminating catch crystals recorded Dragon’s excessive outgassing.
These crystals are not of the healing variety (spoiler alert: none are) but are instead “thermoelectric quartz crystal microbalances”. Each of SAGE’s eight such sensors has two twin crystals, and in collaboration they do the two “pollution monitoring packages”. These crystals swing at a certain frequency, which matches their masses. If a crystal becomes more massive, say a spacecraft sends new-car-smell-its frequency changes.
When the twin crystals begin on their mission, they are exactly the same. But at the space station, one of the two is exposed to the environment, while others are protected. It is typical of twin studies in psychology. By measuring the difference in twinning rates, researchers can determine how much pollution is deposited on the exposed, even if it does not reveal the nature of all layers.
After the eleventh dragon, a contingency monitoring package’s frequency steadily arrived, according to a presentation published on September 1, to NASA’s Technical Reports Server, a database of documents created or funded by the Agency. The data was remarkable because NASA sets limits for sensitive surface contamination, which includes some of the more sensitive parts of ISS. The crystals in this case served as canaries, warning for potential damage to the exquisite instruments.
Results are preliminary, but Dragon may have deposited according to this presentation up to 21 times the permissible amount of contamination on a sensor. The crystals also changed significantly in frequency when the next dragon was docked and the report estimates that this assignment may have left up to 32 times the regular amount of extras on a sensor.
The presentation was compiled by the Space Mill team, a NASA and Boeing collaboration dedicated to understanding how the hard realities in space move with instruments and people. With the difficult tasks in hand, the space environment people designed an experiment to find out what’s happening. Perhaps they thought the problem was the sunrise or the material on the outside of the capsule. To limit the list of suspects, during the thirteenth Dragon flight, the engineers placed the sunrays so that their edges met the space station. If the panels exhaust gas, they would not exhaust at the spacecraft. The mass would build up on the crystals slower and keep the frequency relatively constant.
But that was not what happened. As the matrix was tilted, the frequencies of the crystals continued to tip up. The drinking capsule itself seemed to be the problem – a problem that got worse the more sunbeam shine on it. During this thirteenth mission, a sensor may have been sprayed 73 times more than allowed during a stay. And for the month or so, as Dragon was docked at the Station, two of the sensors detected more pollution than allowed – in total, from the station – for a whole year .
Among the space supplies exposed to the capsule’s gasification is the American Laboratory Science window, a porthole through which astronauts and instruments can look out on earth. On the more scientific side, there is CATS, an instrument that measures smoke, pollution, dust and other particles in the planet’s atmosphere. In total, seven sensitive areas or instruments on ISS, including SAGE, may be polluted across the border.
“NASA has communicated with the station’s payload community its results, and payload developers have also replied that their instruments have not had any impact or they have taken precautions to mitigate the impact on their science,” said Space Environments in a statement. The SAGE III team closes the “pollution door of the instrument” as a standard operating procedure when any spacecraft visits protects its optical instrument, although the resulting measurements are not as sensitive.
And at least SAGE III, whose optic is “Sensitive to Molecular Pollution Decomposition” knows when it needs to look up. The SAGE III team knows only the exact levels because it carries pollutants that did not exist at the station earlier.
However, SpaceX looks at its ingredients. “SpaceX has reviewed all external materials choices on Dragon and works with suppliers to u tveckla low degassing variants of qualified materials to improve the molecular deposition rate, “said the company, adding that NASA approved all materials used in the first Dragon design.
Antonius de Rooij, author of Space Materials Database, believes that the color of the capsule is the likely problem. For one, he says, “the white painted surface is very big, which means that even low emissions can have a high pollution effect.”
He is also curious about why the Space Environment Act took into account solar heat and radiation, but did not consider the human or earthly factors. “Is the color applied correctly? Is it tempered?” He says. “I was a little surprised that these points were not mentioned.” The color will not appear as advertised if the surface is turned on is not ultraclean, or if the moisture while it is dry is not Goldilock-correct. Maybe the coloring steps were not exactly the same. “This batch variant may be the reason for different degassing and different optical properties between batches,” he says.
Or the surface could have been tainted after the color cured. This contamination can lead to more pollution. While the exact color of these three dragon missions is not public information, at least one previous mission used one called Alion Z-93c55, a variant of Alion Z-93. If Alion Z-93 gets infected after curing, it is prone to degradation when UV rays hit it, a phenomenon documented back in 1971. It absorbs more sunlight, gets hotter than expected and expels more. “I wonder why they did not mention this in their report,” said Rooij.
Part of the problem here, however, is NASA’s reluctance to talk about both the problem and the plans to fix it. The presentation, shared by the Workload Integration Working Group, gathered in April, was approved for unclassified and unlimited publication and was placed on NASA’s Technical Reporting Server in early September. I asked for an interview about it on September 25th. The next day the presentation was gone. “The record information page you tried to access can not be found on this server,” says the page now. I asked about the dead link, and more than three weeks later, I received an answer: “The document is under review,” wrote Meagan Storey, NASA’s scientific and technical information program, “and we recommend that you make a FOIA request for the item.”  Statistically, it is probably a losing prospect. If we use FOIA requests as a proxy for transparency, NASA is one of the government’s most hidden agencies. It denied more FOIA requests in percent by 2017 than the Department of Defense, the Securities and Exchange Commission, the Department of Energy, the Environmental Protection Agency, the Nuclear Regulatory Commission and the Office of Director of National Intelligence, organizations that largely have more to protect than the nation’s space agency. To be fair to NASA, which denied 71 percent of the requests, the CIA denied 78 percent.
Last month, before I had seen this report, I knew something was up. I had seen a previous document that said: “The dragonic tribe particulate background has not been marked, but emissions have been observed.” And then I had asked NASA’s SAGE III team, knowing that output could affect their instrument – if they had changed some of their plans due to concerns about Dragon. “No negative pollution effects or concerns about SAGE III science”, they responded via email. “Nothing to put beyond.”
As I learned from the case of the missing presentation and three mission values of measurements that a lot of teams had taken, there was a lot to add beyond that.
To be cagey about pollution problems, the Office protects not only itself but also its private profit partner, SpaceX, whose capsule, in turn, affects the ISS instruments supported by federal funds.
The lack of transparency will soon become more relevant when private companies begin shuttling not only astronauts in the Ce-cream and atmospheric instruments but also people back and forth from space, as part of the Agency’s commercial crew program. Another iteration of Dragon will take some of the future astronauts up. “SpaceX uses data to improve its Dragon 2 personnel and trucks,” says the statement of space environmental law.
Today’s pollution problems can not cause major problems, but if there was a big problem with tomorrow’s dragon or another company’s operator, it suggests that it can be prepared behind closed water doors or foggy windows.