Just 38 hours after leaving Earth, SpaceX’s CRS-14 Dragon completed her rendezvous with the International Space Station. Grapple occurred 06:40 EDT (10:40 UTC) to be followed by berthing to Node-2 Harmony’s nadir port at around 09:00 EDT (13:00 UTC). Arriving with the flight-proven Dragon is a wealth of scientific experiments that will add to the 280 investigations slated for the current Expedition 55 and 56 increments.
CRS-14 Dragon science arriving at Station:
Following a flawless launch Monday, 2 April at 16:30:38 EDT, Dragon successfully reached orbit and began its day and a half long chase of the International Space Station. The orbital ballet included hundreds to thousands of thruster firings of Dragon to precisely tweak its attitude for communications and checkout purposes, with only 12 of those burns being major course corrections to align the craft with the Station.
A detailed approach timeline for Dragon CRS-14 can be found on L2, here.
CRS-14 begins as a flight-proven Falcon 9 lifts a flight-proven Dragon away from SLC-40 at the Cape Canaveral Air Force Station, FL. (Credit: Brady Kenniston for NSF/L2)
Once safely berthed to Station, the ISS crew will begin the month-long task of unloading Dragon of all its supplies and experiments.
Comparative Real-time Metabolic Activity Tracing for Improved Therapeutic Assessment Screening Panels:
This experiment, which seeks to illuminate the effects of microgravity on the metabolic impact of therapeutics, comes from 490 Biotech – a startup-level biotechnology company from Tennessee that’s developing the next generation of bioluminescent imaging technologies.
Specifically, this experiment will evaluate the effectiveness of auto-bioluminescent human tissue culture as a tool for streamlining microgravity-based drug discovery assays (testing of a metal or ore to determine its ingredients and quality). “When most people think about bioluminescence, [they] think about fireflies blinking in a field in the middle of summer,” said Dr. Dan Close of 490 Biotech. “Unfortunately the current iteration of bioluminescent technologies, just like fireflies, are sort of one and done. They blink, you get a little bit of information, and then you have to start all over again.”
To solve this problem, 490 Biotech has developed a new technology called auto-bioluminescence. “This is basically a big step forward in bioluminescent imaging where instead of intermittent snapshots of data acquisition, we can continuously monitor any living cell, whether that’s a bacterium, a yeast, a human cell culture, or a small animal model, and we can track their metabolic activity in real life,” said Dr. Close.
For this experiment, the light emitted by the cells is used to judge the cells’ overall health – with healthy cells glowing bright and dead cells not glowing at all. While this is already being done here on Earth, the microgravity environment is actually a better medium in which to study human cells because, as Dr. Close relates, “somewhat ironically, when you grow these types of human cells in a dish, if you grow them in microgravity their physiology, the way they behave, is actually more similar to how they behave in the body then if you grow them in a lab on Earth.”
This is because cells grown in dishes on Earth spread out in two dimensional instead of three dimensional growth patterns as happens in the body. In space, the cells grown in dishes naturally grow in three dimensional patterns, and this makes it easier to study the effects of therapeutics because scientists are studying the cells from a natural growth state.
“Companies are spending lots of money and lots of exotic resources trying to encourage [this 3D growth] here in normal gravity, and those three dimensional structures are impacted by those strange technologies that can have adverse effects on the way the cells grow, which in turn makes it more difficult to predict the efficacy of potential new therapeutic compounds,” said Dr. Close.
A self-promoting example of auto-bioluminescent human cells at various health states. The brightly glowing cells are healthier than the dimmer glowing cells. (Credit: 490 Biotech)
The experiment will see the cells launched to the ISS grow in space and then be treated with known therapeutic compounds – with a parallel ground experiment doing the same. This will “demonstrate the difference in the effectiveness of these therapeutic compounds between Low Earth Orbit and down on Earth by using a combination of compounds that were approved for usage within human subjects and those that failed at the clinical testing level,” noted Dr. Close.
“Our hope is that we can demonstrate that taking advantage of the more natural human physiology that occurs within these cells during growth on the International Space Station can provide a way for pharmaceutical companies to do [part of their drug] screenings at low cost in Low Earth Orbit and get better information about the safety and potential functionality of these new drug compounds.”
In short, this experiment could potentially lead to more effective and less expensive drug compounds for use here on Earth.
Atmosphere-Space Interaction Monitor:
Developed by Dr. Torsten Neubert of the National Space Institute at the Technical University of Denmark, the Atmosphere-Space Interaction Monitor (ASIM) is an external payload that will be mounted for at least two full years on the outside of the European Space Agency’s (ESA’s) Columbus module.
Specifically, ASIM will be looking for “gigantic lightning shooting up from thunderstorm clouds up to the edge of space and flashes of high energy radiation called terrestrial gamma-ray flashes that come from thunderstorm clouds,” said Dr. Neubert. In other words, ASIM is designed to look at upper-atmospheric lightning, or transient luminous events, that occur well above the altitudes of normal lightning and storm clouds.
“The things we’re looking for are relatively newly discovered. We’ve known of them for 15 to 20 years,” noted Dr. Neubert. ASIM will provide the most comprehensive global survey of transient luminous events and terrestrial gamma-ray flashes in the region of the atmosphere within and above severe thunderstorms to help determine their physics and how they relate to lightning.
The experiment will also quantify the effects of gravity waves on the mesosphere, study high-altitude cloud formation, and determine the characteristics of thunderstorms that make them effective in the perturbation of the high-altitude atmosphere. Moreover, ASIM will help improve our understanding of the effect of dust storms, pollutants from large cities, forest fires, and volcanoes on cloud formation and electrification, as well as the intensification of hurricanes and that intensification’s relation to eye-wall lightning activity.
ASIM could also lead to improvements in atmospheric models and predictions related to climatology and meteorology.
Veggie PONDS:
Following the recent success in growing food – specifically, lettuce – aboard the International Space Station, a new experiment designed to increase the efficiency of this process is included in the CRS-14 Dragon cargo manifest.
A veggie PONDS ground unit is tested at the Kennedy Space Center, FL. A similar version is onboard CRS-14 Dragon for testing on the International Space Station. (Credit: NASA)
Called Veggie PONDS (Passive Orbital Nutrient Delivery System), the experiment uses a newly developed passive nutrient delivery system and the Veggie plant growth facility already aboard the Station to cultivate lettuce and mizuna greens, which are to be harvested on-orbit and consumed – with some samples saved for return to Earth for analysis.
“We’ve spent the last two years developing prototypes here at Kennedy Space Center for this new way of growing food in space,” said Dr. Howard Levine, Chief Scientist, International Space Station Research Office. The Veggie PONDS are replacing the current veggie units on the ISS, which – while successful – led to irregularities in growth uniformity of the plants as well as problems with seed germination.
Veggie PONDS work by using capillary action to bring water from a reservoir to the planet reservoir, where a substrate and slow-release fertilizer pellets then allow seeds to germinate. The new veggie PONDS are made from Tupperware – the same brand found in most households – and are roughly the same weight as the veggie units currently on the Station.
A total of seven veggie PONDS are included on the CRS-14 Dragon, with six more to follow next month on the OA-9E mission of Orbital ATK’s Cygnus resupply vehicle. Moreover, while the original veggie units were designed for one-time use, the new veggie PONDS are designed to be reused.
Dr. Levine holds a model of a Tupperware(™) veggie PONDS unit during a pre-launch briefing for the CRS-14 resupply mission to the International Space Station. (Credit: Brady Kenniston for NSF/L2)
“One big thing is that these are reusable,” said Dr. Levine “The [veggie units] we currently have up there, it’s a one time use and then they get tossed into a Progress. They burn up. [The veggie PONDS] can be one time use or we can bring them back. And in this experiment, we’re bringing them back. So we hope to refurbish them and reuse them. You could, we believe, refurbish them on the International Space Station for reuse, too.”
Remove Debris:
This external experiment from NanoRacks will examine new processes for removing debris from orbit, demonstrating an approach to reducing the risks presented by space debris or “space junk”.
Removing large pieces of debris from orbit could greatly reduce the risk of mission-ending and life-threatening collisions. While such collisions and ISS Collision Avoidance (COLA) maneuvers are rare, they do occur. On 10 February 2009, the first hypervelocity collision of two satellites occurred when operational Iridium-33 and two-years deactivated Russian Kosmos-2251 collided with each other at 26,170 mph.
Two years later, on 2 April 2011, the ISS had to perform a COLA maneuver via the ESA’s Automated Transfer Vehicle -2 that was docked to the ISS at the time to ensure a large enough “miss” probability (greater than 1 in 10,000) with a debris fragment from Kosmos-2251 as it descended toward a destructive reentry to Earth’s atmosphere.
The initial debris field from Iridium-33 and Kosmos-2251 in the first few minutes after collision. (Credit: Courtesy of Analytical Graphics, Inc. – www.agi.com)
Now, NanoRacks-Remove Debris will demonstrate a capability of using a 3D camera to map the location and speed of debris and deploy a net to capture and de-orbit simulated debris up to 1 meter (m) in size. Specifically, Remove Debris will examine two way of capturing and safely de-orbiting debris.
One such method involves catching debris in a net. According to NASA, “The net demonstration deploys a net that captures simulated debris of up to 1 m in size. Once the net captures the target, both the target and the net de-orbit very quickly” due to increased drag on the debris created by the net.
Remove Debris will also test the ability to harpoon pieces of debris. The harpoon is attached to a tether to provide assessment for its flight and operation.
Overall, the experiment will use a microsatellite test-bed that carries the Active Debris Removal payloads as well as two deployable nanosatellites (CubeSats). “Through a series of operations, one of the nanosatellites is ejected, re-captured, and de-orbited,” notes NASA. The other CubeSat is the target of the visual based navigation experiment. Once the demonstrations are completed, the microsatellites will be rapidly de-orbited using a drag sail.
In addition to making spaceflight safer for spacecraft and astronauts, developing the ability to safely and quickly de-orbit large pieces of debris or large, non-operational spacecraft could prove vital to space-based services like GPS navigation and terrestrial cell phone communication.
With recent events in mind, this technology could also help safely de-orbit future, large satellites like Tiangong-1 into the ocean, avoiding the prolonged and great uncertainty that preceded the Chinese station’s fall from orbit – a fall that posed a potential – albeit, small – risk to land before its eventual and coincidental reentry over the southern Pacific Ocean, ironically quite near the spacecraft graveyard where most spacecraft destructive reentries are targeted toward.
Returning cargo/experiments:
Among the cargo that will return next month when CRS-14 Dragon concludes its ISS stay and splashes down in the Pacific Ocean for recovery and potential reuse include several rodents from the Rodent Research experiment launched in December 2017 on CRS-13 as well as Robonaut-2.
Robonaut-2 is a humanoid robotic development project by the Dextrous Robotics Laboratory at the Johnson Space Center that launched to the Space Station in February 2011 aboard STS-133, the final flight of Space Shuttle Discovery. Since then, Robonaut-2 has performed various tasks to assist Station crews with their daily workloads and has been used to perform cleaning operations – allowing Station schedulers to free up crew time for other, more important tasks.
When launched, there were no plans to return Robonaut-2 to Earth, but when it stopped powering up on orbit and crew troubleshooting could not fix the issue, NASA turned to their ground Robonaut units for answers.
“Engineers have looked at why Robonaut wasn’t able to power up on board,” said Pete Hasbrook, associate program scientist for the International Space Station Program. “Through the other Robonaut units on the ground, they figured out that there’s something in the electrical system, some kind of a short that’s unique to the Robonaut on the Station. So they are pretty confident that when they get it back and they dig into it, they’ll be able to repair it fairly quickly.”
Once repaired, NASA anticipates manifesting Robonaut-2 on a future Commercial Resupply Services mission in about a year’s time. While Robonaut-2 is coming back on a Dragon, it does not necessarily have to re-launch on one as Orbital ATK’s Cygnus craft is also be available in the first half of next year to return the mechanical astro-man to Station.