The spacey part of the Gilroy lab has moved to Florida for a while as we gear up for the launch of APEX-05 (Advanced Plant EXperiment-05), our latest experiment to go to the International Space Station (ISS). It’s the third experiment in our Test Of Arabidopsis Space Transcriptome series (TOAST III). The goal of the experiment is to test how the reduced access to oxygen induced by the weightless environment of space affects how plants grow on orbit. The ISS has an atmosphere like that on Earth with ~21% O2, so where does the low oxygen effect come from? When there is no gravity, there is no buoyancy; a hot air balloon floats in the air because it is buoyant, i.e., as the hot air inside the balloon expands it “weighs less” than the surrounding colder air and so it floats upwards. In the weightlessness of spaceflight, weighing less no longer counts and so buoyancy disappears. When there is no buoyancy, there is no longer any buoyancy-driven convection in gases (warm gases rising and causing the mixing in of other gases from below). On Earth, when living things like plants and people use up oxygen when they breathe, this convective mixing replaces the lost gases. With no such mixing in space, organisms can use up their local oxygen and go into a state of oxygen deprivation called hypoxia. For TOASTIII we will be growing plants on the ISS, freezing them, and then bringing them back to Earth to analyze the levels of all their genes (their transcriptome) to see if we can observe patterns of low oxygen stress to try to understand how this loss of convective oxygen supply alters plant growth in space.
The second part of our analysis is using a microscope on the ISS, called the Light Microscopy Module (LMM). We plan to look at plants that we have engineered with a visual reporter of a response to stress. We should be able to literally see which cells are undergoing stress responses such as reduced access to oxygen as they occur in real time. The Light Microscopy Module is a new piece of hardware for us and it has also recently undergone a major upgrade with a new camera and imaging setup being installed on Station. We were therefore really excited to be able to visit NASA Glenn Research Center in Cleveland earlier in the week on the way down to Kennedy Space Center to spend a day getting familiar with the instrument (it is run out of Glenn) and especially meeting the amazing team that runs it. As you can imagine remotely running a microscope traveling at 17,000 miles per hour (that’s how fast the ISS is orbiting!) and ~250 miles above your head plus getting the resulting images down is no small feat. The LMM team at Glenn, including Tibor, Andrea, Amber and Lou, are a super team to work with and we’re looking forward to heading out for Glenn in a few weeks when we start our on orbit LMM operations for real. More to come on that adventure as it happens.
After visiting Glenn, two of our team (Sarah Swanson and Simon Gilroy) traveled on to Florida, arriving at Kennedy Space Center (KSC) on Wednesday Nov 29th. From then until now, things have been simultaneously hectic and on hold. On arriving, we immediately set about unpacking our gear, testing the preflight equipment and generally getting set up for the experiment. That’s a couple of day’s worth of work but we were on schedule, so no worries about hitting the December 4th launch target. We are flying on SpaceX-13 and as you come to expect for any flight there have been some launch delays; this is rocket science after all. Our launch had been pushed back from September 13th to November 1st and then to Dec 4th and so setting up from November 29th gave us exactly the time needed to be ready to hand over our samples the requisite 2 days before launch. However, launch has now been pushed back again to “No Earlier Than” (NET) December 8th. The good thing is we get a few more days to set up (always a help) and time to work on some other projects at Kennedy such as using the LMM setup there to analyze our samples further. The third member of our team, Richard Barker, was able to change his travel plans and arrived yesterday. If there’s one thing you learn when doing flight experiments, plan meticulously but don’t get too attached to those travel dates. So we are in set up mode at the moment, with fingers firmly crossed that launch will occur on the 8th. More to come as we move in on launch day.