We’ve just received confirmation that the SpaceX 2 (SpX-2) launch is now officially scheduled for March 1, 2013. NASA has entered it on its Consolidated Launch Schedule web site.
SpX-2 is the second NASA-contracted payload inside SpaceX’s Dragon capsule. The first was a space station resupply mission in October 2012, and the third is slated for October 2013. SpX-2 will carry the two BRIC-17 experiments up to the space station, including our Arabidopsis from the Gilroy Lab at the University of Wisconsin – Madison and plant cell cultures from the Paul Lab at the University of Florida – Gainesville.
Last month, the BRIC-17 teams completed their Payload Verification Test (PVT) at the Kennedy Space Center in Florida. This was a “dry run” of the experiment as it would be set up and run for the actual launch. Given our germination problems during the SVT (Science Verification Test) in October, we wanted to be sure that our revised method worked perfectly.
The method with perfect success during the PVT, and so the method we will use for our space flown experiment, was placing the seeds directly on Phytagel. Phytagel is a nutrient-containing “jello-like” material that we pour as a warm liquid into the bottom of the petri plate. Once it is cool, it forms a firm surface on which we place surface-sterilized seeds.
For our experiment, we will put 64 seeds in an 8×8 grid on the Phytagel surface in a total of ten 60mm petri plates. This is the science that will be loaded into the space hardware (PDFU inside BRICs) by NASA specialists and stored at 4 degrees C until launch. The cool temperature will prevent germination until the start of the experiment in microgravity. For launch, our BRICs will be placed in a cold bag to maintain the cool temperature while on board the Dragon capsule en route to the ISS. Once on the ISS, the astronauts will place our BRICs at ambient temperature and the experiment begins. This warmer temperature (20-22 deg C) will allow germination and seedling growth in microgravity.
Following 8 days of growth, the astronauts will inject RNAlater solution to fix our microgravity-grown seedlings, then the BRIC will be placed in the freezer. After our experiment returns to Earth, the NASA team will open our BRIC to retrieve our samples (deintegration). The plants should look similar to our plants grown during the PVT, shown below.
The seedlings are “etiolated,” which means that they are grown in the dark. Dark-grown Arabidopsis has a long shoot (hypocotyl) and relatively short root. The leaves do not expand or turn green. The lead scientist on our project, Won-Gyu Choi, isolated RNA from the shoot and the root of our PVT plants. The RNA contains transcripts of the genes that are expressed in the plant at the end of the 8 days of growth; the RNA expression provides a snapshot of how the plant was regulating its gene expression in response to its environment. For example, from Earth-based research we know what genes show enhanced expression during low oxygen stress in plants. We will compare the expression of these anoxia-induced genes in the space-grown material to the control plants we grow in the Orbial Environmental Simulator at the Kennedy Space Center.
This morning, our PVT results were carefully examined by the NASA team in charge of the BRIC projects, and any risk factors thoroughly considered. This is called the Phase C Review. Following extensive review, the BRIC-17 projects were given NASA’s official stamp of approval for flight on SpX-2. Yay!
Now, all we can do is wait until the end of February 2013, when the Gilroy Lab team will again travel to Kennedy Space Center to prepare our samples to be loaded into the Dragon capusule for the March 1 launch of SpaceX-2.