For more than 20 years, astronauts on the International Space Station (ISS) have conducted thousands of scientific experiments in what is probably one of the coolest laboratories in the universe.
Now, a new batch of experiments has arrived at the orbiting lab, tackling topics like 3D bioprinting, plant adaptation and even fertility in space.
Here’s a look at some of the experiments sent on Northrop Grumman’s latest resupply mission for NASA, which arrived at the ISS on Wednesday.
Study of human fertility
Could humans one day inhabit space? It’s still a pretty far-fetched scenario, but to prepare for that possibility, scientists are studying what spending long amounts of time in reduced gravity might do to our fertility.
As part of the OVOSPACE research, which is sponsored by NASA and the Italian Space Agency (ASI), researchers are studying how microgravity influences ovarian cells.
They’ve sent bovine ovarian cells to the ISS to see how the development of those cells might be affected by being in space, as part of research they say could also lead to improved fertility treatments on earth.
Living for extended periods of time in the reduced gravity of the Moon or Mars could affect fertility, explains lead researcher Mariano Bizzarri, from the department of experimental medicine at Sapienza University of Rome.
“This threatens the goal of establishing permanent or extended settlements beyond Earth,” he said in a statement.
“Dysregulation of reproductive functions can also pose additional health risks,” he added.
The research results could improve our understanding of egg development and identify treatments to protect human reproductive potential on future space missions, Bizzarri said.
“This research could also support the development of treatments to improve or restore the fertility of people on Earth.”
3D printing of human tissue in space
Doctors have long dreamed of being able to 3D print organs on demand, something researchers hope microgravity can facilitate.
However, printing small, complex structures found inside human organs, such as capillary structures, has proven difficult to achieve in Earth’s gravitational environment, say researchers at the BioFabrication Facility, a 3D bioprinter.
As such, they hope that printing organ-like tissues in microgravity could act as a stepping stone to making whole human organs in space.
In 2019, the BioFabrication Facility successfully printed a partial human knee meniscus as well as human heart cells during its first trip into space.
An upgraded version of the 3D printer will make knee cartilage tissue aboard the ISS, using bioinks and cells to see if microgravity printing can produce tissue samples of a higher quality than those printed on Earth.
How plants adapt to space
Another experiment aboard the ISS examines how plants adapt to space, in research that could one day lead to better food and water and air purification systems on future space missions.
As part of Plant Habitat-03 research, seeds produced by plants grown in space are returned to Earth, processed and returned to space. Researchers are studying whether this gives an adaptive advantage to the next generation.
Plants exposed to spaceflight undergo changes that involve adding extra information to their DNA, which regulates how genes are turned on or off, but does not change the sequence of the DNA itself. This process is called epigenetic change, the researchers explain.
They want to find out if these adaptations in one generation of plants grown in space can be transferred to the next generation.
“This could provide information on how to grow repeated generations of crops to provide food and other services on future space missions,” they said.
The results could also help develop better strategies for adapting crops to sparsely populated habitats here on Earth.
First satellites of Uganda and Zimbabwe
Parallel to these experiments, the first satellites from Uganda and Zimbabwe have also arrived at the ISS.
CubeSats (essentially mini cube-shaped satellites) developed by students in Uganda, Zimbabwe and Japan will collect data about Earth that can be applied to their home countries.
The satellites were developed as part of a cross-border university project that allows students from developing countries to gain hands-on experience in developing satellites.
Studying dangerous mudslides
The space will also help scientists study dangerous mudflows, particularly the catastrophic ones that can occur after a wildfire.
When a wildfire burns plants, the burned chemicals create a thin layer of soil that repels rainwater, researchers say.
The rain then erodes the soil, and this can turn into catastrophic mudslides consisting of sand, water and trapped air, carrying heavy rocks and debris downward.
“Gravity plays a crucial role in the process by driving air up and out of the mix and particles down to the bottom of the water,” said lead researcher Ingrid Tomac, assistant professor in the department of structural engineering from the University of California at San Diego.
“Removing gravity, therefore, could provide insight into the dynamics of the internal structure of these sand-water-air mixtures and a baseline for their behavior.”
ISS researchers will examine a slurry of air, water and sand in microgravity to better understand the properties of these dangerous mudflows, and hopefully help us better predict and model these events.