Science without gravity at the ISS
In two decades orbiting the Earth the International Space Station has become a cutting-edge cosmic laboratory, with astronauts researching everything from black holes to disease and even gardening in microgravity.
The ISS, which orbits about 250 miles above Earth, is as large as a football field inside and divided up like a beehive into spaces where the crew can carry out experiments with guidance from researchers on the ground.
Often, the astronauts are also the experimental animals. More than 3,000 scientific tests have been carried out at the ISS since its manned missions began in 2000.
“From a science perspective, there have been some major discoveries,” said Robert Pearlman, space historian and co-author of “Space Stations: The Art, Science, and Reality of Working in Space”. The latest mission — named “Alpha” after Alpha Centauri, the closest star system to our own — will be no exception.
‘MINI-BRAINS’
On Thursday, US astronauts Shane Kimbrough and Megan Mcarthur, the Japan Aerospace Exploration Agency’s Akihiko Hoshide and the European Space Agency’s Thomas Pesquet were to blast off for the ISS aboard the Spacex mission Crew-2.
They are likely to be busy.
Alongside work to maintain the space station itself, around a hundred experiments are in the diary for their six-month mission.
These include an acoustic technique using ultrasonic waves to move and manipulate objects or liquids without touching them.
France’s Pesquet has said his favourite planned research is a study examining the effects of weightlessness on brain organoids — mini brains created using stem cell technology.
Scientists hope this research can eventually help space agencies prepare for distant space missions which will expose crews to the rigours of space for long periods of time, and even help fight brain disease on Earth.
“It really sounds like science fiction to me,” joked Pesquet, an aerospace engineer.
There is ongoing research into what are known as “tissue chips” — small models of human organs that are made up of different types of cells and used to study things like ageing in the immune system, kidney function and muscle loss.
“We don’t fully understand why, but in microgravity, cell-to-cell communication works differently than it does in a cell culture flask on Earth,” said Liz Warren, senior programme director at the ISS US National Laboratory, adding cells also gather together differently.
“These features allow cells to behave more like they do when inside the body. Thus, microgravity appears to provide a unique opportunity for tissue engineering.”
Another important element of the mission is upgrading the station’s solar power system by installing new compact panels that roll open like a huge yoga mat.
Crew-2’s launch day coincides with Earth Day, and by the time the crew returns they will have also contributed to environmental research by taking 1.5 million images of phenomena like artificial lighting at night, algal blooms, and the breakup of Antarctic ice shelves.
From a science perspective, there have been some major discoveries since its manned missions began in 2000
ROBERT PEARLMAN Space historian