October 20, 2021

I, Science

The science magazine of Imperial College

Soyuz rocket

The Soyuz MS-02 rocket launch on Wednesday 19th October in Kazakhstan. A very similar rocket took Tim Peake and Time Ronke up to the ISS in 2015 (Source: NASA/Joel Kowsky)

It’s been a big week for space – with a mars rover crash landing, a successful launch of three new astronauts to join the team on the International Space Station and the end of their UK tour for British astronaut Tim Peake and US astronaut Tim Kopra.

2 astronauts

Tim Peake, Yuri Malenchenko and Tim Ronke formed the crew of expedition 46 that left for the ISS in December 2015 (Source: ESA)

Speaking at the Royal Albert Hall in London on Wednesday night, Peake and Kopra answered the big questions about life on the International Space Station (ISS). How does it feel to be in space? Did you see any aliens? And most importantly – what do astronauts actually do up there?
As well as exercising at least two hours a day and cleaning the space station on Saturdays, a substantial amount of an astronaut’s time up in the ISS is dedicated to conducting scientific experiments.

…so why conduct experiments in space?

In space, the effects of gravity are hardly felt at all. This ‘microgravity’ has interesting effects on the growth of living organisms, which forms the basis of a number of studies. Additionally, there is interest in understanding the effects of exposure to cosmic radiation, which we are shielded from on Earth, by our atmosphere. We know that high exposure to radiation can have extremely damaging effects on living things. More than four Sieverts of radiation, the equivalent to 1,000 chest x-rays at once, can kill you.

These are both reasons why so many of the experiments carried out on the ISS involve living things – mostly cells and organisms – but even the astronauts themselves! Tim Peake describes them as his favourite experiments, because “We’re the guinea pigs!”

astronaut showing a bubble

Tim Peake conducting experiments in his ‘Cosmic Classroom’ series while on board the ISS with a bubble of water. Outreach activities by the Principia mission reached over 1 million school children during Tim’s time in space. (Source: ESA)

What are the coolest space experiments and their results?

Searching for Aliens
So-called Aerogels, described as essentially large petri dishes, are currently attached to the outside of the ISS. They are collecting micro-meteorites from space and have identified organic material with origins outside our planet – potential signs of alien life!

The crew of Apollo 11 did some of the first moon science, which involved not only collecting moon rocks, but also laying down seismometers to detect moonquakes in the same way we measure earthquakes here at home. These readings helped us to understand that the moon has a crust, a mantle, and a core – just like Earth.

Becoming space-men
“If there’s one thing I’ve learnt, it’s that we’re really good at adapting to our environment”, said Tim Kopra. An astronaut’s body will change quickly to adapt to living in space: their bones loose density, their immune system becomes supressed and even their heart and skin change to cope with the microgravity. This could be an issue when returning to earth, but the best news for the astronauts is that human adaptability works both ways. On their return to earth it only takes a few months for the effects to return to normal. The only exception concerns bone density, which takes about a year to recover.

Space bug evolution
Bacteria adapt quickly to space too. Some experiments conducted on the ISS have shown that space flight makes pathogens stronger and that bacterial growth is higher in space compared to samples on Earth. This is important for space flights, because life as an astronaut is so busy, that they have no time for sick days. Bacteria have demonstrated that space flight can change the activity of some genes. To test this further, they’re clipping different genes out of yeast bacteria and sending it up to the ISS to find out which genes best allow these astro-bugs to adapt.

Trees stay greener
Another big question relates to how plants are able to grow in microgravity. Astronauts carrying out tests on the ISS, found that seeds grew as they normally would on Earth, with the exception that there was a delay in the aging of leaves, which kept the leaves darker green for longer.

Satellite in space

The International Space Station (Source: NASA)

Liz Killen is studying for an MSc in Science Communication

Banner Image: ISS, NikoNomd