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Knit the Universe

A whole new kind of space craft!

We often liken spacetime to a fabric, but how can we bring this to life?

From left to right: the original image of GW Orionis, a rare triple-star system, the pattern, and then the finished knit.

We have converted amazing cutting-edge astrophysical images and findings (e.g. a gravitational wave ‘chirp’ or intersecting dusty discs around stars) into cute knitting patterns that can be completed in two to six hours. We call these our knit kits.

What is special about each kit is the story of the people and the science behind each one. Each completed knit kit, each square helps us tell the story of the fabric of the universe, and what we call spacetime.

Families at home, community knit and natter groups, scouts, guides, Duke of Edinburgh (DofE) participants, teachers and pupils looking for something creative and amazing to do during the long winter nights can (and should!) download the kits. With some knitting needles and a few bits of wool, you can knit your own patch of inspirational, spacetime science, learning skills along the way.

At the moment, we can’t be together, but we can share and show images of our squares on social media (@knittheuniverse on all platforms). You can knit a few, stitch them together and make a scarf that would make Doctor Who proud. Or knit many and make a throw or blanket (a DofE skills project perhaps?).

Later, when you can be together, you can gather up squares to make throws or blankets that you, your families, and your schools and community groups put together yourselves. We want to hear about them all on Twitter, Instagram, Facebook and TikTok.

Download the knit kits

Knit Kit 1 – A Rose in the Reaches

Level: experienced

In September 2020, scientists told the world that they had found an interesting star system. Using telescopes in Chile, called the Atacama Large Millimetre Array (ALMA), they had tracked this star system for more than 11 years.

Professor Stefan Kraus and his team in Exeter used these 11 years of measurement to work out the path that the three stars took orbiting each other. Then, once they knew how the stars moved, they used a set of equations that describe fluids (together known as hydrodynamic modelling) to calculate how gas and dust might move around the stars.

Download the knit kit (PDF, 203KB).

Read more about this discovery

Knit Kit 2 – Of Ripples and Rings

Level: intermediate

In September 2020, scientists told the world that they had found an interesting star system. Using telescopes in Chile, called the Atacama Large Millimetre Array (ALMA), they had tracked this star system for more than 11 years.

The ALMA telescopes don’t look what you might think telescopes look like – they’re a lot of satellite dishes. High in the Andes mountains in Chile, one of the driest places on Earth, you might find dishes pointing to the sky.

They span a huge area in the mountains – the two furthest dishes are about 16 km away!

Download the knit kit (PDF, 168KB).

Find out more about the telescopes that saw these rings and ripples

Knit Kit 3 – The First Chirp

Level: beginner

Have you ever been in the right place at the right time? Arriving to a party just in time for your favourite song? Well, the scientists at LIGO (it stands for the Laser Interferometer Gravitational-Wave Observatory) have the ultimate “just in time” story.

LIGO has two labs, both in the US; one in the north-west, and the other in the south-east. They started building both sites in the 1990s, and by 2010 they had done five years of searches without finding anything.

Both machines were shut down for five years for some big upgrades. In the same week that they were turned back on for their first search since the upgrades, a big gravitational wave – the very thing that they were looking for – passed through Earth!

Download the knit kit (PDF, 130KB) ​​

You can find out more about gravitational waves in Knit Kit 4: Wibbly Wobbly Timey Wimey (below), and read more about LIGO.

Knit Kit 4 – Wibbly Wobbly Timey Wimey

Level: experienced

Gravity brings things together – it’s one of the four main forces that describe the universe we live in. In 1916, a new theory came on the scene that made better predictions about how planets move around the sun.

The idea is called “general relativity” and treats space (and time) like a stretchy sheet that is bent by heavy objects. But this “sheet” idea adds a wrinkle – when something heavy moves around, it sends out ripples and waves across the sheet.

These ripples stretch space and time, meaning that as they pass through the Earth, the Earth gets (very, very) slightly smaller and wider in the peaks of the wave, and taller and thinner in the troughs of the wave. In 2015, scientists at the Laser Interferometer Gravitational-Wave Observatory (LIGO) detected these waves for the very first time!

They raced beams of light down two 4 km tubes. If a gravitational wave passed through the Earth, one tube would be shorter than the other. Light always moves at the same speed, so the light in the shorter tube would race back to the starting point (very, very) slightly earlier than the light in the longer tunnel.

Download the knit kit (PDF, 137KB)

Read more about gravitational waves.

Knit Kit 5 – Earth’s eLISA

Level: intermediate

If you wanna catch a big shark, you’re gonna need a bigger boat. (1970s winter blockbuster reference, anyone?) It’s no different in gravitational wave physics. Gravitational wave detectors that we have on Earth are big, a few thousand metres long, but the next set of detectors? They’ll be truly out of this world!

The European Space Agency (ESA) has a plan to put a gravitational wave detector in space. eLISA (the European Laser Interferometer Space Antenna – yes, it’s a mouthful) is set to launch at some point in the 2030s.

The idea is the same as in Knit Kit 4, racing beams of light along lines the same length, to check if a passing wave stretches or shrinks it in one direction. Except in the case of eLISA, there are no tubes. The three probes aim lasers at each other from millions of kilometres apart.

With a detector of this size, scientists hope to be able to detect some of the biggest events in space – galaxies colliding into each other!

Download the knit kit (PDF, 233KB).

Read more about eLISA.

Knit Kit 6 – Golden Eye

Level: beginner

You might think that all telescopes are the same as the sort you’re used to seeing – two glass lenses and a long thin tube, all on top of a tripod. Those are an important type of telescope, but there are lots of kinds.

Often, you can see telescopes that look like satellite dishes. These are a type of telescope called Newtonian reflectors, and the James Webb Space Telescope is one of them.

This telescope design has a big mirror that reflects light from the object studied onto a light sensor. It works a bit like a bucket collecting rainwater, where the width of the bucket represents the size of the mirror.

A small bucket with a small opening won’t catch a lot of rainwater – a rain drop has to fall in just the right place for it to fall into the bucket. But a huge bucket with a massive width is going to collect every raindrop that falls into it.

In the same way, a bigger mirror collects more light than a small one. The James Webb Space Telescope’s mirror is golden, because that is even better at collecting the kind of light that the sensor is designed for.

Download the knit kit (PDF, 269KB).

Find out more about the James Webb Space Telescope.

Knit Kit 7 – Iron Rain

Level: intermediate

Stars are like people: they come in all shapes and sizes, each one is unique, and each one of them is interesting. Some stars are bigger, others are smaller. Some are hot, others cold, some are old, others are young.

The star in this knit kit is a very small (relatively) cold star, which fits into a group called brown dwarfs. They aren’t big and heavy enough to burn fuel like other stars, so they aren’t as hot. They’re brown, because instead of glowing white hot like our sun, they glow red when they’re young, and slowly dim and change colour as they get older.

When we say that brown dwarfs are “cold”, even the coldest brown dwarfs are hot enough to burn your dinner. Hot brown dwarfs are about 2,000ºC (compared to our sun, which can be tens of millions of degrees), and the coldest brown dwarfs can be as cold as 500ºC. Even though they’re cold, they still can have a lot going on.

Brown dwarfs can have a companion star, orbiting in a two-star system, and researchers have even spotted a planet around a brown dwarf that might be able to support human life.

Download the knit kit (PDF, 225KB).

Find out more about brown dwarfs.

Knit Kit 8 – A Star Scale Sneeze

Level: intermediate

We’ve all seen the sun. That bright thing that hides behind the clouds all summer. Even though it’s the brightest thing in the sky, it isn’t a very bright star – it’s actually a little dimmer than most.

It only looks so bright because it’s so near to us.

In fact, the next nearest star is 300,000 times further away from us than the sun. Even though our sun isn’t exceptional, it’s still unique and interesting. By a long way, it is the most studied star exactly because it’s so ordinary (and it’s far closer than any other star, which helps!).

If we can better understand how our sun works, we can use that knowledge to make a guess at how other stars work – how they’re born, how they burn fuel, what goes on in their atmospheres and how they shape the universe around them.

Something that has had astronomers thinking for a long time are “coronal mass ejections” – that’s where the sun throws off a whole load of matter into its upper atmosphere, making plumes of star-stuff tens of times bigger than the Earth!

Download the knit kit (PDF, 225KB)

Want to find out more about coronal mass ejections? Check this out.

Knit Kit 9 – Pluto’s Heart

Level: beginner

Have you ever heard the saying “if it looks like a duck, swims like a duck, and quacks like a duck, then it probably is a duck”?

It’s called the duck test, and it’s about looking at how something acts and what it looks like in order to work out what it is. Pluto passes the duck test for so-called dwarf planets with flying colours.

Dwarf planets are a kind of object in our solar system that:

1. orbit the sun.

2. hold their (round) shape.

3. share their orbital path with other objects.

4. aren’t the moon of something else.

The list is just like the list which defines a planet, except for planets, the third point says instead: “A planet is the only thing in its orbital path (except for its moons).” Lots of us (especially the older ones) were taught that Pluto was a planet, but in 2005, astronomers discovered a dwarf planet that shared Pluto’s orbit, and was bigger than Pluto, called Eris.

Eris was the first object to be called a dwarf planet, but it was heavier than Pluto, so in 2006, Pluto itself was reassigned as a dwarf planet.

Download the knit kit (PDF, 198KB)

Check out this Pluto fact sheet.

And find out more about the dwarf planets.

Knit Kit 10 – A Pale Blue Dot

Level: beginner

I can’t say any more than Carl Sagan does.

Find out more about Sagan, who wrote and read the passage in the video above.

Download the knit kit (PDF, 99.5KB)

A quilted pattern depicting planets and space

A knitted blanked. Image credit: Jill Martin

How to knit

There are sure to be some seasoned crafters out there, but some of you will be knitting for the first time. To help you along, we’ve put together some links to get you started.

For the knit kits, we used a type of wool called double knit (DK), which tells you how thick the thread is, and 4mm needles – that’s how thick the needles are, and they make the stitches a certain size.

We also say in each knit kit what colours and weight of yarn we recommend, but feel free to knit with what you have. Swap the colours as you like, and use the wool and needles you have available.

All of the knit kits are made the same way, which is using the stocking (or stockinette) stitch. That’s just a fancy way of saying knit one row, purl the next, knit, then purl and so on. All of our knit kits are 40 stitches by 40 rows.

Once you’ve finished the pattern, cast off from the needles and wash and block your square (wet it, squeeze out the excess water, then stretch it and pin it in shape to a cork board or something similar). It’ll hold its shape much better after it’s been washed and blocked.


Read more

Dr Kate Macdonald came up with the idea of Knit the Universe as a way to explore the amazing images coming from the LIGO project.

And she was inspired to act on hearing the mind-boggling answer to a question put to Professor Martin Hendry of the University of Glasgow: how often do black holes collide and make gravitational waves? To which he replied (to paraphrase wildly) – taking into account ifs, buts, ands and maybes, about once every 10-15 minutes, as the universe really is that big.

Putting together amazing images of the stars as knitted squares gives the notion of the fabric of spacetime, a tangible expression, if you like, a map of the cosmos, or a song-line through the universe, to be wondered at, to be marvelled at, to inspire.

Dr Brynley Pearlstone is a science communicator with a background in astrophysics, having earned his PhD in gravitational wave astrophysics at Glasgow university’s prestigious Institute for Gravitational Research. His flagship project, SciCurious, launched in 2019 following a grant from IOP Scotland (IOPS).

Back in the summer of 2020, Kate, an ordinary member of IOPS, was looking for someone to work with on her knitting project. She was put in touch with Bryn by another ordinary member, Becky Douglas. 

Becky and Bryn studied for their PhDs in the same research group at Glasgow. Bryn of course has previously engaged with IOPS, securing the grant. Now Kate and Bryn work together producing knit kits and making the fabric of space time!


Thanks to

Our thanks to Knit the Universe’s science collaborators: Dr Claire Davies, Professor Stefan Kraus, Dr Alison Young, Dr Brynley Pearlstone, Dr Daniel Williams, Laurence Datrier, Professor Harald Pfeiffer, Professor Martin Hendry, Dr Olivia Jones, Dr Peter Levens and Dr Beth Biller.

We’re grateful to our expert team of test knitters: Gordon Shand, Joe Hennell, Dr Kate Macdonald, Karen Vernon-Parry and Dr Brynley Pearlstone. And to the team at IOP Scotland: Mikey Jarrell, Dr Kate Macdonald, Dr Rebecca Douglas, Alison McLure and John Maher.

And also to the core team behind Knit the Universe – Dr Kate Macdonald, Dr Brynley Pearlstone and Mikey Jarrell.