The 62nd Eurovision Song Content (ESC) is taking place this May in Kiev. All 43 participating countries have submitted their songs and the corresponding music videos/live performances are available for viewing/listening on the ESC’s official YouTube channel. Feel free to watch them at your leisure if you haven’t. Though if you’re reading this, you’ve likely seen some of them by now. (You could also be completely ignorant about the ESC and are reading this without having a clue what I’m talking about.)

The competition aside, I was listening to one of the songs – Cyprus’s Gravity – and my science!nerd brain had a tangential thought on the opening stanzas: “No matter where you’re going / Now matter where you’ll be / Wherever the wind is blowing / Let me be your gravity“. That thought was that any object with mass exerts a gravitational field – though for non-astronomical bodies (like humans) it’s super duper weak. And a gravitational field exists through all of space, though getting weaker as the distance between the two bodies increases. So, the singer Hovig is already a source of gravity for this anonymous other person (wind blowing or not).

This thought, of course, led to one more general: Can you turn Eurovision lyrics into mini science lessons?

Let me see what I can come up with.

The Songs…Or at least 9 of them…

Click below to jump to the county of your choice, or just start scrolling

• Armenia
• Australia
• Austria
• Azerbaijan
• Cyprus
• Hungary
• Israel
• Montenegro
• Poland

• Fly With Me (Armenia – Artsvik)
  • Lyrics: “Wanna tell a story / About a girl with history
    Take it from my heart it’s gonna be your beat“
  • Science tangent: Ignoring what ‘it’ is in the lyrics, can one human’s heartbeats affect those of another?
    • A 2013 study of 32 heterosexual couples (mostly white & between 20-40 years old) found that, when sat a few feet away from each other and told to “mimic each other” (but not speak), their heart rates and breathing synchronized – usually the women’s patterns changing to match the man’s. Non-coupled pairs did not synchronize under the same conditions.
    • A 2011 study collected heart rates for 12 male fire-walkers and 26 onlookers – both relatives/friends of the walker (9) and visitors unrelated to anyone in the village (17). The heart rates of fire-walkers and relations spiked at the same time (a sensation called “synchronized arousal”); spectators not connected to the walker did not spike at all. (The heart rates themselves didn’t match, but they increased/decreased at roughly the same time). Basically, your own stress symptoms (well, at least your increased heart rate) can be transmitted to those watching you, but ‘only’ if they know you.

• Don’t Come Easy (Australia – Isaiah)
  • Lyrics: “And if you think I’ve got a heart of stone you couldn’t be more wrong”
  • Science tangent: Can one actually develop a heart of stone?
    • Fibrodysplasia Ossificans Progressiva (FOP for short) is a very rare disease caused by a genetic mutation that affects the body’s connective tissues (including muscle, but also tendon and ligament). When damaged, the body doesn’t repair them correctly – instead, they ossify. That is, they turn into bone (So, not stone exactly, but mineralized). Joints eventually fuse together, and the condition will become so severe that the victim is locked inside their body, struggling to breathe; individuals with FOP usually die around the age of 40 or so, assuming they don’t suffer horrible trauma that accelerates the ossification rate drastically.
      There’s no known cure.

    • 

      However, the ossification doesn’t affect everything; cardiac muscles are one of the exceptions. (Others include the diaphragm, tongue, and muscles that move the eyes.) So no heart of ‘stone’.

• Running On Air (Austria – Nathan Trent)
  • Science tangent: How might one run on air?
    • Aerogel is a synthetic material that – as its name might imply – is made from a gel and air. It’s basically the most extreme version of styrofoam you can think of, and is nicknamed “Frozen Smoke”. ‘Cause that’s what it looks like.

      

    • Aerogel is about 98% air, an amazing thermal insulator, and (structurally) amazingly strong. Here’s 2 grams of the stuff supporting a brick over 1000x the weight:

      

    • It might not be able to support the downward force of a running foot, but if you wore shoes large enough to distribute your weight over a larger surface area, you could totally run on 98% air.

• Skeletons (Azerbaijan – Dihaj)
  • Lyrics: “The world is spinning faster by the minute”
  • Science tangent: Is the world spinning faster than it was last minute?
    • Short answer: In general, no. In fact, it’s the opposite.
    • Less short answer: The Earth’s average rate of rotation (and therefore the length of each day) is slowing down because of the Moon’s gravity. Why? Currently, it takes the Earth less time to complete one rotation than it does the Moon to complete one revolution around the Earth. So, like an uncooperative child grabbing onto their faster-walking parent, the Moon’s gravity is constantly tugging on the Earth – the entire planet, not just the water (causing tides) – slowly slowing down its spin. The length of an Earth day is slowing by about 0.002 seconds every century.
    • However, on a much smaller scale, the speed of the Earth’s rotation can both speed up and slow down due to factors other than the Moon’s tidal pull. The 2004 Indian Ocean earthquake sped up rotation by about 0.003 seconds. Anything that redistributes mass can change how fast the planet spins – the melting of large ice structures, the drifting of continents, a mysterious flowing subsurface layer like the mantle…even something as mundane as the water cycle (water evaporating, moving in large masses better known as clouds by wind to new locations, and raining down…).

• Gravity (Cyprus – Hovig)
  I already stated some thoughts on this above, but here’s a little more detail
  • Lyrics: “No matter where you’re going / No matter where you’ll be / Wherever the wind is blowing / Let me be your gravity”
  • Science Tangent: Can a human be a source of gravity for another human being?
    • To calculate the gravitational force between any two massive bodies (“massive” meaning they have mass – not that they’re large. A single atom is massive…), you’d use Newton’s Law of Universal Gravitation:
      • F = G×M₁×M₂ ÷ r²
        G: 6.67×10^-11 m³/(kg·s²), known as the “Gravitational constant”
        M₁: mass of object 1 (in kg)
        M₂: mass of object 2 (in kg)
        r: distance between object 1 and 2’s centers of mass (in m)
    • Because G is so small (0.0000000000667), it takes a lot of mass before gravity is noticeable. For 2 human beings (70 kg each) standing 1 meter apart, the force would be 0.000000327 Newtons. The Earth exerts a force of 686 Newtons on each human – about 2.1 billion times stronger a pull.
    • If the Earth weren’t in the picture – that is, if we plopped Hovig and his partner in the void of interstellar space (say, 2 lightyears from the Sun) – the gravitational force between them would be stronger than the gravity from any other astronomical body. Assuming they were plopped there with no starting velocities, they’d both very slowly start falling toward each other.
    • That’s an important part I sort of glossed over, earlier – gravity is never one-way. You exert the exact same amount of gravitational force on the entire Earth that the Earth does on you, but in the opposite direction. Hovig’s partner is equally his gravity.

• Origo (Hungary – Jaci Pápai)
  • Lyrics: “You knew my eyes were brown / And they will never change” (Originally “Tudtad barna a szemem / Sosem változik bennem”)
  • Science tangent: Can you change your eye colour (ignoring coloured contacts)?
    • Human eye colour is determined by a couple of factors.
      The first is the colour of the iris itself – determined by the amount of a pigment (mostly melanin, equivalent but not identical to the melanin that affects skin color). This pigmentation ranges from light brown to black (not blue/green/etc.), except in those with albinism where there’s no pigmentation at all. It’s regulated by genetics.
      The second is how light is scattered within a layer of the iris called the stroma.
      • Blue: dark under layer + little pigment in stroma – redder light is absorbed by the former and bluer light gets scattered in the latter
      • Grey: dark under layer + little pigment in stroma. It’s unknown exactly why they’re not blue, but it might be similar to how having more water in the atmosphere makes the sky look grey instead of its usual blue (though here it’s not water, but having larger versions of the protein collagen in the stroma). You can read more here.
      • Brown: lots of melanin in both
      • Green: low to moderate pigmentation in the stroma (melanin + the yellowish lipochrome), so scattering still occurs
    • Many babies with European ancestry are born with blue eyes, but cells in the eyes start producing melanin after birth and the color slowly darkens. Changes in hormones – for example as a result of puberty or pregnancy – can also theoretically alter one’s eye colour, as can physical injury or disease. This study (done on twins) found that 18.2% of hazel/light brown-eyed and 16.2% of brown-eyed white subjects had lighter eyes as an adult than when they were 6 years old. Also, 11% of their mothers had their irises change colour (either direction).
    • Cosmetic surgeries can artificially change the colour of your eyes, like shooting a laser into the iris to get it to slough off some of its melanin-laden tissue so a brown eye appears bluer (This is not currently available, still undergoing study for both efficacy and safety). Or you could get a coloured disk (an artificial iris) inserted into your eyeball (I’m cringing just typing this…Also, what about the whole hole over the pupil not being able to change size?)

• I Feel Alive (Israel – IMRI)
  • Lyrics: “Walking through the stars”
  • Science tangent: How long would it take you, traveling at a velocity equivalent to a walking pace (5 kph), to travel from one star to another?
    • Obviously this depends on the distance between stars. If IMRI wants to go from our solar system to the next star over – Proxima Centauri – it would take about 8 trillion hours, or about 9 billion years. However, Proxima Centauri (a red dwarf only about 13% the size of our Sun) is part of a trinary star system along with Alpha Centauri A (a star just a bit larger than our own Sun) and Alpha Centauri B (a star a bit smaller than the Sun). So they’re all much closer together to each other than they are to other stars in the neighborhood. To the naked eye, stars A and B appear as a single star in the night sky (Proxima Centauri isn’t visible); they orbit one another, so the distance between them varies. At their closest – roughly the same distance as Saturn is from the Sun – it would take IMRI about 38,000 years to ‘walk’ from α Cen A to α Cen B.
    • The binary system whose ‘stars’ are the closest together (at least currently known) is the catalogue-ly named RX J0806.3+1527. They’re super dense stellar remnants (i.e. white dwarfs) only about 80,000 km apart – that’s a fifth of the distance between the Earth and the Moon! (They orbit each other every 5 minutes.) If you’re willing to extend your definition of “stars” to include the cores of dead ones, this is the best chance IMRI’s got. It’d take him less than 2 years to walk from one to the other.
    • Setting lone pairs of stars aside, very large clusters of stars also exist. They come in two flavours: globular clusters (spherical in shape, found mostly outside of the galactic disk, and in general the oldest objects in the galaxy) and open clusters (in which the stars are less bound to each other and generally less dense (and with fewer stars) save an optional small core of stars). This is one of the densest clusters we know of, globular Messier 75, packing the light of 180,000 Suns into a sphere of radius 67 lightyears:

      

      Globular cluster cores can pack as many as 1000 stars per cubic parsec of space (1 pc = 3.26 ly), about 1000 times more concentrated than our own stellar neighborhood.

    • At the very center of the Milky Way, there are as many as 10 million stars packed into a single cubic parsec. At that density, if we made a sphere around the Sun with the Alpha Centauri system sitting on the edge, there’d be 96 million stars inside it. Each star would only be about 20 billion km from the next…which would still take over 450,000 years to walk between each.

• Space (Montenegro – Slavko Kalezić)
  • Lyrics (there’s a whole bunch of references to space): “Let’s soar through the Milky Way”
    • Science tangent: How far through the Milky Way could you get in a human lifetime?
      • Assuming you are traveling through regular space (i.e. not using wormholes – which are technically still theoretical – or a fancy futuristic technology that allows you to warp space or travel outside of our established dimensions of space), the fastest anything can go is ~300 billion meters per second (about 1 billion kph). This is the fundamental speed limit of the universe, and the speed that light travels in a vacuum. We define the distance lightyear as the length light can travel in a vacuum over one Earth year. The Milky Way is very roughly 100,000 lightyears in diameter.
      • The average lifespan for a male from Montenegro is 74.1. Slavko was born in 1985, leaving him 42.63 years of travel time, assuming he starts right now. While no object with mass can travel at the speed of light (It would take an infinite amount of energy to accelerate that object to that speed), we can accelerate particles to 99.999999% the speed of light in the Large Hadron Collider. Obviously a human being isn’t the same as a single subatomic particle, but let’s ignore that for the purposes of this thought exercise and pretend Slavko and partner can go this fast, too.
      • Traveling that fast invokes Special Relativity – specifically, time dilation. Slavko and his partner’s body clocks would slow down, meaning that they’ll actually be able to travel further than 42.63 lightyears before dying. In fact, traveling at 99.999999% the speed of light would slow their perception of the passage of time by a factor of over 9000 7000. They’d be able to traverse over 300,000 lightyears in the remainder of their lifetimes. So yeah, they totally could ‘soar’ through a section of the Milky Way – but once they returned to Earth everyone else they knew and everyone they knew would have been dead for hundreds of thousands of years.
      • The fastest humans ever were the three crewmen of Apollo 10 on return from the Moon, hitting 39,897 kph. At that speed, Slavko and company would only make it 15 billion km in their (approximate) lifetimes, which while far beyond the orbit of Pluto is still inside the Solar System.
  • Bonus Lyrics: “I have my suit on, no need to worry”
    • Yes you do. Accidents happen. Equipment fails and suits tear.
    • Astronaut Luca Parmitano almost drowned inside his suit after water (used for cooling) started leaking into his helmet while performing a spacewalk.
    • There’s also the threat of micrometeorites – flecks of dust traveling at tens of thousands of kph that still have enough energy to chip a helmet, exposing your body to the vacuum of space. (Luckily, this has not happened to anyone…)
    • Don’t forget large radiation doses coming from stars, pulsars, etc.

• Flashlight (Poland – Kasia Moś)
  • Lyrics: “Running faster at the speed of light”
    • Science tangent: Can you ‘run’ at the speed of light?
      • Only massless particles can travel at the speed of light in a vacuum (that 300 billion number I threw at you earlier), but light doesn’t always travel at that speed. Through any other medium, photons slow down, for the same reason that you’d slow down if you had to smash into a bunch of stuff as you ran between two locations. Back in the late 90’s researchers at the Rowland Institute for Science slowed light down to a whopping 17 meters per second (Not exactly running speed, but about 20 million times slower than it had been going) by sending it through a special ‘extreme’ phase of matter known as a “Bose-Einstein Condensate” – lots of atoms packed together at billionths of a degree above absolute zero and almost vacuum pressure which start acting more like a single superatom. A 2009 paper shows that light was slowed to 10 m/s and also “stored” (effectively stopped) inside a BEC for over 1 second.
      • If the person running was Usain Bolt – who holds the record for fastest footspeed – 12.4 m/s – and everything was timed correctly so he hit his maxish speed as the pulse of light were entering the BEC, then yes, ‘you’ can run faster than the speed of light.