we-are-star-stuff:

As much as we’d all love to believe that a random mishap involving an irradiated arachnid could turn us into a crusader for truth, justice and whatever way we please, science tells us that the world is a lot more temperate when it comes to doling out super powers. So, how does the science of superheroes stack up when it’s put under the microscope?

Superman

Consider Superman simply hovering above the city. According to Newton’s Second Law, there must be some upward force to balance the downward force of his weight. Expressed mathematically: F – mg = ma = 0. But what could cause that upward force?

One possibility is that he is able to emit high-velocity streams of air through the pores of his skin. As he forces the air out of his body, according to Newton’s Third Law, the expelled air must push back. And since Superman can survive in space, his lungs clearly aren’t needed for respiration – maybe they’re auxiliary air tanks.

It’s said Superman’s great strength comes from the gravity difference between Krypton and Earth. That strength has been estimated as enabling him to lift between 100 tonnes and 800,000 tonnes. Let’s take a conservative estimate of 1,000 tonnes and run the numbers. Your average buff mid-20s male can bench-press about 100 kilograms. That means Superman can lift 10,000 times more than our Average Joe.

Assuming that 1,000 tonnes on Earth is equivalent to 100 kg on Krypton, the gravity on Krypton must be 10,000 times more intense. That’s one dense planet! So dense, in fact, that its surface gravity (assuming a similar diameter to Earth) would be 370 times even that of the Sun. A box of Krypton Corn Flakes would crush poor old Average Joe.

Then we have kryptonite, the mythical element that was created at the explosion of Krypton, whose green variety can be lethal to our favourite man of steel. In the Superman tales, kryptonite is described as an element, although the suffix ‘-ite’ is often reserved for compounds of two or more elements. As such, it has been suggested that kryptonite could be a compound of krypton and something else. But krypton is a noble gas, is very unreactive and doesn’t form compounds easily.

Storm

A classic superhero conundrum: Where do these people get the energy to perform their superhuman feats? In the X-men movies, the “mutant” Storm is able to generate bolts of lightning at will. The energy released in a normal lightning bolt is about 500 million joules, which is equivalent to 120,000 food calories. To produce even a single lightning bolt, Storm would have to eat at least 60 times the recommended daily amount for an adult female. But we don’t see her constantly cramming down food in the movie, do we?

If her stomach has mutated into some type of nuclear-fusion reactor, however – or better yet, a matter/anti-matter reactor – she could do it. Applying relativity (E = mc2), a single gram of mass converted completely into energy would yield 90 trillion joules. That’s 18 million lightning bolts!

The Hulk

One of the best ways to become a superhero is to be bombarded with tremendous doses of either cosmic rays or high-energy electromagnetic radiation. Although the effect of high doses of these types of radiation on humans (in the real world) are well-documented (the typical result is severe and debilitating cell destruction, followed by death) in the superhero world, this normally lethal experience results in a sequence of fortuitous “mutations”.

These physiological changes always create abilities so astonishing that it might convince the most cautious of us to risk spending a couple days in the reaction chamber of a high-energy particle accelerator. Banner was accidentally exposed to gamma rays when testing a gamma bomb, triggering an unusual transformation in the scientist.

While it’s common for individual organisms to grow to great size during their lifetimes, trebling in size and cubing in body mass in a matter of seconds would be a tricky manoeuvre. Even if the cells were built for such replication, the energy required would be immense – matter doesn’t just pop out of nowhere, after all. 

The Human Torch

Johnny Storm, “the Torch” from the Fantastic Four comics and movies, combines each of the attributes that we touched upon with our first three superheroes. Having been exposed to “lethal” doses of cosmic radiation, Johnny (of course) develops formidable superpowers, just like the Hulk. He can fly, so as with Superman, we hypothesize that he forcibly expels gas at high velocities in the appropriate directions. And he also has a Storm-like propensity for churning up energy: Applying a little thermodynamics, we can calculate that he would have to generate around 940 million joules to “flame on” to a temperature of 5,000˚C.

That’s pretty amazing considering that amino acids, the building blocks of life as we know it, break down at temperatures not much over 100˚F. How Johnny’s DNA is able to withstand such high heat is a mystery – not to mention that all the water in his body should long since be vaporized by the time he ignites.

Magneto

Magneto is a super-villain with the ability to create extremely powerful magnetic fields at will. Since magnetic fields are produced by electric currents, we can roughly approximate the current that might be coursing through Magneto when he’s up to one of his evil deeds. For simplicity, let’s model his interior electrical circuitry as a large solenoid (coil). The magnetic energy stored in a solenoid is given by:

U = ½(μ0n2AL)I2

Where U is the energy, μ0 is a constant equal to 4π x 10-7 N/A2 , n is the number of coils in the solenoid, A is the cross-sectional area of the solenoid, L is the length of the solenoid, and I is the current generating the magnetic field. Phew. Let’s assume that Magneto’s internal solenoid has 1,000 turns, has a cross-sectional area of 0.01m2 and is approximately 2 meters long.

Now let’s say that he uses that energy to lift a 1,000kg automobile 10 meters off the ground, increasing its potential energy by an amount U = mgh = (1,000 kg)(10m/s2)(10m) = 100,000 J.

Plugging this value into the first equation and solving for I, we get that in order to store this much energy in his magnetic field, Magneto must generate a current of around 2,900 amps. That might not be so good for his heart – assuming he has one.

The Sandman

The Sandman, that reluctant super-villain from Spiderman 3, represents the metaphysical end point of all superpowers. He exists so far into the realm of fantasy that we just have to enjoy the astonishing computer graphics. Created in another generic high-energy-particle experiment, he is able to defy all laws of physical and biological probability. Somehow the matter in his body is all converted into sand (SiO2) in the ill-fated experiment. Apparently he has no internal organs (he can disintegrate and reconstitute himself at will), he can move without muscles, and he can even fly through the air as a cloud of dust. How does he produce energy? Can he metabolize food? How does he exert forces? Only the CGI magicians at Sony know for sure.

Batman

We all know that Batman has no superpowers. He’s just a highly motivated and highly skilled crime fighter with a lot of tech support. Or is he?

In fact, to survive intact some of the impacts he undergoes, Batman actually might require super strength. A classic movie-physics blunder is the sudden stop. Now, we see this in a variety of forms in the original Batman. At one point, he plunges from the top of a building, along with Kim Basinger, to what appears to be certain death. Their fall, however, is arrested by a (decidedly inflexible) rope before hitting the ground. The thing is, it doesn’t matter if you hit the ground or not. If the time it takes for the rope to bring you to a stop is the same as if you hit the ground, then the force exerted on you will be the same in each case.

Iron Man

Like Batman, Ironman has no superpowers, but he does have that amazing iron suit. In the movies we see him flying around in his nifty suit next to some military jets. There are little rocket flames coming out of the bottoms of his shoes, apparently providing the necessary thrust.

Questions: what is he using for fuel? Based on what we see, it looks like rocket fuel. But where are his fuel tanks? And what volume of rocket fuel would he need to maintain the necessary thrust for at least several minutes? Would it be difficult for him to stay aloft in a stable trajectory? What does he wear underneath his suit?

Spider-Man

Spider-Man has always had scientific overtones, from Peter Parker’s preferred subjects at school, to the premise of a man-animal fusion instead of magical or alien powers. Having said that, it’s worth noting that there have been no recorded cases of radioactive spider bites causing anything other than irritation and mild inflammation in humans.

At a stretch, it’s just about possible to imagine the radiation that bombarded the spider changed its DNA in such a way that when its venom was injected into poor Peter, it managed to penetrate his cells and fuse with his own DNA. This could have started a series of mutations in Peter, giving him some of the characteristics of a spider.

Among Spider-Man’s slender but impressive range of powers is his super grip, which is ideal for clinging to walls, ceilings and beer cans in high-wind situations. Some spiders, like some insects, have specialised hairs at the base of their feet that can find their way around the microscopic bumps and crevices in most surfaces.

Creepy crawlies are also assisted by the fact they are very small compared to people, which means the ratio of body mass to surface area in contact with the wall is favourable. Things would be a little tougher for Spider-Man though, because when you double an organism’s size, you square its mass. This means Spidey’s extremities must have incredible adhesive power (that is, very hairy palms).

Spider-Man also posesses the strength and agility of a spider, proportionally magnified into human scale. And although spiders lack the relative strength of ants or other insects, any organism that is as small as a spider will appear to be super strong at its scale, when compared to a human being. Assuming Spidey’s strength has been proportionally boosted, it’s plausible he would be able to lift several tonnes.

Regarding Spider-Man’s last remaining, and possibly most remarkable power, his spider sense, things become somewhat hazier still. Spiders do have specialised hairs, called setae, which are connected directly to the spider’s nervous system and provide the arachnid with a detailed picture of anything it touches. However, when it comes down to being able to detect the cool aim and deadly intention of an evil-doing sniper on the top of an office building several hundred metres away, well, hairs ain’t going to help Spidey too much there.

Extra: what killed Gwen Stacy?

In “The Amazing Spider-Man” No. 121, the Green Goblin knocks Spider-Man’s girlfriend Gwen Stacy off of a bridge. Spider-Man catches her mid-fall with his web, but when he pulls her to safety she is dead. Her death was the result of the conservation of momentum. When she is thrown from the bridge, her velocity increases due to gravity. By the time Spider-Man catches her 300 feet down she is traveling at 95 miles per hour. That velocity goes from 95 miles per hour to 0 in the short time the webbing catches Stacy, creating the same results as a high-speed car crash – too much force is needed to bring the 110-pound girl to a stop. If Spider-Man had slowed her deceleration gradually, the way a car’s airbag slows you down over several milliseconds during a crash, she might have survived.

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@Binals a good read

this is so clever i love it

venusmilk:

Fairy tales of Hans Andersen (1908)
Illustrations by Helen Stratton

“She held his head above the water, and then let the waves carry them whither they pleased”

wardkimball:

Things That The Walt Disney Company Won’t Allow To Be Published In A Ward Kimball Biography (Part 1 of 5,000): This self-portrait that Ward drew for Bob Foster.