Quoted from The Big Bang Theory:

Penny: Yeah, I do like the one where Lois Lane falls from the helicopter and Superman swooshes down and catches her, which one was that?

Leonard, Sheldon and Howard together: One. (Raj raises one finger).

Sheldon: You realise that scene was rife with scientific inaccuracy.

Penny: Yes, I know, men can’t fly.

Sheldon: Oh no, let’s assume that they can. Lois Lane is falling, accelerating at an initial rate of 32 feet per second per second. Superman swoops down to save her by reaching out two arms of steel. Miss Lane, who is now travelling at approximately 120 miles per hour, hits them, and is immediately sliced into three equal pieces.

Leonard: Unless, Superman matches her speed and decelerates.

Sheldon: In what space, sir, in what space? She’s two feet above the ground. Frankly, if he really loved her, he’d let her hit the pavement. It would be a more merciful death.

Is Sheldon's argument correct?

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    Opinion questions are off topic here. Nov 6, 2013 at 14:36
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    Edited for typos, formatting, and removal of opinion-y bits. I think this is actually just about valid - it's a question about Superman: The Movie, it just happens to have been asked via a sitcom quote. Nov 6, 2013 at 14:45
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    @PaulD.Waite It's asking about real world science, though, which is off-topic. Nov 6, 2013 at 15:18
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    It is valid and it's not a duplicate of the above mentioned queries..
    – Anz Joy
    Nov 6, 2013 at 15:19
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    @AnthonyGrist There are a number of examples of questions asking about "real world science" that aren't off-topic, such as this one. Do you have a source for saying they should be off-topic, or is that just personal opinion? Note the close reason explicitly states "Questions seeking scientific solutions or explanations are off-topic unless they relate directly to a cited work of fiction.". This question relates directly to the movie Superman, as cited in the question.
    – Beofett
    Nov 6, 2013 at 16:50

4 Answers 4


Sheldon's wrong and Leonard is right (Superman matches her speed).

Lois was not two feet above the ground. Superman catches her about half way (approximately) down the building and he slows to a stop then proceeds. So he was matching her speed and slowing so she didn't get hurt.

He does the same thing when the helicopter falls: he catches it and slows to a stop and then places her and the helicopter on the roof.

For additional info see this question on how Superman fails to cause injury.

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    Uhm, your video show him catching her while he is traveling upwards. So if anything, he makes things even worse...
    – Jakob
    Nov 6, 2013 at 15:41
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    @Jakob: nope. If you watch the moment he actually catches her closely, you'll see that she keeps moving down relative to the skyscraper for a second or so after he makes contact with her. Nov 6, 2013 at 15:48
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    Sheldon's problem is his base assumption that Superman's flight is based on jumping really hard off the ground: "It is an extension of his ability to leap tall buildings" - which hasn't been true for quite some time - certainly not post-crisis, and not to earth-one superman for quite a while before that.
    – Random832
    Nov 6, 2013 at 16:04
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    Hmmm perchance you are right...
    – Jakob
    Nov 6, 2013 at 16:06
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    @Michael: that, plus he's either dumb or a troll for not bringing the (broken) copter down to the street for easy transport to the repair shop. Instead he places it atop a skyscraper. Thanks for nothing!
    – RegDwight
    Nov 7, 2013 at 13:00

Most likely, yes.

For someone to slow without injury from a fall of that height would require more space than was available to Superman/Lois between where he caught her and the ground.

It would have been like when Spider-man caught Gwen Stacey when she was thrown off of the bridge - the fall doesn't kill you, it's the sudden stop. It doesn't matter if that stop is derived from Superman's arms, Spidey's webs, or a facefull of concrete or river - stopping that fast will likely be fatal.

That said, we don't see Superman kill her. She's fine. She survived the fall without injury.

The only explanation that makes any sort of sense is that Superman has a malleable field of force around him into which he dumped the kinetic energy Lois was carrying. This field of energy isn't a new theory - it was the official rationale behind most of Superman's physical powers for a while in the 90s, and it was used to explain how he could lift things like battleships (which would be crushed under the own weight if supported by a human-sized object outside of water).

Flash has a similar energy field around him, which is what lets him avoid friction and not cause sonic booms everywhere he goes. It's a common thing in DC comics, and the only explanation which permits a living Lois at the end of that scene in Superman 1.

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    djm's answer asserts that he caught her halfway down the building, not two feet above the ground. If it's literally halfway, than her deceleration needs not be at any greater rate than the original acceleration, and she will only experience 2 G's of force.
    – Random832
    Nov 6, 2013 at 16:10
  • Maybe I'm missing something in the math, but if the total fall is distance d, she accelerates downwards at 1G for a distance of d/2, then is caught and reverses her previous acceleration over the same distance d/2, shouldn't she also have 1G (in the opposite direction) when she decelerates? I mean, there's probably some wiggle room for him to have not caught her at exactly d/2, and to maybe stop her a few feet above ground and then reaccelerate back towards the ground, but even 2G seems like a generous estimate to me?
    – PeterL
    Nov 6, 2013 at 17:04
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    @PeterL You have to add in the acceleration of gravity, which never ceases. Acceleration of the body is different than acceleration felt by the body. (You feel 1G right now just sitting at your chair, even though you're not actually accelerating anywhere)
    – Izkata
    Nov 6, 2013 at 18:14
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    Likewise, she feels 0 G's (or a negligible amount due to air resistance) while in free fall, not 1.
    – Random832
    Nov 6, 2013 at 18:36
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    Show's what I get for assuming Sheldon was being truthful. In any case, this explanation will suffice quite well for all the OTHER times Superman has saved someone with a tenth of a second between falling and street pizza.
    – Jeff
    Nov 6, 2013 at 19:27

This idea is so common it has a page on tvtropes. But in that same film is a scene of the two of them flying together that clearly establishes the rule (for some reason I can't find a YouTube clip that shows it). He's not carrying her, they're flying together; as long as they're touching, even just their fingertips, she's as immune to gravity as he is, and whatever acceleration he imposes doesn't strain her at all.

That's how he can catch her without so much as a bruise, and catch a helicopter in a way that "should" tear it to pieces. Presumably he could have done the same thing two feet above the pavement, but that would have looked so weird it would have jarred the viewers right out of the scene.

  • See this link:scifi.stackexchange.com/questions/43754/… Superman has gravity fields around him that protect whatever he's lifting/carrying
    – djm
    Dec 3, 2013 at 2:55
  • And while I love Superman the Movie; that flying scene and whole "Can you read my mind" montage should have been, IMHO, heavily edited or left on the cutting room floor entirely.
    – djm
    Dec 3, 2013 at 2:58
  • @djm: The "Can You Read My Mind" poem was painful, and I think the shots that explicitly identify Metropolis with New York City were a mistake. But I have to admit that apart from those flaws (and the technical FX limitations of the time) I think it's one of the most beautiful love scenes I've ever seen.
    – Beta
    Dec 3, 2013 at 3:17
  • IIRC, he holds up the helicopter by one strut of one landing skid, leading me to assume that he has some telekinetic power to spread force evenly. This would also explain how he can take her flying and just barely touch her fingertips. In a similar vein, the John Byrne reboot of the character introduced an "invulnerability field" that protected Superman's costume and possibly people he carried in his arms, but left the tip of his cape vulnerable to bullets and such. scifi.stackexchange.com/questions/20151/…
    – steveha
    Feb 4, 2014 at 21:13

The way that Superman flies is that he decreases his mass by using an organ people from Krypton have developed to conteract the enormous force of Krypton gravity so for Superman to fly up he has to lower his mass to less than air making the force of Superman hitting Lois is much less than Lois hitting the pavement, it is more like Lois landing on a giant soft pillow, therefore he decelerates her enough for her to survive.


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