# The Earth now has 95% of its former gravity, what happens? **URL:** \ **Category:** Factual Questions\ **Created:** [June 8, 2011, 9:39pm UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786 "2011-06-08T21:39:24Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [June 9, 2011, 12:02am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/21 "2011-06-09T00:02:23Z")
> [@Alka\_Seltzer](#): > > No, you wouldn’t notice this, as you don’t accelerate anywhere when you are standing on the floor. Your feet remain planted on the elevator floor, too. Physically, there is no _local_ difference between an accelerating elevator and standing on the surface of a planet. This was Einstein’s great insight which led to General Relativity. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [June 9, 2011, 12:06am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/22 "2011-06-09T00:06:28Z")
I have a feeling one or two people in this thread may have misread the question as asking what would happen if gravity was reduced **by** 95%… ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [June 9, 2011, 12:10am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/23 "2011-06-09T00:10:46Z")
> [@Mangetout](#): > > I have a feeling one or two people in this thread may have misread the question as asking what would happen if gravity was reduced **by** 95%… I know I didn’t. And I don’t get the impression anybody else here has either. Care to share? Even if the change aint fast, it would have measurable effects in many ways. Whether those were just changes or had drastic consequences is something else. ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [June 9, 2011, 12:16am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/24 "2011-06-09T00:16:07Z")
> [@Alka\_Seltzer](#): > > I wonder what would happen to a loaded structure, such as a suspension bridge? First order WAG. Assume the distance between the lowest part of the cable and the deck is 100 feet. The deck would rise about 5 feet (probably a bit more). So, a suspension bridge deck would become more convex (less flat) that it was before the big G loss of 011. Even a normal bridge is designed to be flat with a given G. Lessen that G and its gonna be less flat/ more convex. ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [June 9, 2011, 12:20am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/25 "2011-06-09T00:20:28Z")
Wouldn’t a 5% drop be enough to effect all the satellites orbiting the earth? Geo-stationary ones would no longer be stationary. So all the devices people use that depend on them would start to malfunction: GPS navigators, satellite transmission of phone calls, TV, etc., cellphone GPS locaters, scientific experiments, etc. I would think that would be noticed pretty quickly. ---
**Author:** ![The\_Hamster\_King](https://avatars.discourse-cdn.com/v4/letter/t/8edcca/32.png) [@The\_Hamster\_King](https://boards.straightdope.com/u/The_Hamster_King)\ **Post date:** [June 9, 2011, 12:45am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/26 "2011-06-09T00:45:03Z")
> [@Alka\_Seltzer](#): > > No, you wouldn’t notice this, as you don’t accelerate anywhere when you are standing on the floor. The effects of gravity and acceleration are indistinguishable. It would feel exactly the same as being in an elevator accelerating down at about half the typical amount. Only it wouldn’t stop. With an elevator you get an initial dropping feeling that subsides as the elevator reaches maximum velocity. If the gravity of the Earth suddenly decreased by 5% you’d instantly feel the same faint dropping feeling, but it wouldn’t go away. (Until you adjusted to it psychologically, of course. But that might take minutes, hours, or even days.) ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [June 9, 2011, 1:04am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/27 "2011-06-09T01:04:24Z")
> [@billfish678](#): > > I know I didn’t. And I don’t get the impression anybody else here has either. Care to share? I’m probably just misreading it then - no matter. ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [June 9, 2011, 1:41am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/28 "2011-06-09T01:41:38Z")
> [@Mangetout](#): > > I’m probably just misreading it then - no matter. Fair enough. Happens to us all once in awhile. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [June 9, 2011, 2:27am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/29 "2011-06-09T02:27:27Z")
I still maintain that everyone would suddenly become very clumsy. Walking is basically a process of falling forward and moving your feet in front to catch yourself. Change the rate at which you fall, and your reflexes for when to move your feet where will be all wrong. This is not like putting on or taking off a heavy backpack; that doesn’t change the rate of falling. Now, it might still take a little while for folks to figure out the cause of the sudden worldwide clumsiness. But once people know to look for _something_, it won’t take them long to notice that pendulum clocks and spring scales are also off, and then you’ve got it. ---
**Author:** ![treis](https://avatars.discourse-cdn.com/v4/letter/t/bc79bd/32.png) [@treis](https://boards.straightdope.com/u/treis)\ **Post date:** [June 9, 2011, 2:35am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/30 "2011-06-09T02:35:34Z")
> [@Chronos](#): > > I still maintain that everyone would suddenly become very clumsy. Walking is basically a process of falling forward and moving your feet in front to catch yourself. Change the rate at which you fall, and your reflexes for when to move your feet where will be all wrong. This is not like putting on or taking off a heavy backpack; that doesn’t change the rate of falling. > > Now, it might still take a little while for folks to figure out the cause of the sudden worldwide clumsiness. But once people know to look for _something_, it won’t take them long to notice that pendulum clocks and spring scales are also off, and then you’ve got it. The astronauts on the moon didn’t have a noticeable problem hopping around. I don’t have a problem walking in water. I can walk reasonably well on a trampoline. Basically, I think you are vastly overstating the problems with walking. ---
**Author:** ![Fear\_Itself](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/fear_itself/32/19637_2.png) [@Fear\_Itself](https://boards.straightdope.com/u/Fear_Itself)\ **Post date:** [June 9, 2011, 2:40am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/31 "2011-06-09T02:40:04Z")
> [@treis](#): > > The astronauts on the moon didn’t have a noticeable problem hopping around. They trained hundreds of hours in simulators to prepare for it. ---
**Author:** ![Heracles](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/heracles/32/487_2.png) [@Heracles](https://boards.straightdope.com/u/Heracles)\ **Post date:** [June 9, 2011, 2:48am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/32 "2011-06-09T02:48:28Z")
Wouldn’t at least some [construction cranes](http://hwashn.en.made-in-china.com/offer/teznsLXKHuWf/Sell-Tower-Crane-QTZ-80-5613-.html) tip over? I mean, aren’t these things balanced so that ( the weight at the end of the boom \* the forward length of the boom ) = ( the counterweight \* the back-length of the boom )? So if you decrease both weights by 5%, the balance isn’t good anymore? On a smaller scale, many desk lamps wouldn’t stand right all of a sudden. ---
**Author:** ![The\_Hamster\_King](https://avatars.discourse-cdn.com/v4/letter/t/8edcca/32.png) [@The\_Hamster\_King](https://boards.straightdope.com/u/The_Hamster_King)\ **Post date:** [June 9, 2011, 2:51am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/33 "2011-06-09T02:51:33Z")
> [@Chronos](#): > > I still maintain that everyone would suddenly become very clumsy. I agree. ---
**Author:** ![Heracles](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/heracles/32/487_2.png) [@Heracles](https://boards.straightdope.com/u/Heracles)\ **Post date:** [June 9, 2011, 2:56am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/34 "2011-06-09T02:56:39Z")
Also: - Some automated assembly lines wouldn’t work because, say, a paint container designed to hold N kg of paint would overflow before it reached the specified weight; - They’d have an unusually high number of injuries at the various Cirque du Soleil shows, from all the aerial acrobatics that just didn’t work like the day before; - Ships would run higher in the water, possibly causing a few collisions with low bridges. ---
**Author:** ![Heracles](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/heracles/32/487_2.png) [@Heracles](https://boards.straightdope.com/u/Heracles)\ **Post date:** [June 9, 2011, 3:01am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/35 "2011-06-09T03:01:34Z")
> [@Heracles](#): > > I mean, aren’t these things balanced so that ( the weight at the end of the boom \* the forward length of the boom ) = ( the counterweight \* the back-length of the boom )? So if you decrease both weights by 5%, the balance isn’t good anymore? > > On a smaller scale, many desk lamps wouldn’t stand right all of a sudden. All right, that was silly. Multiply both sides of the equation by 95% and it’s still balanced. Sorry about that. :smack: ---
**Author:** ![MuleSkinner](https://avatars.discourse-cdn.com/v4/letter/m/779978/32.png) [@MuleSkinner](https://boards.straightdope.com/u/MuleSkinner)\ **Post date:** [June 9, 2011, 3:33am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/36 "2011-06-09T03:33:04Z")
> [@Chronos](#): > > Everyone would notice at the same time, when we all suddenly started tripping over our own feet. Walking is a lot more complicated than most folks realize; we’re just really practiced at it. Wouldn’t the effect be similar to someone that’s 100lbs. taking off 5lbs. of clothing and walking? Or losing 5lbs. of feces and fluids? ---
**Author:** ![MikeS](https://avatars.discourse-cdn.com/v4/letter/m/919ad9/32.png) [@MikeS](https://boards.straightdope.com/u/MikeS)\ **Post date:** [June 9, 2011, 3:48am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/37 "2011-06-09T03:48:47Z")
Civic water systems that relied on a water tower would experience a 5% drop in water pressure. Whether this would be immediately noticeable, I’m not sure. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [June 9, 2011, 7:29am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/38 "2011-06-09T07:29:50Z")
> [@MuleSkinner](#): > > Wouldn’t the effect be similar to someone that’s 100lbs. taking off 5lbs. of clothing and walking? Or losing 5lbs. of feces and fluids? No, because (aside from buoyancy and air resistance) the speed at which objects fall is a function of the gravitational force acting on them, not their weight - **Chronos** makes a good point here, although I wonder whether 5% would be within tolerance for us just to adapt behaviourally, rather than by evolution. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [June 9, 2011, 7:32am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/39 "2011-06-09T07:32:06Z")
> [@MikeS](#): > > Civic water systems that relied on a water tower would experience a 5% drop in water pressure. Whether this would be immediately noticeable, I’m not sure. Some of this would be mitigated by the fact that water would still rise to the same level, because the lower gravity means water is correspondingly easier to lift (that is, the drop in pressure wouldn’t mean the top floor of tall buildings lose their water supply) ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [June 9, 2011, 7:34am UTC](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786/40 "2011-06-09T07:34:44Z")
In the longer run, the maximum sustainable size of arthropods may be slightly bigger. Your descendants may be pestered by larger cockroaches, for example. [Previous page](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786.md?page=1) [Next page](https://boards.straightdope.com/t/the-earth-now-has-95-of-its-former-gravity-what-happens/584786.md?page=3)