Shuttle lift off if no Gravity

[HebaruSan]

4 minutes ago, Snark said:

Unfortunately, the star tracker would be absolutely useless for telling them where the shuttle is or how fast it is currently going.  It will tell them the absolute orientation of the shuttle, that's it.

How do they know what their current XYZ coordinates are, or how fast they're going?

Did it sound like I was advocating that the shuttle would be fine? Because I just thought the questions were interesting, and looking up this stuff is fun. (I initially remembered hearing that the Saturn V also had a star tracker, which blew my mind at the time, but I couldn't find any info on that at all.) I'm sure the shuttle would engage its legendary flight abort system, a.k.a. "everybody dies."

[KerikBalm]

OP needs to do some major clarification of what is going on here. From the first post, it sounded like there would be so sy-fi gravity nullification device to improve the shuttle's capability. 

Quote

 ... the space shuttle as an example, how much fuel would be saved if gravity stopped at the moment of liftoff for ... one full minute?

- but we have debates here about what happens if gravity were to suddenly disappear (in the vicinity of earth).

I tried to give the OP as much credit as possible and assume this would just affect the shuttle, but alas, that isn't the case:

Quote

11 hours ago, HebaruSan said:

Are we talking all gravity? Is the atmosphere affected?

Yes, all gravity in the vicinity of earth, including the moon

And that right there... leads to a massive worldwide catastrophe... civilizations would collapse over this. As noted in the 1 minute scenario... people and objects would be falling from up to 60 meters in this scenario... all over the world (well, not at the poles, and less as latitude decreases). World wide earthquakes would occur orders of magnitude larger than anything we've ever seen. I doubt there would be a building left standing, anywhere...

There'd probably be massive volcanic eruptions as well. Massive ecosystem collapse would ensue... and the OP is asking about fuel savings on a launching spacecraft (that would amount to, at best, 1/9th of the dV required to get to orbit)...

Ummm.... no...

The parameters of this thought experiment need to be better defined, otherwise this is pointless

[NoGravity]

7 hours ago, KerikBalm said:

OP needs to do some major clarification of what is going on here. From the first post, it sounded like there would be so sy-fi gravity nullification device to improve the shuttle's capability. 

- but we have debates here about what happens if gravity were to suddenly disappear (in the vicinity of earth).

I tried to give the OP as much credit as possible and assume this would just affect the shuttle, but alas, that isn't the case:

And that right there... leads to a massive worldwide catastrophe... civilizations would collapse over this. As noted in the 1 minute scenario... people and objects would be falling from up to 60 meters in this scenario... all over the world (well, not at the poles, and less as latitude decreases). World wide earthquakes would occur orders of magnitude larger than anything we've ever seen. I doubt there would be a building left standing, anywhere...

There'd probably be massive volcanic eruptions as well. Massive ecosystem collapse would ensue... and the OP is asking about fuel savings on a launching spacecraft (that would amount to, at best, 1/9th of the dV required to get to orbit)...

Ummm.... no...

The parameters of this thought experiment need to be better defined, otherwise this is pointless

OP, Here.

The premise is that gravity would stop for a short period of time for up to one minute in the vicinity of the earth but not as far out as the other planets.

The multiple episodes of no gravity, quantity as yet undetermined, would occur over a period of time and increase from fractions of a second to the one minute scenario.  The cause of this will be explained in the story. The one minute scenario is the last episode of no gravity. I am not intending to kill off everyone in an end of the world sense and don't think that is necessary which will create tension in the story.

Anyone wanting to be a beta reader can message me privately.  You can do that right? 

Thanks to everyone. I have learned a lot from the discussion. 

Again as a newbie, I know I can't play that card too often, but where would be the appropriate place to ask the question. Why  didNASA turned off all the Apollo era ALSEP data streams at one time on 30 SEP '77?

Thank you!

 

 

[YNM]

9 hours ago, Snark said:

Unfortunately, the star tracker would be absolutely useless for telling them where the shuttle is or how fast it is currently going.  It will tell them the absolute orientation of the shuttle, that's it.

How do they know what their current XYZ coordinates are, or how fast they're going?

Location may be done with this (although so far, only on deep space probes). Another way for round the Earth location is accounting time and horizon as well, just like ol' sailors. For velocity, this is common.

[Snark]

42 minutes ago, YNM said:

Location may be done with this (although so far, only on deep space probes).

That seems out of context to me.  You're saying that in the middle of a shuttle launch, while everything's shaking and rumbling, when something suddenly goes haywire with the Earth's gravity, they're going to use parallax to, 1. notice that something's wrong, and 2. fix it quickly?  That seems... really unlikely.

To be clear, the context here is:  the shuttle is in the middle of a launch and suddenly its trajectory is off because of a gravity failure.  Is there any way that the shuttle astronauts (or the automated systems on the shuttle) would know that anything's wrong, and have the necessary data to be able to correct the problem, even assuming that it's physically possible to do so given the control mechanisms available?

[KerikBalm]

6 hours ago, NoGravity said:

The multiple episodes of no gravity, quantity as yet undetermined, would occur over a period of time and increase from fractions of a second to the one minute scenario.  The cause of this will be explained in the story. The one minute scenario is the last episode of no gravity. I am not intending to kill off everyone in an end of the world sense and don't think that is necessary which will create tension in the story.

You may not be intending to.... but physics basically says that you would

[p1t1o]

14 hours ago, KerikBalm said:

OP needs to do some major clarification of what is going on here.

I think its fine. Its just that most interpretations resemble a classic "anti gravity" drive, which is fine for sci-fi, but not exactly that new or exciting. Discussing more dramatic circumstances is more stimulating

 

7 hours ago, NoGravity said:

OP, Here.

The premise is that gravity would stop for a short period of time for up to one minute in the vicinity of the earth but not as far out as the other planets.

The multiple episodes of no gravity, quantity as yet undetermined, would occur over a period of time and increase from fractions of a second to the one minute scenario.  The cause of this will be explained in the story. The one minute scenario is the last episode of no gravity. I am not intending to kill off everyone in an end of the world sense and don't think that is necessary which will create tension in the story.

Anyone wanting to be a beta reader can message me privately.  You can do that right? 

Thanks to everyone. I have learned a lot from the discussion. 

Thinking of unusual situations is great for sci-fi, but your idea might need a bit of tweaking to avoid massive-earth-death. Also, the effects of turning off gravity would be so far reaching that it would take a lot of the book just to describe it properly. In terms of the story, it might be worth thinking of limiting, or "modulating" the scenario a little so that your dramatic elements are not overshadowed by what the reader imagines is happening elsewhere.

OR

Go full-hog, turn off earth gravity for a significant time and base the book on what happens.

 

7 hours ago, NoGravity said:

Again as a newbie, I know I can't play that card too often, but where would be the appropriate place to ask the question. Why  didNASA turned off all the Apollo era ALSEP data streams at one time on 30 SEP '77?

Thank you!

From the ALSEP wiki page:

"The ALSEP system and instruments were controlled by commands from Earth. The stations ran from deployment until they were turned off on 30 September 1977 due primarily to budgetary considerations. Additionally, by 1977 the power packs could not run both the transmitter and any other instrument, and the ALSEP control room was needed for the attempt to reactivate Skylab. ALSEP systems are visible in several images taken by the Lunar Reconnaissance Orbiter during its orbits over Apollo landing sites."

[RCgothic]

I think people would fall from a height much greater than 60m. Centripetal acceleration alone may put people that high, but remember that at the point gravity turns off everything on Earth's surface is pushing down with enough force to generate 1g. That force doesn't stop just because gravity does.

Assuming that it takes 5cm for the average person to lose contact with the ground, they'd gain an additional m/s just through this spring force. That's an additional 60m height over a minute for anyone not inside, even at the poles.

Snark is also right about the guidance issues for a shuttle due to the lack of inertics. It's not going to know it has an extra accelerating except by atmospheric wind speed. Possibly not fatal to a mission depending on what stage of the launch you're at, but it could make max Q very dicey.

Over 60s the maximum possible dv gain is about 600m/s, which is not an enormous amount. And you'd actually gain less speed due to additional wind resistance and the fact that once you've turned you aren't directly fighting gravity.

[Nibb31]

Even if gravity was cancelled for a minute, trains would derail, cars would crash, planes would fall out of the sky, rivers would stop flowing and cause major floods, dams, bridges and major buildings would suffer serious damage. Anything that uses gravity for fluid circulation or convection for cooling would break (this includes most generators, hydro dams, nuclear power plants...). 

More dramatically, the Earth's orbit would be durably modified (it would fling off on a tangent, then find itself in an excentric orbit when gravity is switched on again). The result of such an orbit would be huge climate variations, which would influence the polar caps, sea levels, crops, ecosystems, and resulting in millions of deaths.

As for the Shuttle, it would likely crash too, like anything that relies on gravity, since most of its sensors and software controls would be wrong, making it uncontrollable. It would probably endup going off-course, slipping out of the airflow, and breaking up due to aerodynamic forces.

Edited February 23, 2017 by Nibb31