212 réponses à ce sujet

[BombThatDeadGuy]

One security upgrade making Omni-Gel completely useless.

[The Night Mammoth]

David7204 wrote...

Here's a little something straight from Wikipedia:

"Meteoroids travel around the Sun in a variety of orbits and at various velocities. The fastest ones move at about 42 kilometers per second (26 miles per second) through space in the vicinity of Earth's orbit. The Earth travels at about 29.6 kilometers per second (18 miles per second). Thus, when meteoroids meet Earth's atmosphere head-on (which only occurs when meteors are in a retrograde orbit such as the Eta Aquarids, which are associated with the retrograde Halley's Comet), the combined speed may reach about 71 kilometers per second (44 miles per second). Meteoroids moving through Earth's orbital space average about 20 km/s."

The Space Shuttle enters atmosphere at about 8,000 meters per second. 8 km/s.

As we can clearly see in the ME 2 intro, Shepard is quite close to the planet and isn't initally moving towards it.

 

She is. 

In contrast to the space shuttle and meteorids, the only speed s/he would attain is speed gained from the planet's gravity. The planet's gravity is not going to suck Shepard in at anything close to a speed of 20 kilometers per second.

Speed isn't everything. Alchera is noted to have a thick atmosphere, and there's still the little issue of hitting the planet's surface at the end of the fall. 

Even if Shepard doesn't completely burn up, she's going to be burnt, severely, and then obliterated on impact 

[Sebby]

Shepard's death/Lazarus was so needless to top it all off. The same reset button effect could have been had with him simply being in a coma for two years but that wouldn't have been dark and edgy enough I suppose.

Modifié par Seboist, 04 février 2013 - 06:15 .

[Smeffects]

The list would be so long id need 3 pages by myself.

[k.lalh]

David7204 wrote...

Here's a little something straight from Wikipedia:

"Meteoroids travel around the Sun in a variety of orbits and at various velocities. The fastest ones move at about 42 kilometers per second (26 miles per second) through space in the vicinity of Earth's orbit. The Earth travels at about 29.6 kilometers per second (18 miles per second). Thus, when meteoroids meet Earth's atmosphere head-on (which only occurs when meteors are in a retrograde orbit such as the Eta Aquarids, which are associated with the retrograde Halley's Comet), the combined speed may reach about 71 kilometers per second (44 miles per second). Meteoroids moving through Earth's orbital space average about 20 km/s."

The Space Shuttle enters atmosphere at about 8,000 meters per second. 8 km/s.

As we can clearly see in the ME 2 intro, Shepard is quite close to the planet and isn't initally moving towards it. In contrast to the space shuttle and meteorids, the only speed s/he would attain is speed gained from the planet's gravity. The planet's gravity is not going to suck Shepard in at anything close to a speed of 20 kilometers per second.

Well let's try some physics shall we?

No matter what his horizontal velocity is, the acceleration due to gravity (on Earth) is always -9.81m/s^2. For simplicity's sake let's assume that the acceleration on this planet is -10m/s^2, and it's atmosphere is the same as it is on Earth.

So firstly let's think about how high we are. The space shuttle orbits at around 350km above the planet's surface. using the formula vf = 2ad this would mean that Shepards final velocity is 7 000 km/s when he hits the ground (discounting air friction.)

With the assumption that the force acting on Shepard is 1000N (assuming he weighs 100kg) due to gravity. Using the formula Vt = sqrt(2mg/pac) we can find his final velocity. But since we do not have the values of p and ac we can use the shuttle as an example for terminal velocity. Mach 22.4 is the speed of the shuttle which is 295.1 m/s. The Columbia broke up on re-entry, and was not traveling anywhere near Mach 22, as it was already in the atmosphere. Shepard isn't areo dynamic, and exposes a lot of surface area. The force of friction acting on him would be around 700N at that speed. And this is constant force. Shepard should be dust. The only possible explanation for his survival would be if his armor was super resilient, but keep in mind. Meteors the size of a car would completely burn up. well before entering the lower reaches of the atmosphere.

Point is, your argument is invalid. Unless Shepard's armor's heat capacity can withstand 9000 degrees Celsius for 15 mins, he would be destroyed.

[David7204]

No. First of all, Alchera's atmospheric pressure is only .86 atm, as opposed to 1 atm for Earth. So it's less thick. Even if that wasn't true, since drag is directly related to the density of the fluid, the two would at least somewhat cancel each other out. I can't say to what degree.

[k.lalh]

David7204 wrote...

No. First of all, Alchera's atmospheric pressure is only .86 atm, as opposed to 1 atm for Earth. So it's less thick. Even if that wasn't true, since drag is directly related to the density of the fluid, the two would at least somewhat cancel each other out. I can't say to what degree.

If there is less drag, final velocity would be higher. Less chance of burning up, but greater chance of being obliterated on impact.

[David7204]

Okay, first of all, the correct formula is V^2 = 2Ad. Not V = 2Ad.

Secondly, I don't know what the hell 'pac' is.

Thirdly, the Columbia was traveling at 8,000 m/s. Not 295.1 m/s. I don't know where you got that number.

Are you sure you know what you're talking about?

[k.lalh]

David7204 wrote...

Okay, first of all, the correct formula is V^2 = 2Ad. Not V = 2Ad.

Secondly, I don't know what the hell 'pac' is.

Thirdly, the Columbia was traveling at 8,000 m/s. Not 295.1 m/s. I don't know where you got that number.

Are you sure you know what you're talking about?

Sorry 295.1 m/s is the speed of Mach 1 at the altitude at 45000 feet. Mach 22.4 would be ~6600m/s

Sorry yah your formula is correct. Auto Correct.

But if you do apply that 8000 m/s, that would still make your argument invalid, as that would have even greater drag.

PAc is fluid density x drag coefficient .

Modifié par k.lalh, 04 février 2013 - 06:34 .

[David7204]

It doesn't matter half a damn what speed the shuttle orbits. The only speed we care about is the atmospheric entry speed. Which is 8,000 meters per second. And that's meters. Not kilometers.

Also, that formula relates the force of DRAG, not the force of gravity. And it's not the final velocity either. It's the instantaneous velocity. They're only the same at terminal velocity, by which time any damage that would have been done would already be done. Skydivers don't burn up at terminal velocity.

Look, this is just a mess.

Modifié par David7204, 04 février 2013 - 06:38 .

[dreamgazer]

How about the massive, mind-controlling alien root structure that kept crapping out cloned green asari?

[Smeffects]

Mass effect fields solves problem in the galaxy guys, Relax.

Remember when Luke dropped down to escape from Darth Vader? He got sucked into this tube or what ever, pretty sure he would be a splatter at the speed he was going when he entered that thing. Thats why they are called science fictions, not science.

Science fiction is a genre of fiction with imaginative but more or less plausible content. The settings for science fiction are often contrary to consensus reality, but most science fiction relies on a considerable degree of suspension of disbelief.

Hard science fiction, or "hard SF", is characterized by rigorous attention to accurate detail in quantitative sciences, especially physics, astrophisics, and chemistry, or on accurately depicting worlds. So we can rule out mass effect from "Hard SF"


Space Opera is adventure science fiction set in outer space or on distant planets. The conflict is heroic, and typically on a large scale. Space opera is sometimes used pejoratively, to describe improbable plots, absurd science, and cardboard characters. Looks like we have a winner

Modifié par Smeffects, 04 février 2013 - 06:55 .

[k.lalh]

@David7204

I also think that, since much larger objects, burn up, and are entering the atmosphere at a steeper angle, where there is less exposure to friction, and are more aerodynamic, the probability of Shepard being more than just dust, is highly unlikely. You yourself stated the airspeed of which Columbia entered the atmosphere. Shepard would enter at near the same velocity, as the atmosphere is of similar structure/composition but less dense.
If Shepard hit the ground without an atmosphere to slow him down to say, Mach 2, he would hit the ground at 7000km/s, which would obliterate him. A deceleration from a speed of 8000m/s to ~500m/s over a time period of say 5 minutes would place tremendous strain on him. I'm a bit rusty on my math, (there's a reason why I am in the field of biology, not applied physics), so I'm not going to calculate exact values.

This problem can be solved if his armor was made of some kind of super material, similar to graphene. That could somehow protect him from temperatures approaching 9 000 degrees C (hotter than the sun's surface). However, if his armor couldn't do that. He'd be dust.

Edit: No point arguing this. My point is, unless his armor is incredibly durable, he's toast

Sorry about dragging that out David.

And Drag is what's causing friction, which is acting opposite to gravity. Friction causes heat. With that much time at Vf, he would burn up, just making that clear, why the drag formula needs to come into play.

Modifié par k.lalh, 04 février 2013 - 06:58 .

[Inquisitor Recon]

The space terminator with three eyes and Shepard's resurrection. Why they couldn't make him just critically injured instead of this scenario where his frozen corpse slams into a planet at hypersonic speeds, yet is somehow salvageable.

[David7204]

There are about a half dozen mistakes in that paragraph.

First of all, no, Shepard would not enter atmosphere at the same speed of the Columbia. The speed at which an object enters atmosphere has utterly nothing to do with the composition of the atmosphere.

Secondly, Alchera's atmosphere has a simliar "structure/composition" to Earth's? By 'similar structure', you mean it has gas surrounding a large mass, which is any and every atmosphere? The composition sure as isn't the same, since it's methane and ammonia, not nitrogen and oxygen. So that's wrong.

Thirdly, you're doing a very sloppy job with meters and kilometers. Think about what you just said. You just said Shepard is going to hit the ground at 7,000 kilometers per second. Do you know what 7,000 kilometers per second is? It's over 2% of the speed of light. Do you know how ridiculous that number is?

Forthly,  Shepard is not going to burn up after a certain time at terminal velocity, or as you put it, 'Vf.' As I said, skydivers do not burn up at terminal velocity. And it doesn't matter how long you're in terminal velocity, that's not going to change.

Fifthly, "8000m/s to ~500m/s over a time period of say 5 minutes" is an acceleration of only 25 m/s/s or so. That's only a 2.5 G-force. We have rollarcoasters that go up to 4.5 G force, and fighter pilots probably take a hell of a lot more.

Modifié par David7204, 04 février 2013 - 07:12 .

[k.lalh]

David7204 wrote...

There are about a half dozen mistakes in that paragraph.

First of all, no, Shepard would not enter atmosphere at the same speed of the Columbia. The speed at which an object enters atmosphere has utterly nothing to do with the composition of the atmosphere.

Secondly, Alchera's atmosphere has a simliar "structure/composition" to Earth's? By 'similar structure, you mean has surrounding a large mass, which is any and every atmosphere? The composition sure as isn't the same, since it's methane and ammonia, not nitrogen and oxygen. So that's wrong.

Thirdly, you're doing a very sloppy job with meters and kilometers. Think about what you just said. You just said Shepard is going to hit the ground at 7,000 kilometers per second. Do you know what 7,000 kilometers per second is? It's over 2% of the speed of light. Do you know how ridiculous that number is?

Forthly,  Shepard is not going to burn up after a certain time at terminal velocity, or as you put it, 'Vf.' As I said, skydivers do not burn up at terminal velocity. And it doesn't matter how long you're in terminal velocity, that's not going to change.

Density has everything to do with Vf

I equated it to earth for sake of simplicity Methane first of all would ignite with the surface temperature shep is achieving.

It's 83 km/s...forgot the square root. my bad.

[David7204]

Density has everything to do with the terminal velocity and nothing to do with the atmospheric entry velocity.

[Deathsaurer]

This argument is silly. Jacob said Shepard was nothing but meat and tubes. That was not a friendly impact.

[k.lalh]

David7204 wrote...

Density has everything to do with the terminal velocity and nothing to do with the atmospheric entry velocity.

I said final velocity.

Entry velocity is zero, but it would come close to say 75 km/s which would be horrific on impact.

Modifié par k.lalh, 04 février 2013 - 07:14 .

[David7204]

k.lalh wrote...

...You yourself stated the airspeed of which Columbia entered the atmosphere. Shepard would enter at near the same velocity, as the atmosphere is of similar structure/composition but less dense

You said entered.

Modifié par David7204, 04 février 2013 - 07:16 .

[k.lalh]

David7204 wrote...

 The only speed we care about is the atmospheric entry speed. Which is 8,000 meters per second. And that's meters. Not kilometers

We're arguing about semantics. This isn't productive. You should understand what kind of forces are acting on Shepard, and how brutal his impact would be. If it wasn't for plot armour, or regular armour for that matter, he'd be dust.

[David7204]

No. I understand perfectly what's going on. You're the one who's getting confused.

Shepard's atmospheric entry speed is not going to be zero. Nor is it going to be 8,000 meters per second. Nor is it going to be 7,000 kilometers per second.

[k.lalh]

David7204 wrote...

No. I understand perfectly what's going on. You're the one who's getting confused.

Shepard's atmospheric entry speed is not going to be zero. Nor is it going to be 8,000 meters per second. Nor is it going to be 7,000 kilometers per second.

Fine. I obviously can't prove my point. Why would Shepard not burn up?

Also Shepard's vertical velocity would be close to zero. It's his horizontal velocity that would be higher. Gravity only acts on Vertical velocity, and his entry velocity would be his orbital speed.

His VF or final velocity, which I have stated before, is going to be ~ less than 83 km/s

Modifié par k.lalh, 04 février 2013 - 07:27 .

[Asch Lavigne]

TimtheEnchanter wrote...

Kasumi's mission in ME2.
One of the most famous humans in history goes undercover on the offchance that nobody will recognize her/him.
Heck, let's even bring a statue of Saren to refresh their memories.

Ha! I always wondered about that.

Heck, hiring a thief for a "military" operation to go and kill a whole race of people made no sense to me either. I get she was a tech expert, but unless we want to steal back the colonists, a thief, really?

[David7204]

Let's look at that number.

You say Shepard would be moving 75 km/s?

V^2 = 2ad

Alchera's gravity is .85g.

5,625,000,000 = (2)(.85)(9.81)(d)

d = 337,000,000.

These numbers are just ridiculous. A simple equation shows that to attain a speed of 75 km/s, Shepard would have to fall over 330 million meters. 330,000 kilometers. The radius of Earth is 6378 kilometers and you're saying Shepard falls 330,000 kilometers from the Normandy to the ground.

And that's with zero drag and a constant gravitational fireld equal to the surface gravity, neither of which would be present.

Modifié par David7204, 04 février 2013 - 07:29 .