Why doesn't the math add up?
(media.greatawakening.win)
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The headline is wrong on its stated distance.
The shortest "shortest path distance" (straight line as measured from the Earth) between Earth and Mars is about 40M miles. The longest shortest path distance is about 250M miles. This depends on where the Earth and Mars are in their relative solar orbits.
These are straight line measurements though. The actual path for orbit change (delta V within the framework of solar and planetary gravitational fields) is along a curve because you can't just accelerate/decelerate the whole time. Thus you can't take a straight line path to get somewhere, thus the "shortest distance" is along the curve (geodesic) that gives the best delta V path within the gravitational field that is pulling you towards the sun and/or the planet when you get closer.
The distance of 120M miles is perfectly reasonable given these parameters along that curved path.
This orbital transfers along the respective orbits. Also including acceleration and deceleration, average speed is not cruising speed.
Still not enough miles
Because I did not read the article until later in this discussion, I did not realize which velocity the OP was stating. Please see my later replies in this discussion.
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Every article from CNN to Nat Geo to NASA says the perseverance TRAVELED 300,000,000 miles. Can you show me one source that backs up your claim?
Every article saying something is proof of Mockingbird media, not proof of the truth of something.
Here is something that should help to understand the basics. I only watched about a minute from the timestamp in this link. It should be sufficient to understand this curved path I am talking about.
I may not have explained it perfectly. The reason the path is curved is because the rocket engine has enough fuel for a limited burst of acceleration, thus the probe must rely on its initial velocity (whatever it achieves after its fuel is spent) to intersect with the Mars Orbit at the same time Mars reaches that point in its orbit.
But the probe is being accelerated towards the sun by gravity (away from the desired Mars orbit) thus the path that must be traveled by the probe is a curve (orbit) using only its initial velocity to achieve an intersection of its orbit (around the sun, that we gave it when we sent it off from Earth) and the orbit of Mars around the sun (that it has had for a very long time).
Everything you're saying sounds like pseudoscience gibberish to me. Does E=MC2 too?
...
I mean, if you want to throw every result of every experiment in all of time out the window then how can anything have meaning in any discussion about anything?
I have shown you orbital mechanics and how to achieve a transfer orbit in the simplest way possible. If you choose to say "that can't possibly be true because it doesn't fit my beliefs" without actually addressing the argument itself, there is no way to have a discussion. At that point you are just putting your fingers in your ears and saying "nananananana".
What kind of discussion can anyone have under those circumstances?
If you wish to address specifics in orbital mechanics I am happy to have those discussions. If you wish to present evidence that there are flaws in orbital mechanics (or really the entire idea of gravity, since orbital mechanics are just an extension of gravity) then please present your evidence. "Nananananana" does nothing for me, nor for anyone else. All it does is appease your cognitive dissonance in your apparent attempt to adhere to your current beliefs given the presentation of evidence to the contrary.
Yes
I'm not plugging my ears. I'm telling you that what you're saying doesn't explain anything and is loaded with bullshit and sophistry.
NASA: Vehicle traveled 300m miles. You: Vehicle didn't travel 300m miles because "delta V within the framework of solar and planetary gravitational fields"
Gibberish.
You are saying this, but you aren't addressing the part that is confusing to you, so I can't help explain it in a way that will help you to understand. Assuming that what I am saying is bullshit is an assumption. It would be more accurate (I think) to say that you don't understand what I am saying. That could be that you haven't put enough time into trying to understand, or that I have not explained it sufficiently well (did you even watch the video for the one minute I recommended?). I am not blaming you for not understanding. I don't know where the fault in your lack of comprehension lies. What it is not however is bullshit even if it is not correct. What I am saying is backed up by millions (billions? trillions?) of real experiments including many that I have done myself.
The vehicle obviously didn't travel 300m miles. You performed the calculation yourself. That headline is wrong. It also doesn't make sense from the evidence I have presented (even if you don't understand why). But a headline being wrong is no big deal. It's not even necessarily a lie. It's just wrong. People who write articles don't check the math of their headlines. They go to fact checkers (which are part of the International Fact Checking Network (IFCN)) to get their stories. No one is checking their math. No one cares about reporting reality. They only care about printing a story.
In no way does an incompetent reporter signify a breakdown in all of physics.
I said a lot more than that to help explain what that means. Suggesting this is all I said is purposeful out of context lying to support your statement that it was "pseudoscience" and "bullshit". I am trying to explain something that isn't even covered in physics until third year to someone who is suspicious of all of physics (which is reasonable, but not while also ignoring all of the evidence that supports the math).
Even on NASA.gov they state:
"NASA's Mars 2020 Perseverance rover mission has logged a lot of flight miles since being lofted skyward on July 30 - 146.3 million miles (235.4 million kilometers) to be exact. Turns out that is exactly the same distance it has to go before the spacecraft hits the Red Planet's atmosphere like a 11,900 mph (19,000 kph) freight train on Feb. 18, 2021."
This isn't just some random article with shady fact checking. NASA itself is claiming the vehicle traveled about 300m miles.
Regardless, the article said it went 300 million miles. That means in the delta it was on that point. Marh doesn't add up because they make zhit up.
I'm glad you cam explain the answer to the question for 119million Mile's but that wasn't the stated distance.
I will respond to this post to keep an important reply on the front page.
Yes, they do in fact state that the total path distance is 292M miles.
The missing key to understanding is what "velocity" means (or in this case speed). Speed is always relative to something else. In this case, the speed of the probe at 24,600 mph is relative to the Earth. The speed when it arrives at mars relative to Mars will be 11,900 mph. The speed along the curved path of 292M miles relative to the Sun (or really to any stationary observer) is the speed of the Earth around the sun times the relative angle of the probes velocity vector (after fuel is spent) + the speed of the probe relative to the Earth (24,600mph) = 52,000 mph relative to the curved path (or a stationary observer measuring the speed along the curved path). Which means it will take 233 days to reach the Mars orbit when Mars reaches the same point in its orbit. It will arrive with a speed of 11,900 mph relative to Mars.
Fun note: the speed according to the probe's point of view is zero.
This btw is also the speed according to your point of view when sitting at your desk; for the exact same reason.
Let me put it another way (to compliment my other response to this post).
If you throw a ball and you aim at the target directly, gravity will pull it down and you won't reach your target. Instead you throw it at an angle up so that when it reaches the target distance it will also be at the target height.
If you start with the same initial velocity (the strength of your arm) and you want to throw it further you need to adjust your angle up higher.
If you are on a train however, and you throw it with the same velocity it will travel much farther because the velocity of the train will add to the strength of your arm. You then have to adjust the angle lower to hit your target.
This isn't just an analogy to what the probe is doing, this is exactly what the probe is doing for exactly the same reason. They are "throwing" the probe, with the strength of a rocket, on a moving train (the Earth) to hit a moving target (Mars). Given the total strength of the arm (rocket) plus the velocity of the train (Earth) they calculate the angle they have to launch at to hit the moving target. This gives the start of the curved path, which will be a much longer path (along the path) than that calculated if you were to draw a ruler line from the thrower to the target.
The total velocity will be the strength of the arm (rocket) plus the velocity of the train (Earth) relative to someone standing on the ground (the Sun). But from the train (Earth) it will look much slower, because the train is moving in the same direction.
Great physics explanations ftw
You can read. Nasal isn't on Mars and never has been.
Not definitive but KSP, Scott Manley, Matt Lowne.
I wonder if the budget numbers add up as well
Add Earth's orbital velocity to the 26,400. It's a frame-of-reference problem.
Perseverance was headed away from Earth at 26.4 kMPH as we measure from the surface. Looking at it from a top-down perspective, Earth is headed around the sun at 67 kMPH, add the two.
From Mars' frame of reference, it has its own orbital velocity- 53 kMPH, which makes the Earth always appear as though it's headed toward or away from Mars at an additional 14 kMPH. Total delta-V 40.4 kMPH.
Also, the speed wasn't constant. Two additional burns happened during the journey- NASA noted it covered 1/2 the distance in 2/3 of the time.
The 26,400 is MPH not kilometers, but this explanation at least makes sense.
26,400 MPH = 26.4 kMPH. Same thing, fewer characters on a tiny phone keyboard. (k = 1000)
Sure, but what is the airspeed velocity of an unladen swallow?
A little gratuitous, but African or European? Besides, it's not a matter of how he grips the husk...
🐸👌❤
Because orbital mechanics is hard.
This is very normal. Here is a good site that explains and shows the path that it takes to Mars.
That link literally says it was a 309 million mile journey. But a 309 million mile journey is actually only a 120 million mile journey because.... Science!
"As of July 20, 2021, a total of 574 people from 41 countries have gone into space according to the FAI criterion (587 people have qualified when including the US Department of Defense classification). Of those 574, three people only reached a sub-orbital flight, 567 people reached Earth orbit, 24 traveled beyond low Earth orbit and 12 walked on the Moon.[7]" So on average about 12 people per year, nearly all military. 50 years ago, 12 people went 238,000 miles one way. Humans should be vacationing in 'outer space' by now at only 50 or 60 miles up. Politics? Or something else? Maybe NDGT can explain.
Did you even look at the trajectory?
Never mind.
Who cares about the trajectory? It's either a 309m mile trip or it isn't. If the trajectory you took made the trip shorter than 309m miles, why does it say it had a 309m mile trip?
They are not shooting out of a cannon going 24,600MPH in an instant and smashing into Mars at that speed either.
If you go to a drag strip and the cars top speed is say 208MPH why does it take so long to go only a 1/4 mile?
Uh, yes. They left earth's atmosphere going 24,600 mph according to NASA. Now I agree, they actually aren't doing that, but that is what they are claiming.
🤷♂️ https://mars.nasa.gov/imgs/mars2020/spacecraft/Mars_Perseverance_Trajectory_0817.jpg
You do you.
Anyone whos played kerbal space program for at least 30 minutes knows you cannot just accelarate in a single direction towards something in space, you have to work within the confines of this little thing called orbital mechanics
Because it's all part of their scam is why. How dare you use your brain!
Because the velocity was not constant. The spacecraft was accelerating during its cruise phase to Mars. The velocity relative to Earth at launch was 24,600mph. When it approached Mars, its velocity relative to Earth was 64,123mph.
That's a roughly 8.193mph^2 rate of acceleration over that duration on a curved trajectory. You also have to consider the relative speed of Mars' orbit...
So the distance over time does add up, but you need to consider the movements of other celestial bodies and use some more advanced math to get there,
The moon is flat
🙃 joking
Posh.
You're forgetting that the Earth-Mars distance changes with the orbit. At it's maximum these numbers are impossible. At the minimum it is very possible.
Would NASA launch a probed on a trajectory when it's short or when it's long?
Reconcile.
-- Q123_Fuck my math
I'm seeing a lot of explanations that don't make sense to me.
To me what your calculations are showing is that if it were to travel at the velocity stated in the article the entire duration of the trip, the total distance covered would be 120M miles.
I'm not an astrophysicist, but comparing that to the 300M number you're talking about seems reasonable just because of acceleration and deceleration.
300 million? That's a weird number to choose. Especially when Anons can refute it.
Probably average or something.
I am planetary-distance challenged and too bored to research it.
I chose 300M because that's what is stated in the headline of one of the articles that is the basis of this post.
I think when OP says why is A != B, I should talk about A and B, not C.
Yeah, accelerating to more than the stated speed would account for the discrepancy, but it's almost three times the distance, so that would mean the vehicle was travelling 75,000ish MPH or more and managed to also reverse this speed and land safely hundreds of millions of miles away. Doesn't that seem kinda fantastical to you? That's like Mach 100.
Oh yeah, it definitely sounds insane. Is it actually possible? I'm not sure. I know that with almost no gravitational force or air resistance in space to overcome, that accelerating should be easier. But I've always struggled with how any propulsion works in space with no air to push against...
The force that makes a rocket go up has nothing to do with the exhaust pushing against air. Newton's Third Law of Motion: Any force applied to an object will be subjected to an equal and opposite force from the object.
Chemical combustion in the engine creates an outward force and pressure that must escape through a nozzle. The engine itself is fixed, so that forward force is transferred to the rocket body. If the force is enough to overcome inertia, the rocket accelerates (First Law). How much force depends on the mass of the combustion products and the speed at which they travel (Second Law).
It's like firing a rifle. It has recoil, whether your shoulder is there to push against or not. That recoil is the sum total of the force expended pushing the bullet forward. Small bullet, big velocity. Big human, small velocity.
In a rocket, though, the bullets are much smaller (molecules) but there are trillions per second and traveling nearly 100,000 MPH leaving the nozzle.
Best explanation I've ever had, thanks! Molecules as trillions of bullets is a great vizualization.
About relativity to an object. 24k leaving earth becomes + earths speed through space, like the trow ball from train examples above. Adds both speeds. Read the great explanation above. OP got schooled with real physics.
Yeah that probably accounts a good amount of the difference. The article was also only 2 days after launch so it might not have been finished accelerating either.
I didn't even think about that.
Ph, I'm sure it's just a bend in the atmosphere or some shit assed excuse like always.
“Math is hard”
Barbie NASA
Mars is a light in the sky, not a floating rock governed by fictional "gravity".
Check out The Thunderbolts Project on youtube, it's all electric.