Re: A revolution in thought
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Originally Posted by davidm
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Originally Posted by peacegirl
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Originally Posted by davidm
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Originally Posted by peacegirl
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Originally Posted by davidm
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Originally Posted by peacegirl
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Originally Posted by specious_reasons
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Originally Posted by peacegirl
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Originally Posted by davidm
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Originally Posted by peacegirl
Who said the sound of his voice is traveling 186,000 miles per second?
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… because the sound of his voice is traveling 186,000 miles a second.
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It’ right there in the bit you quoted.  |
You are right. He made a mistake by using light as the measurement for sound. It doesn't change the point he was making though, nor does it make his claim that the eyes are not a sense organ incorrect. Keep your eye on the ball, which is all I ask for and don't let an error deter you. Whether sound travels at 186,000 miles a second or 355 m/second, doesn't change the concept at all. If he is right, our gaze is instant while sound takes time. That's the point he was making. it's trivial unless you want to use this error to condemn his proposition because you don't want him to be right. But thanks for bringing this to my attention.  |
Sound didn't travel from the moon through airless space. They talked to the Earth via radios, which uses electromagnetic radiation, or light.
You and/or Lessans are saying you'd see the astronauts lips move on the moon and hear it on the radio 3 seconds later. That is consistent with the incorrect notion that we see things instantly.
So you don't have to change that passage unless you want to remove it because "the eyes are not a sense organ" is literally the dumbest thing in that book. |
No it isn't. You're only trying to confirm that he was wrong without understanding why he made the claim. That's the only way to figure out whether he was right. According to their explanation, there is a delay in converting speech to radio waves which causes a 2 second delay. But are they correct?
When astronauts stood on the Moon during the Apollo missions, they encountered a fascinating phenomenon: they could see things instantly, but there was a delay in hearing sounds. Let’s break down why this happened:
Visual Perception:
When an astronaut looked at the lunar surface or another astronaut, light traveled from the object to their eyes at the speed of light (approximately 299,792 kilometers per second).
Since the Moon has no atmosphere to scatter or slow down light, visual information reached their eyes instantly.
So, when an astronaut waved their hand or moved, their fellow astronauts could see it immediately.
Lack of Atmosphere:
The Moon lacks an atmosphere, which means there is no medium for sound waves to travel through.
On Earth, sound waves propagate through air, water, or other materials. But on the Moon, there’s nothing to carry sound.
Without air molecules to vibrate and transmit sound, any spoken words or noises made by astronauts remained silent.
Communication via Radio Waves:
Astronauts communicated using radio waves.
They wore helmets with built-in microphones and speakers.
When an astronaut spoke, their voice was converted into radio waves and transmitted to other astronauts or mission control on Earth.
These radio waves traveled at the speed of light, just like visual information.
However, the processing time for converting speech to radio waves and transmitting them introduced a slight delay.
As a result, there was a 2-second lag between an astronaut speaking and their colleagues hearing it.
In summary, the absence of an atmosphere on the Moon prevented sound waves from traveling, while radio waves allowed astronauts to communicate despite the delay. It’s a fascinating interplay between physics and technology!
I wonder what would happen on a mission to Mars. Would the conversion of sound to radio signals (accounting for the time lag and adjusted) cause ground control to see the astronauts 0.13 seconds later, or would they see the astronauts instantly (with a powerful telescope here on Earth) but hear their speech with a noticeable delay of 0.13 seconds? How would they reconcile this when the conversion to speech only took two seconds, not 0.13?
Given the speed of light, let’s calculate how long it would take to see an astronaut on Mars from Earth.
Distance to Mars: The average distance between Earth and Mars varies due to their elliptical orbits. On average, it’s approximately 225 million kilometers (140 million miles) when they are closest to each other.
Speed of Light: The speed of light in a vacuum is approximately 300,000 kilometers per second (186,282 miles per second).
Time Calculation: Using the formula Time = Distance / Speed, we can find the time it takes for light to travel from Mars to Earth: [ \text{Time} = \frac{\text{Distance}}{\text{Speed of Light}} ] [ \text{Time} = \frac{225 \times 10^6 , \text{km}}{300,000 , \text{km/s}} ] Calculating this: [ \text{Time} = 750 , \text{s} ] Therefore, it would take approximately 0.13 seconds to see an astronaut on Mars from Earth, assuming the speed of light as the only factor1.
Keep in mind that this calculation doesn’t account for other factors like signal transmission delays or the time it takes for the astronaut’s image to reach our eyes. In reality, it would be slightly longer due to these additional factors. |
peacegirl, from where did you steal the above?
Note that it contradicts you. The writer claims it would take 0.13 seconds to see an astronaut on Mars from earth. 0.13 seconds IS NOT INSTANTANEOUS, peacegirl. Not.
But it is still wrong. The delay in seeing the astronaut on the moon would be considerably greater, because Mars, ON AVERAGE, is 12.72 light minutes from earth. We use the AVERAGE distance, because the ACTUAL distances between the two planets vary over the course of the year.
What this means is that ON AVERAGE, it would take 12.72 minutes to see an astronaut on Mars from earth.
The statement that lunar astronauts saw themselves instantly is false.
A radio is a device for converting electromagnetic waves (light) into mechanical waves (sound). This would indeed introduce a slight time differential in optical detection and radio detection, but so slight no one would notice. |
That's why a more accurate result would come from Mars since there is a larger gap in the time it would take for the radio signals to get here. If we got a view of Mars at the same time the radio signals were detected, then we would be seeing Mars in delayed time. If the telescope viewed Mars before the radio signals got to mission control 0.13 seconds later, the view of Mars would not be delayed, but instantaneous. |
We’ve already does this experiment many times, peacegirl, including on Mars with Rovers.
As noted, the 0.13 time delay is wrong. The average delay is 12.72 minutes. But even if it were only 0.13 seconds, you, in your charmingly daft way, still seem not to have comprehended that the time-delay figure CONTRADICTS you. |
Is there a way for us to see the result of this; ie., the signal being transmitted and seeing the Rover on Mars at the exact same time that the signal arrives? I'm sure Nasa would show this, right? |
Right, there is a delay. We’ve gone over this many times with you, including how NASA takes into account delayed-seeing to plot spacecraft trajectories to Mars. This because where Mars APPEARS to be in the sky, is not where it actually IS, due to delayed-time seeing. We’ve gone over and over this. In one ear, out the other. |
The course correction doesn't have to do with the delay of light. It has to do with the planet's own trajectory, where its actual position changes over time.
When embarking on a journey to Mars, precise trajectory adjustments are essential. Let me explain why:
Interplanetary Navigation:
Getting to Mars isn’t as straightforward as aiming directly at the planet. Unlike a stationary target, Mars orbits the Sun, and its position changes over time.
To hit the moving target accurately, spacecraft must be inserted into their interplanetary trajectories at precisely the right moment. Imagine throwing a dart at a bullseye that’s constantly shifting1.
Course Corrections:
During transit, probes must make multiple trajectory corrections to ensure they arrive at Mars when it’s in the right position.
These adjustments involve firing small onboard rockets to fine-tune the spacecraft’s path. Think of it as recalibrating your aim during a long-distance archery competition2.
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