# QuestionClarification of telescope zooming or its chronological accuracy (to be continued)

#### Captain Nemesis

Astronomers say that they didn`t notice indications of extraterrestrial civilization anywhere around.

I wonder can we actually see aliens with our telescopes. Why do I ask this question? Because light from distant objects travels very long to reach us. Let us take in the consideration exoplanet Kepler 452b which is aprox. 1400 ly from Earth. We can use anything distant for this purpose. At the present moment we see it as it was 1400 years ago. Therefore we must wait 1400 years to see how it looks now. Or we can use something which is called optical magnification.

I have found data for Earth`s best magnification telescope: Keck 17500x.
Others fall much behind: Subaru 7500x, Yale 4850x, Hubble 2880x, etc.

I can not find Webb optical magnification power nor focal lenght of its eyepiece. The only fact I found is comparison with Hubble stating that Webb can see 10 to 100 times better. I guess it means that it has 28.800 to 288.000 optical power. Please correct me here or wait up-date to this post.

Until I find exact optical power data for Webb, let`s take Keck`s optical magnification of 17.500x and divide 1400 ly with 17.500. We should be able to see 1400 ly / 17.500 = 88.537.508 AU or how Kepler 452b looked like before 0.08 year or one month.

If Webb has the 288.000 optical power than we should see Kepler 452b like it is 0,00486 year or 1.7 day ago.

Have in mind that we are talking of infrared imaging not visual. Every other spectrum than visible must be properly translated. I mean, heat signature is not the picture of the object. It is just the heat signature of the object. From that we must extract how the image real looks like.

My question: does telescope zooms on true or apparent image? If it zooms on true image then we will have almost accurate representation from the time perspective. If it zooms on the apparent image, the light that is 1400 years old in our Kepler 452b case, then we actually have no enlargement in chronological sense but only image quality sense or optical resolution.

1400 ly minus 1.5 million km is real approach with chronological equivalent. Both are insignificant without optical zooming.

If we are zooming apparent image then we will need to send spacetelescopes to travel the desired direction even more, much more since 1.5 million km is nothing in astronomical terms.

The angular (optical) magnification is the ratio between focal lenght of an objective lens or primary mirror and focal lenght of the eyepiece. In astronomy we say angular, instead optical like in ordinary photography, because the sizes of celestial distances and objects are given in terms of their angular diameter as seen from the Earth.

Hubble`s telescope primary use was for gathering electromagnetic radiation from the UV and visible spectrum only. Infrared sensor was added later. Joined wavelenght is ranging from 0.1 to 2.5 microns, particularly: 0.1 - 0.4 UV and 0.4 - 0.7 visible light, 0.7 - 2.5 infrared.

This is good EM diagram:

New NASA space telescope James Webb will have magnification power of ????? with second major difference that it has much better and originally implanted infrared sensor. Infrared spectrum covers 1 - 1000 microns (0.001 - 1 millimeter). Webb goes to 28.5 microns which is near to mid IR spectrum. For comparison, Herschel (ESA space telescope named after discoverer of IR spectrum) observed from 60 to 500 microns or mid to far IR spectrum.

Hercshel and Webb observe(d) Universe before the visible light was created peering deep and deeper into the thermal traces of the Big Bang.

Another major difference is location: Hubble orbits the Earth at about 547 km. Webb will be positioned at L2, 1.5 million km from Earth following it in the orbit around the Sun, just like Herschel was. This location balance gravity effects between Sun and the Earth, reducing fuel consumption and also enabling telescope to block heat interference from the previously mentioned sources hiding behind Earth and using large, tennis court size sunshield.

Both Webb and Hubble telescopes are NASA & ESA collaboration. Herschel was ESA solely.

Sources:

Short history of telescopes: telescope is invented in 1608. by Lippershey, eyeglass maker, with further improvements by Galileo, Kepler, Huygens and Newton. There are two main kinds: refracting or Keplerian model (change direction when it enters at an angle) and reflective or Newtonian model (capable of reflecting light or other radiation). Refracting has one or more objective lens(es) in front and then tube with eyepiece for the focus at the end. Reflective has a mirror, usually even two, and an eyepiece for the focus at the end. In both cases eyepiece is convex lens which serves to collect refracted or reflected light.

(to be continued as soon as I find something about Webb`s optical power...)

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#### Pogo

Unfortunately, it doesn’t work that way. Whether the observer is using Keck, or a Newtonian beside Keck, or naked eye beside Keck, the photons still travel the same distance, therefore the timeline is the same. Webb will be about a million miles away at Sun/Earth L2. It may see the object a few seconds sooner, but to propagate the image live, the radio signal data transmission still travels that distance. Since Webb will record, store, transmit the data, it’ll be a delayed timeline. No, larger magnification does not reduce the time we are looking back because of light speed.

Helio

#### Captain Nemesis

Unfortunately, it doesn’t work that way. Whether the observer is using Keck, or a Newtonian beside Keck, or naked eye beside Keck, the photons still travel the same distance, therefore the timeline is the same. Webb will be about a million miles away at Sun/Earth L2. It may see the object a few seconds sooner, but to propagate the image live, the radio signal data transmission still travels that distance. Since Webb will record, store, transmit the data, it’ll be a delayed timeline. No, larger magnification does not reduce the time we are looking back because of light speed.
In that case, observational proof that alien civilization(s) do not exist, because we haven`t saw them yet with our telescopes, does not stand. Things are or aren`t regardless of us looking at them. Some people say, I even red articles they wrote, that we haven`t yet seen any e.t. in the Universe therefore they do no exist. How stupid conclusion. We haven`t seen them maybe because we are not able to see them. Tell me in 1400 years or more did they existed now.

I am pretty bothered with the question "do we magnify apparent image or actual image"? I am still searching for an explained answer. I am thinking about following experiment: we take an object far away, let`s say, 1/10 of the AU which means that the light will travel slightly less than 50 seconds to reach us. Both positions, observational point and object point, have precise atomic clock. We use telescope with 50x optical magnification and turn on continuos recording. At previously agreed exact time, object is manipulated in such a way to make it obviously different than moment ago. Atomic clock at the object`s point saves the accurate time when the objects was manipulated. We then chronologically compare if the recorded manipulation corresponds to the moment of the manipulation. If there is correspondence then we magnified actual image. If there is no correspondence, meaning that manipulation still occurs 50 seconds later regardless of our 50x optical zoom, than we only magnified apparent image.

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#### Helio

Why not make the clock display large enough to view directly with the telescope?

If the clock is placed 50 light-seconds from the scope, however, you can bet your house it will read 50 seconds slower. The speed of light is constant in every circumstance, ignoring gravitational gradients. Our units of length are now based on the speed of light rather than a stick in Paris.

#### Captain Nemesis

Why not make the clock display large enough to view directly with the telescope?

If the clock is placed 50 light-seconds from the scope, however, you can bet your house it will read 50 seconds slower. The speed of light is constant in every circumstance, ignoring gravitational gradients. Our units of length are now based on the speed of light rather than a stick in Paris.
Because the light from your clock display will travel same like the light from the object of the experiment reaching us subsequently. That is why we need to record and inspect the recording.

#### Atlan0101

The JWT looks in the IR. Its eyepiece isn't a singular eyepiece but a multitude of precisely matched pixelated-like eyepieces that when deployed will be an eyepiece with a total area as large as a good size house. The Hubble looks in the optical, not in the IR, and is much smaller in area of its eyepiece than the JWT is going to be (is supposed to be, providing everything works as it is supposed to work). Hubble is in low Earth orbit. The JWT will be much farther away from the interfering light of Earth in orbit of L2. Quite a huge difference in and for the scopes all the way around.

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#### Atlan0101

Why not make the clock display large enough to view directly with the telescope?

If the clock is placed 50 light-seconds from the scope, however, you can bet your house it will read 50 seconds slower. The speed of light is constant in every circumstance, ignoring gravitational gradients. Our units of length are now based on the speed of light rather than a stick in Paris.
I'm just noticing this particular post of yours, Helio. I would bet my house because of the particular word you used, "slower." "Slower" only applies to the act of separation of the clocks. Once precisely placed and absolutely fixed 50 light-seconds apart, the word 'behind' is the word that would apply . . . and each clock would read to the other, 50 seconds behind, constant. Each, in its own 4-dimensional bubble would read 50 seconds ahead of the other, but each would read precisely the same span of time between clock tics as long as they remained precisely 50 light seconds apart. The instant either one or both moves off the precise exactitude between them, all bets would be off.

If the movement between is a contraction of distance, each would read the other accelerating, speeding up, in clock tics (and light-wise, blue shifting). If the movement between is an expansion of distance, each would read the other decelerating, slowing down, in clock tics (and light-wise, red shifting (blue shift and red shift apply to two physics that are not necessarily always the same contextual physic, "distance" and "difference." Universe-wise, astronomers and physicists make the meaning flatly entirely 1-dimensional . . . and that isn't the reality, or the fact, of the matter : They make it entirely a separation between two points in space , , , when it can also, or alternatively, mean a lessening or growing separation in time, as observed from any distance away, between the observed and observable object (in the observable universe) and the unobserved and unobservable object (in the unobservable universe) -- the relative ghost (-) and the real object (t=0 point (+)). In 4-dimensional space-time, the geometry becomes an elastic multi-dimensional hyper-triangulation)).

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#### Helio

I'm just noticing this particular post of yours, Helio. I would bet my house because of the particular word you used, "slower." "Slower" only applies to the act of separation of the clocks. Once precisely placed and absolutely fixed 50 light-seconds apart, the word 'behind' is the word that would apply . . . and each clock would read to the other, 50 seconds behind, constant.
Agreed. "Slower" usually refers to rate, which woudl be misleading. Most people (public), however, would likely use "slower", but perhaps the lack of watch use will change this.

Atlan0101