Don’t ever question the scientists because the science is settled. Top French scientist Etienne Klein tweeted a photo of a slice of chorizo and told his nearly 100,000 Twitter followers that it was a ‘space telescope image’ of the nearest star to the sun. Tens of thousands of people believed him without questioning anything. The…
@iamtanmay
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34d

Ok, he tweeted the next day that he wanted to troll people…

…let’s just accept it at face value, rather than a serious scientist actually trying to sell the public on something this moronic

For one, his rivals, other scientists would immediately trash him, so they could get ahead in their careers. Some people can be that stupid, but its a rare quality

Cold Hotman
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24d

It’s a piece of sausage. It’s clearly a joke.

@iamtanmay
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14d

I think so too. People are too sensitive

@iamtanmay
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24d

Wait, for real ? The nearest star is 4 light years away. IT TAKES LIGHT… 4 YEARS to reach it ! How in fuck’s name, did someone believe that we could just take a photo of its surface ?

Like all we can get is a point of light in the sky, a couple of pixels, that’s it. Its impossible to actually see what it looks like.

Cold Hotman
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24d

I don’t understand, we’re being pummeled with old light from the stars all the time. With optics that as theoretically good enough, we could point the scopes at any star and immidiately see the surface. In this example, exactly how it looked 4 years ago when the light left the star?

@iamtanmay
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24d

Oh, and hey. Welcome to Wolfballs. Lots of newcomers these days !

Cold Hotman
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24d

Thanks!

@iamtanmay
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24d

I am half knowledgeable of Optics, worked to set up some laser systems.

Since a star radiates in a sphere, at a distance of 4 light years, how many photons do you get ? I am assuming handful per second based on how they look twinkling at night. Human eye detects min. 2 photons. You need 10,000 per pixel. Let’s say we need 512x512 res, which would be blurry. That’s ~250,000 pixels or 2.5x10^8 photons. Exposing over time to collect more photons won’t work, since stars’ surfaces are dynamic, look at our sun.

We don’t even have good telescope images of Pluto, which is only 5 light hours away. We have to fly spacecraft close by to take decent images.

Cold Hotman
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24d

Fair enough, I wasn’t trying to comment on the details of the pictures but the premise that it takes 4 years for light to reach the nearest star, and that stops us from taking instant snapshots.

But you make some interesting comments;

Since a star radiates in a sphere, at a distance of 4 light years, how many photons do you get ? I am assuming handful per second based on how they look twinkling at night.

Are you sure? I did a bit of searching and this is presented as the equation for a star the size of our sun at 10 lightyears, which claims 1 million photons per square centimeter per second. That’s an awfully big difference from your assumptions.

You need 10,000 per pixel.

That’s a lot more than people are claiming on the net. While I haven’t been able to find accurate information (photons per sq/cm per second), the claims are the sensitivity is down to a single photon and the Webb operators have stated that the first photons have hit the sensors and they use it to calibrate.

Seeing that the Webb telescope is imaging in low-wavelength red and infrared, perhaps experiences from other situations isn’t comparable?

@iamtanmay
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14d

Yeah, I could be wrong. My Optics knowledge is only 50% and the rest I am filling in from my knowledge of general physics

  1. I did not use dimensions/units on surface/time sorry. I was thinking human retina size per sec. 1 million photons per s.cm2 is it ? Thanks for correcting.

  2. There are single photon detectors. But we want to rebuild an image, not just collect photons, right ? You would need to figure out which parts of the star, the photons come from to create the details. If I imagine the star radiating in a sphere, photons from different points would mostly ‘miss’ us, and we would be lucky to catch some which flew at the right angle. Mostly we would be getting photons that travelled in a straight line from the center of the star, rather than the other points, which would miss us.

Our sensor needs to calculate the angle from where the photon came on the sphere. That’s why we need bigger telescopes, big surface area increases chances of catching the photons from other angles.

  1. There’s effects of diffraction. The photons are not coherent laser light, but scattered waves. I am not sure what effects this has at this distance

But the biggest point is, our telescopes could not even make high resolution images of planets in solar system. We had to send probes to make those. I think that means there are serious Physics limits at work.

@squashkin
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14d

> puts out fake pics

> “plz continue to send us billions to do important research via involuntary taxation ok thx byeeee”

Post anything, all are welcome. No one can kick your post here. Do what you like. @WiggleHard bans nothing and exiles nobody (Dont doxx wolfballs users, no posting of porn/nudes or foot fetish material unless it involves political scandals, no ads for sex sites or dating sites; do that on your own time, no solicitation for pyramid scams, no posting job advertisements unless from official job sites, no posts supporting pedophilia, not all love is love) also: (we cannot allow violations of the patriot act concerning how we speak, no calls for violence, suggesting you are personally harming someone ect. These things are not free speech protected by law but actually against the law and could get the website shut down.) (no spam posting, especially spam posting of what could be considered symbols of hate) examples: guy posting nazi flag 5 times in one day, guy posting “whitey is the devil over and over, im going to use my best judgement on this one rule)

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