Comments by "H. de Jong" (@h.dejong2531) on "" video.

  1. No, it's not Photoshop. the actual images are in infrared. So we have to apply a transformation to make the image visible at all. For a color image, they take 3 images, using different filters (different wavelength bands, the same way a photo consists of R, G and B channels). After downloading, the imaging team assigns colors to each image and stacks them to make a color image. There is some artistic freedom in choosing which colors to use, but generally the longest wavelengths are mapped to red, medium to green and short to blue. for redshifted objects, the team can choose filters that match (more or less) the redshifted red, green and blue, so the image you get back out is an accurate representation of what the object would look like in visible light for a nearby observer.
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  2. No, that difference is negligible compared to the distance to the object.
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  3. We have millions of images of Earth. The Himawari and GOES images (and Meteosat, which uses a similar imaging system) provide images in 10k x 10k resolution, in 16 spectral bands. The spectral bands are optimized for meteorology, so you won't get an RGB image. They do have red and blue channels, not green IIRC. There are other Earth observation satellites in GEO: NASA's Terra satellite makes full-disk images. A little farther out at the L1 point, we have DSCOVR, with another excellent camera on board. https://www.youtube.com/watch?v=xPM2kITNtTs For more detailed images, we have lower-altitude satellites like Landsat, SPOT, the Maxar constellation etc. These are in low orbit, so they can't take full-hemisphere images. Still, several of these image the entire Earth on a regular basis. We have photos from several interplanetary missions, e.g. Voyager and Galileo, which made full-disk images on their way out. And of course the photos and film made by the Apollo missions.
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  4. No, it doesn't. Photoshop is not a camera.
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  5. That galaxy is closer than the rest, so we can see individual stars in it.
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  6. There's a refueling port. What we don't have yet is a spacecraft that can approach JWST without damaging the sunshield and without contaminating the mirrors with thruster exhaust.
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  7. Yes, we can do that, depending on the distance of the object (with a limited number of filters available, not all distances can be mapped exactly).
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  8. Diffraction is most visible for point sources of light. The light of a galaxy is smeared out, so its diffraction is smeared out as well.
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  9. Yes, micrometeorite impacts were taken into account when estimating the mission length.
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  10. That's incorrect. The images are postprocessed. They have to be, to make infrared images visible to the human eye. But they are not CGI. They are an accurate representation of what the telescope sees, just using different colors.
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  11. detector noise would make the image unusable at some point, but IDK how long that takes.
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  12. You're overlooking the 2 smaller horizontal spikes.
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  13. The Bible says very little about the stars, and does not contradict our findings.
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  14.  @charlesbrightman4237  you need to read up on spacetime and gravity. It doesn't work the way you think it does. The Moon orbits Earth. It doesn't fall into the 'dent' created by Earth: the speed of the Moon balances the gravitational force exerted by Earth. This happens on larger scales as well. The solar system isn't getting closer to the center of mass of our galaxy.
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  15.  @charlesbrightman4237  When misconceptions as big as "galaxies collapse in on themselves" are in play, explaining the basics has to take priority.
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  16.  @mattt6459  That's not how science missions work.
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  17. 6 seconds travel time, 3.5 Mbit/s data rate. There are downloads twice a day, so the images spend some time stored on the telescope before they're downloaded.
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  18. Astronomers have access to about 800 observatories all over the world, plus a dozen or so space telescopes. Nobody in his right mind will present fake images to a community that has so many ways to check your work.
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  19. These are photos, not CGI.
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  20. The upper limit would be the noise of the image sensor, I suspect. Hubble did some images with 12 days of exposure; JWST has less noise so it could go longer than that. But with 10 hours of exposure, JWST has already seen galaxies 13 bn lightyears away.
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  21. The gravitational lensing is essential: it allows us to examine faraway objects in more detail than would otherwise be possible. The images are very clear, clearer than they've ever been for an infrared telescope. Just because you don't like the image, doesn't make it fake or unclear, or not useful. Capturing the same area Hubble did was not luck, it was planned.
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  22. Computers are not used to sharpen these images. Colors have to be chosen: JWST observes in IR.
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  23. Science starts with observations. Scientists try to find an explanation for those observations, this becomes a model. The model is tested using more observations or experiments. When the model holds up and makes accurate predictions, it becomes a theory. The word 'theory' has a specific meaning here: it's not the colloquial opposite of 'practice'; a scientific theory is a model that has been shown to be accurate in a wide range of circumstances, and the best way we currently have to explain how things work. That whole process is called science.
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  24. No. JWST can look at objects 13 bn lightyears away. Moving the telescope 5 light-hours isn't going to make a difference.
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  25. Actual person. NASA director in the 1960s.
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  26. Astronomers have access to about 800 observatories all over the world, plus a dozen or so space telescopes. Nobody in his right mind will present fake images to a community that has so many ways to check your work.
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  27. That's correct. Color is added on the ground.
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  28. We have no way to repair Hubble at the moment. It's one failure away from ending its mission.
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  29.  @scottmanley  The RTGs would be pretty bright though, so it might show up as an unresolved dot.
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  30. That's nonsense. All of the originals are available via the Mikulski Archive for Space Telescopes.
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  31. no, they're not. They've shown Hubble and JWST images of the same area side by side, and there's a huge difference.
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  32. JWST will study life on other planets exactly as the documentary said: by detecting not only water but plant and pollution generated by other lifeforms. These things show up in the spectrum of an exoplanet's light, which JWST can measure.
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  33. The image can't be optically rotated. JWST uses reaction wheels, so it should be able to rotate without using fuel.
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  34. -5º to +40º.
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  35. Astronomers have access to about 800 observatories all over the world, plus a dozen or so space telescopes. Nobody in his right mind will present fake images to a community that has so many ways to check your work.
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  36. Yes. A very thin one, discovered by Voyager in 1977.
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  37. That's incorrect. Our sun doesn't have novas.
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  38.  @MrTurboTash  No. Because the dust is visible, we can estimate the total amount of dust in a galaxy. That number is too low to explain the gravitational effects we see.
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  39. It's a slight simplification, but still correct for most of the universe.
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  40. That's nonsense.
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  41.  @LevelEarth2021  Even one star falling on Earth would vaporize Earth completely, so this verse must be referring to something else. Keep in mind that meteors are called falling stars. We now know they are bits of rock, ranging from grains of sand to objects several km in diameter. Heliocentrism is not a belief. We have evidence: measurements of the position of the sun and the planets that irrefutably proves that the planets in our solar system, including Earth, orbit a common barycenter that mostly falls within the Sun.
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  42. you're missing the 2 smaller horizontal spikes.
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  43. Wrong, these are all photos. Astronomers have access to about 800 observatories all over the world, plus a dozen or so space telescopes. Nobody in his right mind will present fake images to a community that has so many ways to check your work.
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  44. That's not a fact.
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  45. We expect that the first galaxies mostly had giant stars which would burn out quickly (few million years).
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  46. No.
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  47. Bullshit. There's no money in one theory over another, and the project has not been set up in a way that allows for things to be kept a secret. All images and data are published.
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  48. False, these are photos, not artwork.
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  49.  @Wonderduck1  Yes, it probably won't last long. Depends on the size of the star of course.
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  50. They didn't fool you though. The only people trying to fool you are the moon landing deniers; they're charlatans trying to fleece people by writing books and videos filled with nonsense.
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  51.  @olasek7972  That's incorrect. One of the videos around the showcase images had an interview with the people who process the images. They assign the colors manually. There is a convention (the longest wavelength becomes red, medium becomes green, shortest becomes blue) but they have the freedom to deviate from that depending on the image (JWST has narrowband filters to show e.g. methane emissions, if you want to create an image to emphasize this you'd choose the colors differently).
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  52. JWST works in infrared. So the images are generally a representation of what we could see if we have IR vision, not what the object would look like in visible light. There is one exception: distant objects are redshifted. So the light that used to be at visible wavelengths has shifted to IR. We can shift this light back to visible and get a decent approximation of what the object looks like in visible wavelengths.
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  53. it's not one or the other. Galaxies are stable structures, with stars orbiting the common center of gravity.
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  54. Even though they no longer exist, we can still learn from them how the universe works.
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  55. You missed the comparison between Hubble and JWST, where the JWST image has hundreds of stars not visible in the Hubble image. And Hubble can't see at all at most of the wavelengths JWST work at.
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  56.  @mattt6459  That's nonsense. No scientist is getting rich from his work. Free energy is a fantasy. Wake up, the people telling you you're being lied to are lying themselves.
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  57.  @mattt6459  Tesla found a way to distribute energy wirelessly (and inefficiently). He didn't find a way to generate the power to drive that transmitter that wouldn't cost money. So he'd have a system that cost money to run, and no way to make users of that power pay for it. Tesla's idea was economically unviable.
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  58. The launch cost around $150M. It helps humanity by allowing us to learn more about the universe.
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  59. 1. We don't know beforehand where that will happen. 2. We don't have the tools yet to scan the entire sky for changes to catch a star being born. That will change in a few years. 3. Stellar formation is slow. In our galaxy, the chance that 1 star was born in the last 25 years is about 10%. 4. Stars are born in regions with lots of dust which obscures these new stars until the remaining dust is blown away by the light from the new star, which takes a long time. So it's statistically unlikely we could catch a star in the process of igniting.
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  60. There is no 'inner space'. Outer space is anything outside our atmosphere.
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  61.  @Bolsa1971  The edge of space is generally considered to be an altitude of 100 km. At that altitude, there's so little air, an aircraft would have to fly at orbital speed to stay up. All satellites are above that: they rely on there being no atmosphere: in order to orbit Earth, you have to fly at 28,000 km/h. Without drag from the atmosphere, you can use a rocket to accelerate to that speed once and then coast for years. Those clips saying we can't get past the atmosphere are incorrect.
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  62. JWST can tilt to +5º and -40º on its vertical axis. So its field of view is a cylinder with its axis along the Earth-L2 axis. In 6 months, that cylinder sweeps across the entire sky
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  63. For a color image, 3 images are made, using different filters (different wavelengths, the same way a photo consists of R, G and B channels). These images are grayscale. After downloading, the imaging team takes these 3 images, assigns colors to each image and stacks them to make a color image. There is some artistic freedom in choosing which colors to use, but generally the longest wavelengths are mapped to red, medium to green and short to blue.
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  64. With 1 week of science observations done, no. They did catch one galaxy that's 13.1 bn lightyears away, just doing the showcase images.
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  65. It takes a few seconds to read out an image. Moreover, these images have an exposure time measured in minutes or hours. But for JWST's science goals, video is not necessary.
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