B How much in the past do we see these planets?

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The HR 8799 star is located 129 light-years away, and thermal emissions from its planets can be observed in infrared images. These emissions do indeed travel at the speed of light, meaning the observed infrared data reflects the planets' appearance from 129 years ago. Infrared radiation is a form of electromagnetic radiation, similar to visible light but with a longer wavelength. This confirms that the image captures a historical view of the planets. The discussion highlights the relationship between distance, light speed, and the observation of celestial bodies in different wavelengths.
Dreksler
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This infrared image shows planets that are orbiting a star called HR 8799, since these are thermal emissions does it still mean planets here that we see are 129 years in the past?
The HR 8799 star is 129 light-years away from us, in this image we can see thermal emissions coming from these planets. Do these emissions move at the speed of light? If so does it mean that what we are seeing in this image is how the planets looked like in infrared 129 years in the past?
 

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Infrared is electromagnetic radiation, just like visible light (it just has a different wavelength), so yes and yes.
 
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