Viewing a single comment thread. View all comments

Astrofishisist t1_j1qgx2d wrote

Reply to comment by wowsosquare in A group of galaxies called "Stephan's Quintet" was featured in the opening scene of the Christmas movie "It's A Wonderful Life" (1946), where angels were speaking from. Left is from the movie, right is from the James Webb Space Telescope. by Yoprobro13

I wouldn’t call them fake, but you’re right in saying that we wouldn’t see them in the same way. It’s not that they’re not visible, but they just look different to us as we see optical light.

For a quick example you can look at a comparison between JWST and Hubble of these galaxies. The Hubble image is FAR closer to what we’d see with our eyes as it’s coloured according to the optical light that’s received. JWST has more false colour as it’s assigning different parts of the IR spectrum their own colours, but you can still see they look almost the same, it’s just that some parts of the image (the dusty bits in the Hubble optical pic) are almost transparent in JWST’s IR.

Even in optical though there’s some inaccuracy. For some telescopes the colour comes from ‘filters’ which tend to single out certain elements and assign them a colour. This isn’t always accurate to real life, but it just adds to the flair of a lot of images.

I 100% would not call them fake though. Infrared light is just as valid as optical light, it’s just that our own eyes can’t detect it. There’s no ‘fake CGI’ involved it’s just that the telescope is capable of seeing more light than our own eyes are capable of.

Just to reiterate infrared light isn’t just looking at how ‘hot’ these space objects are, it is actually the same exact type of light that we can see, just a different amount of energy. It’s like how dogs can hear higher pitched noises than humans can hear; it’s still sound, but our ears aren’t able to pick it up.

12

wowsosquare t1_j1qmb7q wrote

YOU are the best thanks for the perfect explanation!

I'd like to ask another question in the form of an ill informed statement

>infrared light isn’t just looking at how ‘hot’ these space objects are

Isn't it though? I mean I suppose an we could say that in the visible spectrum, we are looking at how bright things are (amplitude), but also what color they are...so in the IR we are looking at how hot things are (amplitude/ brightness), but also which frequency (color) they are emitting. And so the false color added by computer processing is assigned based on something like higher frequency IR = closer to blue, and lower frequency IR= closer to red?

1

Harbulary-Batteries t1_j1qw375 wrote

Heat is not the same as infrared light - heat can be emitted along a wide variety of wavelengths. We’re just looking at wavelengths and amplitudes on a different part of the spectrum.

3

kvetcha-rdt t1_j1roiko wrote

this is basically it. these telescopes are 'seeing' in wavelengths the human eye cannot detect - these images are basically just 'frequency adjusted' for our vision. It's a bit like night-vision goggles.

2