At the same time, I was kind of expecting something new and revolutionary. I don't see that here. I see "much better," but nothing really game changing. The pictures we're seeing look great, but twenty five years ago we were all oohing and awing over the HST pictures. This seems rather underwhelming to me.
It terms of resolution and ability to pick out distant objects out of the background noise, it blows HST out of the water, but this is the least interesting part of JWST. Hubble was a visible light and near-infrared telescope and so could only really do science on objects and features emitted at those wavelengths. Older objects however, have been red shifted so much that most of their light is in the mid and far-infrared, and that is where JWST excels which means that it can look at objects much older and closer to the big bang than HST ever could. Additionally, IR spectroscopy is very useful in determining molecular composition, as molecules have a very distinct IR emission spectrum related to their structure and how the molecules bend and vibrate:
https://www.savemyexams.co.uk/dp/chemistry_sl/ib/16/revision-notes/11-measurements--data-processes/11-1-spectroscopic-identification/11-1-4-infrared-spectroscopy/JWST has already managed to measure the molecular composition of the atmosphere of a planet 1000 light years away. That is remarkable.
https://www.esa.int/Science_Exploration/Space_Science/Webb/Webb_reveals_steamy_atmosphere_of_distant_planet_in_exquisite_detailAlso, HST was able to look back to about Boom+500 million years. JWST might be able to go back as far as Boom+100. Is that 400 million year difference likely to be all that meaningful?
Long story short: yes. The transition from the dark age to the first stars being born occurred somewhere in the period of 100-500 million years after the big bang. With JWST there is a good possibility of being able to observe the very first stars that ever existed, and how the large scale structure of the universe was created.
Lastly, I'd be interested in knowing how much of what we're seeing is data and how much is interpolation. The reason the current picture looks like a painting is because in some respects it is. If nothing else it was colorized. I'd be curious to know how close to the pretty pictures the raw data is. Or, more to the point, how much of that is human interpretation.
Vox did a pretty summary of how the photos are colourised.
https://www.youtube.com/watch?v=WSG0MnmUsEY&t=211sTo summarise: the telescope itself monochromatic, so the raw data is just going to be a black and white photo. To get any colour at all, you have to take several exposures with different filters that select specific wavelengths, and then combine them digitally (your digital camera is also monochromatic at the sensor level but uses an in built filter to create a colour image. If you can use broadband filters in the red, green and blue spectrum, you can can generate true to life pictures, and when Hubble or JWST takes pictures of things like Jupiter or planets in our solar system, this is what you see. For other objects, you instead use narrowband filters that select only a very specific wavelength that corresponds to a particular atomic feature (for example
H-alpha) and then map that to either the red green or blue channels in the picture. That way the composite photo becomes a map describing the composition of the thing you are looking at. It's not interpolation, any more than representing population density using a graph like
this is interpolation. It's just a method of data presentation. The data itself is real.
Topic: The Official Space and Astronomy Thread v. Well, this is weird. (Read 193630 times)