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Although we have only been observing for 100 odd years in our time frame, the things we have observed have been over billions of years. Remember that distance
by gerdesj 5y ago
Although we have only been observing for 100 odd years in our time frame, the things we have observed have been over billions of years. Remember that distance is time! Think about what a light year means - it's the distance that light travels in one year.
The Milky Way (the Romans originally named it that - when you get a decent view of it with no light pollution, it does look like a milky road) is roughly 100,000 light years across. Andromeda is about 2.5 million LY away and so any light from it that we see is getting on a bit. Andromeda is counted as part of the "local group" so considered close to us. Really far away stuff is billions of light years away.
That new satellite that's all over the news - James Webb - is something else. Hubble was seriously impressive, even with its "squint" (technical hitch that needed correcting shortly after its launch). Hubble has delivered some of the most stunning science and imagery possible and JW will go much, much further.
Just you wait until James Webb starts delivering results. It will be awesome, and I don't use words like that lightly.