APOD: EHT Resolves Central Jet from Black... (2021 Aug 04)

Comments and questions about the APOD on the main view screen.
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Chris Peterson
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Re: APOD: EHT Resolves Central Jet from Black... (2021 Aug 04)

Post by Chris Peterson » Thu Aug 05, 2021 2:33 pm

tomatoherd wrote: Thu Aug 05, 2021 2:09 pm overall a ridiculous collage. So the moon is between 250 and 300,000 light years in diameter? that's what in "Moon for scale" in that field implies. Why is it even there? none of the windows are in the range/order of moon measurement. Silly and wrong.
I couldn't disagree more. And I expect most APOD followers would disagree, as well. One of the most common things that people ask for in APOD images is something to give scale, and there is little better for that than the Moon, which everyone is familiar with. Seeing it (rather than a little line marked "0.5°") in the first image is very useful.
Chris

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MarkBour
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Re: APOD: EHT Resolves Central Jet from Black... (2021 Aug 04)

Post by MarkBour » Mon Aug 09, 2021 9:59 pm

Chris Peterson wrote: Thu Aug 05, 2021 2:33 pm
tomatoherd wrote: Thu Aug 05, 2021 2:09 pm overall a ridiculous collage. So the moon is between 250 and 300,000 light years in diameter? that's what in "Moon for scale" in that field implies. Why is it even there? none of the windows are in the range/order of moon measurement. Silly and wrong.
I couldn't disagree more. And I expect most APOD followers would disagree, as well. One of the most common things that people ask for in APOD images is something to give scale, and there is little better for that than the Moon, which everyone is familiar with. Seeing it (rather than a little line marked "0.5°") in the first image is very useful.
The Moon is shown in the initial image to give the viewer a sense of how large is the area of our sky occupied by the massive cloud shown there. The fact that a structure that is 11 million light years away would occupy that much area in the sky is somewhat mind-boggling to me. The image of our moon helps me to understand that.
Mark Goldfain