As my father, who grew up poor in rural Portugal during the depression, would say, "it's better to have it and not need it than to need it and not have it."Chris Peterson wrote:I scan my mouse over the links and check where they go before clicking. I can usually tell if it's something I want to follow.DavidLeodis wrote:One personal gripe (apart from the colours of the processed image) is that as I like to use links in the explanation to APODs I did find the 27 links in the explanation to this APOD were far too many, such that I gave up on using many of them. There has been a tendency for quite some time now to increase the number of links to further information (which must take time in the production of an APOD) but I wonder just how many ever get used?
In any case, it's easier not to click on a link than it is to follow a link not present. Better too many than too few.
APOD: M42: Inside the Orion Nebula (2014 Apr 08)
- Anthony Barreiro
- Turtles all the way down
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Re: APOD: M42: Inside the Orion Nebula (2014 Apr 08)
May all beings be happy, peaceful, and free.
Re: APOD: M42: Inside the Orion Nebula (2014 Apr 08)
From the description:
"Also known as M42, the Orion Nebula spans about 40 light years and is located in the same spiral arm of our Galaxy as the Sun."
The above sentence is missing the word 'currently' between "is" and "located". The orbital velocity of our solar system around the Milky Way is independent of anything (and everything) else in the galaxy, including the current arm we're sailing through. Look at extinction charts for Earth and you'll notice regular minor and major events. About every 65MY we drift through another busier part (i.e. "arm") of the galaxy, the last time was ~65MY ago.
"Also known as M42, the Orion Nebula spans about 40 light years and is located in the same spiral arm of our Galaxy as the Sun."
The above sentence is missing the word 'currently' between "is" and "located". The orbital velocity of our solar system around the Milky Way is independent of anything (and everything) else in the galaxy, including the current arm we're sailing through. Look at extinction charts for Earth and you'll notice regular minor and major events. About every 65MY we drift through another busier part (i.e. "arm") of the galaxy, the last time was ~65MY ago.
- geckzilla
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Re: APOD: M42: Inside the Orion Nebula (2014 Apr 08)
This sort of information is not known with enough certainty to be included in an APOD.JeffGee wrote:From the description:
"Also known as M42, the Orion Nebula spans about 40 light years and is located in the same spiral arm of our Galaxy as the Sun."
The above sentence is missing the word 'currently' between "is" and "located". The orbital velocity of our solar system around the Milky Way is independent of anything (and everything) else in the galaxy, including the current arm we're sailing through. Look at extinction charts for Earth and you'll notice regular minor and major events. About every 65MY we drift through another busier part (i.e. "arm") of the galaxy, the last time was ~65MY ago.
Just call me "geck" because "zilla" is like a last name.
- Chris Peterson
- Abominable Snowman
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Re: APOD: M42: Inside the Orion Nebula (2014 Apr 08)
Not really relevant, because regions like the Orion Nebula are very short lived. From its beginning to its end, there won't be a major shift in the relative position between us and it (especially as it's moving in a similar galactic orbit to us).JeffGee wrote:From the description:
"Also known as M42, the Orion Nebula spans about 40 light years and is located in the same spiral arm of our Galaxy as the Sun."
The above sentence is missing the word 'currently' between "is" and "located".
Independent in a sense. However, everything in our region of the galaxy is in a fairly similar orbit.The orbital velocity of our solar system around the Milky Way is independent of anything (and everything) else in the galaxy, including the current arm we're sailing through.
Theories based on this idea are poorly supported by evidence.Look at extinction charts for Earth and you'll notice regular minor and major events. About every 65MY we drift through another busier part (i.e. "arm") of the galaxy, the last time was ~65MY ago.
Chris
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Chris L Peterson
Cloudbait Observatory
https://www.cloudbait.com
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Chris L Peterson
Cloudbait Observatory
https://www.cloudbait.com