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Traveling close to M42


gorann

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25 minutes ago, Stub Mandrel said:

What file extesnion does it take? It hasn't got one and it doesn't appear to be csv or similar.

Oops, should be a .xlsx ie Excel file. I'll repost if needed.

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32 minutes ago, Stub Mandrel said:

Still barfing on .xlsx :-) I have latest version of Office (O365).

 

Works for me.... Actually I use google drive on that PC so it's an export from that.

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3 hours ago, Stub Mandrel said:

What file extesnion does it take? It hasn't got one and it doesn't appear to be csv or similar.

It is a PDF.

Interesting, Stu. If I am reading the numbers correctly this means that there is no point where the object would have a greater surface brightness than it does at 13,000LY and would tail off quite dramatically as you started to get "close". Should I feel smug at this point? :lol:

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18 minutes ago, DRT said:

It is a PDF.

Interesting, Stu. If I am reading the numbers correctly this means that there is no point where the object would have a greater surface brightness than it does at 13,000LY and would tail off quite dramatically as you started to get "close". Should I feel smug at this point? :lol:

I'm afraid not Derek, the lower number means it's brighter....... ??

I'm by no means certain it's even correct, but it's perhaps a starting point to go from.

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1 hour ago, Stu said:

I'm afraid not Derek, the lower number means it's brighter....... ??

I'm by no means certain it's even correct, but it's perhaps a starting point to go from.

Oops!

It seems the only certainty in all of this is that my current lifestyle is not going to allow me to survive the 13,000LY journey to find out what the correct answer is :sad:

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6 minutes ago, DRT said:

Oops!

It seems the only certainty in all of this is that my current lifestyle is not going to allow me to survive the 13,000LY journey to find out what the correct answer is :sad:

Well the good news is that it's only 1359, not 13000. Any more optimistic?

Perhaps you could go into 'whisky induced suspended animation'...... ?

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1 minute ago, Stu said:

Well the good news is that it's only 1359, not 13000. Any more optimistic?

Perhaps you could go into 'whisky induced suspended animation'...... ?

That's a lot of whisky - but if I am required to take one for the team I will step up to the task :wink:

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2 minutes ago, DRT said:

That's a lot of whisky - but if I am required to take one for the team I will step up to the task :wink:

Given our inept fumblings at trying to work out the answer Derek, I reckon sending you might just be the only way to find out!!!

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Are you guys really giving up? We other stargazers need to know what M42 really looks like and we put our trust in you! Anyone know an expert that could tell us?

I just had a thought that complicates matters: if the interstellar nebulosity is in clumps that are shining by themselves (I think the Ha emitting stuff does), then these clumps would at some point in our travel there start to behave like point sources and increase in brightness by the square of the distance. Maybe we would be blinded by nebulosity........

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56 minutes ago, gorann said:

Are you guys really giving up? We other stargazers need to know what M42 really looks like and we put our trust in you! Anyone know an expert that could tell us?

I just had a thought that complicates matters: if the interstellar nebulosity is in clumps that are shining by themselves (I think the Ha emitting stuff does), then these clumps would at some point in our travel there start to behave like point sources and increase in brightness by the square of the distance. Maybe we would be blinded by nebulosity........

Hi gorann,

I think the consensus reached is that the brightness would not increase - except for the perceived brightness due to the larger angular diameter until we get close enough for the angles subtended get quite large - like say it is 24 light years away (the size of the nebula being near to that). We will then get some increase in surface brightness because the increase in angular diameter will be proportionally less than the decrease in distance. The descriptions we have from people who have observed the nebula with large telescopes under good conditions suggest it is likely we will  see some color. Following this, from the expert opinions in some of the links above, the probability is that as we get into the nebula, it is so diffuse that we will see nothing - exactly when I am not sure if even the experts can tell us. We would have to have a good idea of the 3D structure of the Nebula - is that even possible?

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17 minutes ago, beka said:

Hi gorann,

I think the consensus reached is that the brightness would not increase - except for the perceived brightness due to the larger angular diameter until we get close enough for the angles subtended get quite large - like say it is 24 light years away (the size of the nebula being near to that). We will then get some increase in surface brightness because the increase in angular diameter will be proportionally less than the decrease in distance. The descriptions we have from people who have observed the nebula with large telescopes under good conditions suggest it is likely we will  see some color. Following this, from the expert opinions in some of the links above, the probability is that as we get into the nebula, it is so diffuse that we will see nothing - exactly when I am not sure if even the experts can tell us. We would have to have a good idea of the 3D structure of the Nebula - is that even possible?

So, Beka, what about my comment above: What happens if the interstellar nebulosity is in clumps, which seems likely, that are shining by themselves (I think the Ha emitting stuff does), then these clumps would at some point in our travel to M42 start to behave like point sources and increase in brightness by the square of the distance, blinding us with nebulosity.

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The situation gets highly complex as you approach anyway. We have only considered M42 as a 2D object so far, obviously it is probably 20 or 30 light years front to back too, once you get to around this distance away, all the calculations get pretty messy!

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12 minutes ago, gorann said:

at some point in our travel to M42 start to behave like point sources and increase in brightness by the square of the distance, blinding us with nebulosity

A nebulous point source - that must be an oxymoron!

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and just think... there are many areas of M42 traveling at different speeds, huge shock waves and a few gas giant planets floating around in this star nursery. Point sources abound, diffuse nebula, reflection nebula, pillars of creation, planets...
 

M42 is not one object.... we just see it visually as one, with a few stars in it...

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11 hours ago, gorann said:

So, Beka, what about my comment above: What happens if the interstellar nebulosity is in clumps, which seems likely, that are shining by themselves (I think the Ha emitting stuff does), then these clumps would at some point in our travel to M42 start to behave like point sources and increase in brightness by the square of the distance, blinding us with nebulosity.

I think it hard to predict, as we get close it will all get brighter by the square of the distance but the clumps will increase in angular diameter so they will not be point like I imagine. Conceivably if if there is a denser region extended for a long distance in our line of sight we may see something.

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On 2016-02-10 at 17:04, Stu said:

Certainly not giving up, I'm working on something which I'll post when it makes sense.

I have some heavyweight reinforcements ie someone who knows what they are talking about, helping me out :) 

So Stu,

any conclusion from your heavyweight reinforcements yet

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On ‎06‎/‎02‎/‎2016 at 07:50, beka said:

I like the idea of removing the stars to give a sense of being closer to the nebula and comparing the two, I think it has been achieved to some degree. The image with all the stars looks flatter with no feeling of perspective - or is it just me???

Hi,

I would agree-I think that stars in front of nebulae look really great, but they can be more of a distraction, and, as you say, I think the image without stars somehow looks more 3d...:glasses9:

John

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11 hours ago, JohnSadlerAstro said:

Hi,

I would agree-I think that stars in front of nebulae look really great, but they can be more of a distraction, and, as you say, I think the image without stars somehow looks more 3d...:glasses9:

John

Thanks John, I agree.

Now we are just waiting for the final verdict about what it would really look like if we got closer....

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