이 글은 아래 링크의 글의 reply입니다 (M82의 특이 구조에 대한)
http://www.nightflight.or.kr/xe/observation/32985

[M82 sketch]




[M82 description]




지난 관측시 해결을 보지 못했던 M82의 북서방향 edge의 희미한 성운기에 대해

Cloudy nights에 화두를 던졌습니다

원본 link
http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/3706568/page/0/view/collapsed/sb/5/o/all/fpart/1#Post3710650

그 반응이 재미있어서, 유의미한 comment들을 야간비행 게시판에도 한 번 소개해봅니다


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BillP
Loc: Vienna, VA

Wonderful detail you caught in that observation!

The two brighter spots and the arrow shaped V one can find in many photos ( example).
http://wind.caspercollege.edu/~marquard/astronomy/images/m82_moo.gif

However, the fan shaped extension I cannot find anyplace, sketch or photo. Interesting.

FYI, infrared photos do show material being ejected into the region you show though - link
http://2.bp.블로그spot.com/_DHtC4RLUPig/SwjYEYX2ADI/AAAAAAAAA2c/mG-NRFA9wuQ/s1600/M82Galaxy_ROW993171192.jpg

↑ 위 URL 중 블로그를 blog로 바꿔줘야 페이지가 열립니다. 교묘하게 금지 단어에 걸리더군요 ㅡ,ㅡㅋㅋㅋㅋ

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Hrundi
Loc: Estonia

Infrared photos show material being ejected into every region though.

Could it be an optical illusion though?

I noticed on some DSS photos that while the bright part of the galaxy narrows and bends "up" on the side with your fan,
the galaxy's general shape remains straight.

Thus would it be possible for the eye to perceive the bright part as a sort of straight 'guide line',
and thus extrapolate that the actually unbent part of the galaxy fans out in the direction opposite the bending.

Add in relatively minor glare from that bright star, and it could, I think, be enough to make it look as if there's an extension there.

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JayinUT
Loc: Utah

Nightwid,

Excellent sketch of M82, and terrific analysis.

Here are some images M82 Chandra , taken with the Chandra telescope.

They show the outflow of material from the galaxy in above and below the central region
but I don't see a flow out from where the broom you observed is.

Hrundi offers some good possible alternatives.

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NerfMonkey
Loc: NE Ohio

Excellent sketch.

I've seen the brighter areas within the galaxy that you mentioned as well as the dark lane in the center on several occasions.

But I've only noticed that faint fan-shaped area once, very recently.

To me it just looked like an extremely faint bit of fuzziness surrounding that end of the galaxy,
and I wasn't sure I was really seeing it or not.

Now I believe this structure is real but don't even have a guess as to what it could be.

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Jef De Wit
Loc: Hove, Belgium

Nightwid

I found one sketch out of 41 in Deepskylog (click link here) who may have the same mistery triangle.

The sketch was done by Guido Gubbels with a 25 cm dobson @ x178.



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JayKSC
Loc: Florida

Fantastic sketch, Nightwid!

It looks very much like a photograph, congrats.

As for the fan like nebulosity you've captured, it may be an optical illusion.

I find that when observing many dim, diffuse objects the hazy nebulosity (or galaxy glow)
nearer stars can seem to be a little brighter.

Just a guess.

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BillP
Loc: Vienna, VA

Just found another sketch that shows what you saw.

So others are seeing this also.

I also not that on many photos by amateurs there is significant nebulocisty in the rehion
between the core and that 1st bright star you have as teh reference point.

So definitely nebulocity in that region.

http://www.aaa.org/gallery3

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JayinUT
Loc: Utah

Nightwid,

I went back and looked at the Hubble image found here and with that bright star

as a reference it appears that the dust lanes or "shredded clouds" are bending down toward that star.

I wonder if that is what you and others are detecting?



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GlennLeDrew
Loc: Ottawa, Ontario, Canada

Very nice sketch!

My impression is that the 'bright' star contained within the nebulous extension is the culprit.

The light from this star could be scattered by one or more of the following:
- dirty optics.
- smudge on the eyepiece.
- dew on the optics.
- thin cloud.
- your own eye.

And the proximity of the galaxy and the star is a quite good candidate for the appearance of spurious extensions such as this.

The visual system has a powerful propensity for making such 'connections.'

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Jef De Wit
Loc: Hove, Belgium

Hi everybody

I still have a lot to learn about posting links, but I hope this will work better sketches of M82

http://www.deepskylog.be/index.php?indexAction=result_selected_observations&lco=C&title=Overzicht+geselecteerde+waarnemingen&seen=D&query=Zoek+waarnemingen&catalog=M&number=82&atlas=&atlasPageNumber=&con=&minDeclDegrees=&minDeclMinutes=&minDeclSeconds=&type=&maxDeclDegrees=&maxDeclMinutes=&maxDeclSeconds=&maxmag=&minRAhours=&minRAminutes=&minRAseconds=&minmag=&maxRAhours=&maxRAminutes=&maxRAseconds=&minsb=&minsize=&size_min_units=min&maxsb=&maxsize=&size_max_units=min&observer=&instrument=&minday=&minmonth=&minyear=&mindiameter=&mindiameterunits=inch&maxday=&maxmonth=&maxyear=&maxdiameter=&maxdiameterunits=inch&site=&minLatDegrees=&minLatMinutes=&minLatSeconds=&minlimmag=&maxLatDegrees=&maxLatMinutes=&maxLatSeconds=&maxlimmag=&minseeing=&maxseeing=&drawings=on&minvisibility=&description=&maxvisibility=&en=en&nl=nl&sort=objectname&sortdirection=asc&myLanguages=true&multiplepagenr=2

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TenthEnemy
Loc: Maryland

That's a nice sketch.

There actually is a fan shaped extension in that direction that is visible in the hubble picture.

I'd think it would be invisible the the human eye though.

You probably saw the contrast between the dark lane and the glowing sky around it,
along with the light from the nearby star, and assumed it to be a larger structure.

You can't always count on your brain accurately representing what your eyes are seeing.

I always "see" the complete bridge between M51 and NGC 5195, but I almost never actually see it.

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전체적인 의견은 'illusion이다'가 절반 정도, '나도 봤다' 또는 '누가 그린 스케치에도 그려져 있더라'가 나머지 반정도 됩니다

공교롭게도 그 성운기를 관측한 영역에 밝은 별이 존재하고 있어서 illusion이 맞는것도 같고

나도 성운기가 보이더라는 글을 보면 그러면 그렇지 하는 생각도 들고..
  
  
하지만 제 판단은 점점 illusion(착시)으로 모아지고 있습니다

아무리 관측을 잘 했다고 해도 사진에서 흔적도 없는 구조가 보일리는 없고,

더구나 찬드라 망원경으로 찍은 X선 사진으로도 관측되지 않은 구조를 봤다고 주장할 수는 없을 것 같습니다

(사실 X선 사진에 나온 구조를 가지고 육안 관측의 증거로 제시한다는 것이 더 웃긴 일이 되겠죠 ㅎㅎ)
  

사진과 안시에서 보이는 것이 많이 차이나는 대상 중에 하나로 M3을 꼽을 수 있습니다

M3의 dark lane이나 성단 내부의 star chain은 안시로는 잘 볼 수 있지만 사진에서는 노출 과다 문제로 거의 보기가 어렵습니다..

하지만 M82의 성운기는 아무것도 없는 맨땅(맨우주?) 위에 있는 분이기 때문에 M3의 case와는 좀 다릅니다





어쨋든, 다음 관측에서는 M82의 mystery triangle에 대해

재관측을 진행할 계획입니다  -최고의 시상이 갖추어진 날에 한해-

관심 있는 분이 같이 확인해 주시면 더 좋고요.. ㅎㅎ

안시관측의 재미는 이런 '감질나는 맛'인 것 같습니다   ^^;;
  



                    nightwid 我心如星