Tag Archives: How far away is Orion Nebula ?

The Orion Nebula (Messier 42)

The view cuahgt in high Def via the Hubble telescope. Image Credit NASA http://hubblesite.org/newscenter/archive/releases/2006/01/image/a/format/large_web/
The view cuahgt in high Def via the Hubble telescope. Image Credit NASA http://hubblesite.org/newscenter/archive/releases/2006/01/image/a/format/large_web/

The Majestic Orion Nebula, so massive that you can see it with the unaided eye, even better views are done by Binoculars. I love testing out new methods or new equipment on this object. . .Why? Well it gives me the excuse to look at it again, and secondly . . .it’s big and easy to spot.

The Facts . ..

As Always I like to present the reader or visitor.. . .kinda the same thing a background on what they are looking at and how to do it themselves in their own back yard.

The Orion Nebula (Messier 42, M42, or NGC 1976) is a diffuse nebula situated in the Milky Way in Orion’s Belt. Diffuse nebula are clouds of interstellar matter, mostly gas and dust. If they are massive enough they can jump start star formation and can be star nurseries.  Some of the stars can excite the gas of the nebula due to the massiveness and high energy radiation and cause the hydrogen in the nebula to shine.  These are also known as emission nebula. If the stars are not hot enough the light is reflected by the dust and are seen as white or bluish and are called reflection nebula. Many emission nebula can also have the additional reflection nebula component. Diffuse emission nebulae are often called H II regions because they are mainly consisted of ionized hydrogen [1]

M42 is located at a distance of 1,344 ± 20 light years[2][3] and is the closest region of massive star formation to Earth. The M42 nebula is estimated to be 24 light years across. It has a mass of about 2000 times the mass of the Sun.

Color

How does it get it’s color? does it mean anything or is it just random luck? No the colors tell a lot about what it is made of. Studying an object’s spectral lines helps determine what things out of our reach are made of.

The red hue is a result of the Hα recombination line radiation at a wavelength of 656.3 nm. The blue-violet coloration is the reflected radiation from the massive O-class stars at the core of the nebula. See we are learning alot about what this thing is made of. . .It gets even better . . .

To cause the the green hue, it was determined that the green spectrum was caused by a low-probability electron transition in doubly ionized oxygen, a so-called “forbidden transition”. This radiation was all but impossible to reproduce in the laboratory because it depended on the quiescent and nearly collision-free environment found in deep space.[4]

Am I the only one getting excited about this?

From dust stars are born . . .

The Orion Nebula is an example of a stellar nursery where new stars are being born. Observations of the nebula have revealed approximately 700 stars in various stages of formation within the nebula.

If you have the opportunity to go see the presentation at the Kennedy Space Center on the Hubble telescope in 3d on their I-Max. . .I highly recommend it. I came out amazed and humbled after what they presented on this subject.  Recently observations with the Hubble Space Telescope have given scientists the major discovery of protoplanetary disks within the Orion Nebula, these disks are also known as proplyds.[5] HST has revealed more than 150 of these within the nebula, and they are systems in the earliest stages of solar system formation. When you see them for yourself. . .yo are seeing the formation of solar systems around a young star. . . then take that moment and think of our own solar system in the same stage, simply amazing. The high numbers of them have been used as evidence that the formation of star systems is fairly common in our universe.

Stars form when clumps of hydrogen and other gases in an H II region contract under their own gravity. When the  gas collapses, the center material is pressed under gravity and the gas heats to extreme temperatures by converting gravitational potential energy to thermal energy. If the temperature reaches a high enough point, nuclear fusion will ignite and form a protostar, I would honestly love to witness this exact moment. The protostar is said to be ‘born’ when it begins to emit enough radiative energy to balance out its gravity and halt gravitational collapse. From this point on the star starts a struggle within itself to keep the force of gravity squeezing it on itself to balance withe force of energy emitted to keep the pressure pushed outwards.

Stellar wind and effects

On an object this big and massive. . .how can stars that it create affect the very “mother” that birthed them? Stars emit charged particles called a Stellar wind.  Young stars and massive stars produce stronger stellar winds. Much stronger than our sun.[6]

The stellar wind isn’t like “wind” that you are familiar with on a nice day at the beach, instead this is fast, hot and massive, so strong it forms shock waves or hydrodynamical instabilities when it hits the gas in the nebula. This collision cuases the gas clouds to have different shapes, much like a cloud in the sky. Don’t fret, this also pushes other gas into other clumps of gases and helps accelerate star formation by creating density inhomogeneities that lead to gravitational collapse of the cloud.

There are three different kinds of shocks in the Orion Nebula. Many are featured in Herbig–Haro objects:[7]

  • Bow shocks are stationary and are formed when two particle streams collide with each other. They are present near the hottest stars in the nebula where the stellar wind speed is estimated to be thousands of kilometers per second and in the outer parts of the nebula where the speeds are tens of kilometers per second. Bow shocks can also form at the front end of stellar jets when the jet hits interstellar particles.
  • Jet-driven shocks are formed from jets of material sprouting off newborn T Tauri stars. These narrow streams are traveling at hundreds of kilometers per second, and become shocks when they encounter relatively stationary gases.
  • Warped shocks appear bow-like to an observer. They are produced when a jet-driven shock encounters gas moving in a cross-current.
  • The interaction of the stellar wind with the surrounding cloud also forms “waves” which are believed to be due to the hydrodynamical Kelvin-Helmholtz instability.[8]

The dynamic gas motions in M42 are complex, but are trending out through the opening in the bay and toward the Earth.[9] The large neutral area behind the ionized region is currently contracting under its own gravity.

There are also supersonic “bullets” of gas piercing the hydrogen clouds of the Orion Nebula. Each bullet is ten times the diameter of Pluto’s orbit and tipped with iron atoms glowing bright blue. They were probably formed one thousand years ago from an unknown violent event.[10]

Photographing

Now the fun part, I know you all wanted to dive right in and skipped to right here. . .don’t deny it. . I was watching you.  So can you take good pictures of this yourself? Yes absolutely. It’s one thing to see a Hubble image. . like at the top of the page . . . see that I baited you with it. . no really I prefer you see what I am talking about and use it as a comparison to your own images. Do you need a fist full of expensive equipment? Depends on who you ask.

As a bit of background here I have met a wonderful bunch of astrophotographers who love the hobby and they can make some amazing pictures. However, every time I ask a question they tell me it can’t be done or they don’t think so. . but if you go buy some expensive things that they bought you can do just as good. I say no, don’t break the bank on something you have no idea if you are going to keep at it or continue to have an interest in it, you are going to run into many frustrating nights, sometimes I just want to throw the whole rig in the street. . . but no, there is a saying

“The harder the conflict, the more glorious the triumph. What we obtain too cheap, we esteem too lightly; it is dearness only that gives everything its value. I love the man that can smile in trouble, that can gather strength from distress and grow.”

Thomas Paine

Now my view on this is this, you don’t buy your child a Porsche for their first car, no you buy something that can take some lumps and bangs. . . I like the Celestron 6se. Honestly the guys who buy the 8SE spend a few hundred more, and yes it is better. but as someone who has never bought a scope before and didn’t know what to buy I will still recommend to someone who started like I did, the same thing I bought for the same reasons. honestly thought  . . .the guys waving their 8SE in your face  . . . it gets old. If I can do what I can on a 6 inch scope, you should be amazing with that 8 inch. . I know I would be.
So I had recently decided to take the photography to the next bar. I could not handle the drifting of the scope while taking pictures. I would fight to keep her on the target more than a sailboat in rough waters some nights. I bought a guide scope set up. After this, i will write up a guide on how to make it work with your 6se and an alt-az mount. . . much like I was told over and over that “it will never work. . . .”
My Celestron 6se with Orion 50 MM guide scope
My Celestron 6se with Orion 50 MM guide scope

So lets review the equipment: Celestron 6se, Orion StarShoot G3 Deep Space Color Imaging Camera, Orion Magnificent Mini Deluxe AutoGuider Package, and a home made wedge.I want to make a note for anyone who has never read anything I wrote before. I am not advertising nor am I getting paid for any sales from links. I do it because I honestly hated when I was looking things up and had to hunt for the stuff they were talking about. Lets see this wedge they said would never work:

Home made wedge of 3/4inch steel and an industrial door hinge. . .
Home made wedge of 3/4inch steel and an industrial door hinge. . .

Once you get things going and get the scope guiding, you are ready to take images. I want to break here and talk about guided verses unguided. can you take pics unguided? Yes, absolutely. I have up to now. I have had great results, but know your limitations. The Limitations are exposure times and a lot of bad frames due to tracking issues. The scope mounts just simply cannot keep up, even expensive ones will streak. thus enter in guide scopes. You can take unguided images while using the video method. Recording say an object with a video style camera and then using Registax to make a shot out of the frames by stacking them. Long exposure photos, which are required for diffuse nebula images, will more than likely have fits when you try this. Longest shot I ever got was 32 seconds with out streaking unguided. . .those were flukes. Once you guide. . you will never go back.  . . trust me on this.

One last bit I used to get this image is the Orion 0.5x Focal Reducer. This gave me a wider field of view but a smaller image. Sometimes it’s better to get the image in the shot than it is to get a closer shot. Astrophotography is 50% getting the images and the other 50% is the post processing, I am still learning how to do this and there are different techniques on different objects. . .I have been taking time off from writing to get images when I can, figure out the new gear and honestly trying to figure out how I want to tackle that part. I feel if I do it right it will help a lot of people struggling, so hang on with me. . .I will teach you.

So unguided I took this image a long time ago. I will add my old ones in so you can compare methods, I am not ashamed of my old pictures, it was a learning process. I feel if I show you where I was and where I am now, not only do my new images look better, but it will encourage those who are stuck or some one else can see it and say hey that’s what I got too, I’m on the right path.

be easy on me . . .my first attempt ever on M42
be easy on me . . .my first attempt ever on M42

so this was my first attempt over a year ago. It was cold as hell outside and I gave it a go. I felt it wasn’t bad. I wanted something to work with, the equivalent of this feat is to take a photograph of a few LED lights in a smoky room and trying to get the lights and the structure of the cloud. . . . I worked on my processing at this point.

take two, a few days later I tried again with a different camera and got this
Take two, a few days later I tried again with a different camera and got this

A bit better, I used the Orion StarShoot Deep Space Video Camera II and got this. . .I thought I was getting better. It’s not bad if you were doing a live feed withe camera you could use this a live feed I think. . . I captured a bit more than the first go around. then I took another crack at it in the high desert of Nevada, on a very cold night. . .how cold?

How cold is it? This cold . . .
How cold is it? This cold . . .

yeah it was so cold I had to stop after a while because not only did my scope start having troubles when it got so cold, but i found out I-phones stop working in extreme cold. . .I kept on until the optics started frosting over. I did get this image that night:

Orion nebula on 1-4-2014. I was rather proud of what I had achieved in almost a year of learning the hobby.
Orion nebula on 1-4-2014. I was rather proud of what I had achieved in almost a year of learning the hobby.

I was rather happy with this, the processing gave it a weird orange glow, something I liked about it. I see I was getting better.  All of these were taken unguided. This last one here was taken not with he video camera, but with the Orion StarShoot G3 Deep Space Color Imaging Camera. I learned that night the strength of the camera with the shutter I could keep open, I saw it had strengths to get the faint things.

Now Guiding the scope. If you get to this point in the hobby. . buy it. I like the piece I got because it has a focuser. It’s one solid piece and the 50mm does well with the 6SE. Orion support spent a lot of time with me and I will keep goign back to them for this very same reason. Even after I bought it I had some issues with software, but they were there for me when I needed them. With this guide I was able to leave the shutter open with no streaks as long as I wanted. I have a shot I left it open for 320 seconds. . . I as gonna go for more, but the dew started being a pain. .  so with out further ado

Orion nebula M42 taken on 1-21-2015
Orion nebula M42 taken on 1-21-2015

Unfortunately, the blog poster here doesn’t let me use TIF files, so you can see a better version on my flickr here. Tif files are larger and have better detail, 16bit vers 8bit Jpeg.  With that compression you lose detail. I was working on a Hydrogen-alpha (Hα) shot, I was having a little blending issues, and really wanted to get this image out to you all. the HA shot I have is not that bad it has a rough spot where you can see the blending of the different exposure times is a bit rough. .I’ll smooth it out and add it later.

Orion nebula in H-alpha (Hα) Yes I have to retouch this up and smooth the blending. it's delicate.
Orion nebula in H-alpha (Hα) Yes I have to retouch this up and smooth the blending. it’s delicate.

Here you are seeing the  H-alpha (Hα) illuminated. I will replace this image later  . . . .nah I will save a space for it and add the fixed version at the end. Also on the Flickr here

As always keep looking up,there is some of the weirdest most magnificent things you can ever image out there and its virtually free to see. . .you just have to look!

Data:

From Simbad[11]

Basic data :
M 42 — HII (ionized) region
Other object types: C?* () , Rad (3C,4C,CTA,Mills,MSH,NRL,PKS,[DGW65],[PT56],[WCO2009]) , X (XSS) , Cl* ([KPS2012]) , HII (LBN)
ICRS coord. (ep=J2000) : 05 35 17.3 -05 23 28 ( ~ ) [ 7500 7500 90 ] D 1981MNRAS.194..693L
FK5 coord. (ep=J2000 eq=2000) : 05 35 17.3 -05 23 28 ( ~ ) [ 7500 7500 90 ] D 1981MNRAS.194..693L
FK4 coord. (ep=B1950 eq=1950) : 05 32 49.8 -05 25 21 ( ~ ) [ 7500 7500 90 ] D 1981MNRAS.194..693L
Gal coord. (ep=J2000) : 209.0137 -19.3816 ( ~ ) [ 7500 7500 90 ] D 1981MNRAS.194..693L
Proper motions mas/yr [error ellipse]: 1.67 -0.30 [0.49 0.49 1] D 2009MNRAS.399.2146W
Radial velocity / Redshift / cz : V(km/s) 28.9 [2.7] / z(~) 0.000096 [0.000009] / cz 28.90 [2.70]   (~) D 2009MNRAS.399.2146W
Angular size (arcmin): 5.5 5.5 90 (~) (Rad) D 2006ApJ...653.1226Q
Fluxes (1) :
V 5 [~] E ~
Observation data: J2000 epoch
Subtype Reflection/Emission
Right ascension 05h 35m 17.3s
Declination −05° 23′ 28″
Distance 1,344±20 ly (412 pc) ly
Apparent magnitude (V) +4.0
Apparent dimensions (V) 65×60 arcmins
Constellation Orion
Physical characteristics
Radius 12 ly[a] ly
Absolute magnitude (V)
Notable features Trapezium cluster
Designations NGC 1976, M42,
LBN 974, Sharpless 281

References:

  1. “The Messier Catalog: Diffuse Nebulae”. SEDS. Archived from the original on 1996-12-25. Retrieved 2007-06-12.
  2. Reid, M. J. et al. (2009). “Trigonometric Parallaxes of Massive Star Forming Regions: VI. Galactic Structure, Fundamental Parameters and Non-Circular Motions”. Astrophysical Journal 700: 137. arXiv:0902.3913. Bibcode:2009ApJ…700..137R. doi:10.1088/0004-637X/700/1/137.
  3. Hirota, Tomoya et al. (2007). “Distance to Orion KL Measured with VERA”. Publications of the Astronomical Society of Japan 59 (5): 897–903. arXiv:0705.3792. Bibcode:2007PASJ…59..897H. doi:10.1093/pasj/59.5.897.
  4. Bowen, Ira Sprague (1927). “The Origin of the Nebulium Spectrum”. Nature 120 (3022): 473. Bibcode:1927Natur.120..473B. doi:10.1038/120473a0.
  5. McCaughrean, Mark J.; O’dell, C. Robert. (1996). “Direct Imaging of Circumstellar Disks in the Orion Nebula”. Astronomical Journal 111: 1977. Bibcode:1996AJ….111.1977M. doi:10.1086/117934.
  6. Ker Than, 11 January 2006, “The Splendor of Orion: A Star Factory Unveiled“, Space.com
  7. Mapping Orion’s Winds“, January 16, 2006, Vanderbilt News Service
  8. Denise Chow. Young stars blamed for space cloud ripples, MSNBC.com
  9. Balick, B.; Gammon, R. H.; Hjellming, R. M. (1974). “The structure of the Orion nebula”. Publications of the Astronomical Society of the Pacific 86: 616. Bibcode:1974PASP…86..616B. doi:10.1086/129654.
  10. “Gemini’s Laser Vision Reveals Striking New Details in Orion Nebula”. Gemini Observatory. 2007-03-22. Retrieved 2010-06-01.
  11. SIMBAD Astronomical Database”. Results for NGC 7538. Retrieved 1-24-2015.  http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=m+42&submit=SIMBAD+search