April 16, 2019



How to Observe the Orion Nebula With a Telescope


You can see the clusters of the “sword” of Orion, which, in combination with the nebulae, and we’ll talk about them later, will look good in any binoculars or telescope.

You can pay attention to the stars forming the constellations, and Orionids – the radiant of the meteor shower, which is usually observed from November to the beginning – mid-December. Please note that under Orion you can see the constellation Hare, about which we have a separate article.

Essential equipment

So, where to start dating Orion? Probably, it should be said that at least half of the objects that will be discussed are a rather small 70-80 mm telescope. However, for a deeper acquaintance, it is worth armed with a larger tool.

More info: https://astrobackyard.com/orion-nebula/

1) Great Orion Nebula. M42 and NGC 1977 (Running Man)

The Orion Great Nebula is a masterpiece left by the birth and evolution of stars in Cosmos. It is best to observe it in the sky, where it is visible to the naked eye (although even in the city you can see the central part of the telescope), since it is in the case of a dark sky that you will see magnificence, like a photo on the right, only without colors. Although there are reports of observers about the visibility of various shades.

Personally, I saw yellow shades in the center of the nebula in 16 “and 12” telescopes, and when the sky is lit, the nebula seems greenish, which, in my opinion, is an artifact, but rather interesting effect.

Observe the Orion Nebula is many-sided, it is an object for a separate study. A little note. Describing the details of this and other objects, we will mean that we are talking about the sky, suitable for the study of objects in deep space, that is, at least about the dark yellow-green observation zone.

So, if you have a small 60-80mm refractor at your disposal, first use a viewing eyepiece with magnification up to 50 times and a good field of view. In the complex, you will see the bright center of the M42 nebula, the trapezoid stars in the center may not be separated, but the overall impression will be worthwhile. Move the pipe across the “wings of the nebula,” from below there will be good views of the clusters of the “Sword” of Orion.

When lighting and to increase the contrast, use filters. On small telescopes, UHC-S, CLS or UHC filters are suitable, especially in the presence of light. Filters highlight dark and light areas, increase image contrast.

Having 114mm in the arsenal, and a better 130mm telescope, you can lift up to 100 times without such a serious loss of brightness, where you can see cloudy twists around the center and near the wings. On the ideal sky, the periphery of the nebula is well manifested.

However, always when observing the M42, do not buy into its deceptive brightness – aspire to a dark sky, where it will reveal even more details.

When the legendary hunter Orion became so proud that he began to strike anyone and began to pursue the Pleiades, the goddess Gaia sent a scorpion who killed him, and Zeus placed him in the sky, where he continues to “walk” behind the Pleiades in the daily rotation of the sky.

But let’s leave the ancient legends, and move on to practice. Few people noticed in the sky or at least did not hear about the constellation of Orion. The most beautiful figure of stars, bright enough to be visible even from cities, attracts the attention of even people far from astronomy.

Bright stars Betelgeuse, Bellatrix, Riegel have different luminosity and color, which in combination with the belt of Orion gives a special charm to this constellation. Indeed, unlike some Giraffe, which is very difficult to associate with an animal that gave it a name, in Orion an ancient hunter is easily guessed.


Running man and M42

The 150mm-200mm telescope gives a little more room for the applicability of filters; it is worth trying the OIII filter, which very seriously increases the detail of the oxygen component of the nebula. In general, in a 6-8 “telescope, the view of this object is so impressive that a trained person can be shocked. At the same time, it is better to first look at some dim display object so that the vision can be adapted to maximum sensitivity.

The companion BTO is the NGC 1977 nebula, which is also very interesting, above all, by a different response to light filters than its famous neighbor.

A separate conversation on the observation of the M42 opens for the owners of 10 “and large apertures. In addition to the absolutely incredible detail, which literally repeats the photos, color shades appear and, more importantly, there is a real opportunity to apply a somewhat non-standard filter for the M42 – H-Beta. With it go off many details of the nebula, however, the attentive observer will see that new ones appear, thus, to some extent, alternating the OIII and H-beta filters, we see a different object.

M78 and NGC 2071

These two objects are tough nuts for small telescopes. And yet, when searching for them on large apertures, you always notice a slight heterogeneity in … Seeker 50mm. In short, starting from the green observation zone, the M78 is precisely accessible to small (up to 90mm) telescopes in the form of a small cloud.

The interest in observing it is because it has a slightly different nature – it is a reflection nebula, that is, it mainly shines at the expense of stars that illuminate gas and dust, and not due to the glow and ionization of gas, as in ordinary emission nebulae.

Do not apply filters for M78, and generally for reflective nebulae. They, like galaxies, are very afraid of the bad sky and the transparency of the atmosphere, and under good conditions, they become very interesting. I advise you to use a telescope for detailed study of the M78 10 “-12”, although the owners of large apertures 14-16 “will undoubtedly reveal additional details, it is in 10” -12 “devices that the main aspects of this object are usually visible.


NGC 2022

Let’s turn our attention to another class of objects – planetary nebulae. Yes, Orion “hides into itself” a rather interesting similarity to the famous “Ring” M57. True, this nebula has a low stellar magnitude (different sources range from 11.6 to 14+ m), but in reality, due to its small size and sufficient surface brightness, it is available for observations at 8 “and more telescopes.

It responds well to OIII and UHC filter, this nebula resembles a ring of smoke in its shape. The object is also interesting because in 10 “I have often seen a greenish tint in it on increasing to 100x when the nebula is only slightly larger than the stars. Consider its small angular size when searching. I usually start with the stars of Orion’s “head” and move along the constellation in the direction of foggy, looking into the viewing eyepiece.

In an approximate area, it is useful to “blink,” introducing – taking out the filter between the eye and the eyepiece. The nebula is very noticeable “jumping out” against the background of nearby stars. Many people asked me if it was realistic to see this planetary in a 6 “telescope. The answer is simple – really, in the blue zone, my 150 / 2270mm Cassegrain Alter M615 coped with it.

More cool pics: https://apod.nasa.gov/apod/archivepix.html

NGC 2194 and the other two scatters

A good, quite interesting star cluster in the “baton” of Orion. It will require a 100 mm telescope in order to interest the observer, although it is also available in a smaller aperture. I also recommend the NGC 2169 cluster – it is even brighter (you can see it well in a 90mm refractor), which is interesting, the stars in it (in a 6 “telescope) form a clear number 37 (although this may be just an illusion).

Look and tell about your impressions of this object. Generally, I’m not a big fan of open clusters, however, for owners of 6 “and more tools, which, at the same time, have a decent field of view, I recommend trying NGC 2112 – it is much less concentrated.