Observation of deep space objects includes observation of nebulae, galaxies, star clusters. If you have chosen these objects for telescope observation, you need to consider several conditions for successful research. Firstly, it is a perfectly clear and transparent sky (without dust, fog, clouds), and secondly, it is the absence of any illumination: it can be scattered light of night lamps, light of dawn or light of the moon.
How to watch the sky
The first thing a novice deep-sky observer should decide is where to observe. It should not be located near roads or railroads, within the city. Next, we will consider the weather conditions. The least favorable conditions for observations are cold, damp nights with fog, and also when there are clouds in the sky. The sky should be black and blue, the stars in the sky seem to be the brightest when viewed with the naked eye (plus, since even the weakest ones are visible, it seems that the sky is covered with stars). It is also worth paying attention to the wind: if there are moderate air currents, it will not prevent observations, but if the wind is very strong, in this case, there is a possibility that the weak stars will not be visible, as well as begin to distort the contours of the nebulae.
The geographical latitude of the observation site should also be noted. In this regard, the extent to which the highly observed object rises above the horizon is taken into account. The position of the object in the zenith (90°) is considered to be absolute (i.e. the best position for observation). If the height is less than 90°, the amount of light that reaches the observer decreases due to the increase in the length of the path of light in the atmosphere (the light is absorbed more strongly, the object seems less bright). For example, when the height of the object above the horizon is 30 є, the observer gets only 50% of the radiation from the object. If the object is located very low near the horizon, the observation of such an object, plus everything else, will make it difficult to solid haze or dawn light.
Proper preparation
So, it is necessary to plan everything carefully before direct observation. It is necessary to plan the exact time of observations (a particular day, time), as you must clearly understand the location of objects of interest to you in the starry sky during this period of time. Think about what you want to study in advance. When selecting objects and making a list, start with objects to the right of the central meridian, if you look south to have time to look at objects in the south-western part of the sky, before they have time to hide behind the horizon. Be sure to stock up on the search maps (make sure one is a survey map and the other is more detailed).
Before you start observing, we recommend you to sit with your eyes open in a dark room, so that your eyes can easily adapt to the darkness. Please note that the eyepiece may fog in cold weather and may also be subject to accidental breathing. To avoid this, wave your hand over the eyepiece lens periodically. Remember that alcohol and smoking can damage your eyesight at night (eat something sweet). Also, using a mobile phone or a regular flashlight to look at a card can ruin night vision (use only a red flashlight). You can observe the object as standing (with your hands behind your back) or sitting (with your hands in your knees). Do not forget to rest your eyes periodically, do a simple exercise (look left and right, down and up, help).
Nebula surveillance
In our latitudes, the best time for observation of nebulae is warm black nights in August-September. We recommend starting with simple objects that are easy to find in the starry sky.
This could be, for example, the Andromeda Nebula. The constellation of Andromeda can be observed at midnight in the eastern part of the sky, quite high above the horizon. In this constellation, on a clear, calm, moonless night, a weak fog spot can be seen with the naked eye - this is the Andromeda Nebula (M 31). The Andromeda Nebula is the most distant object of the Universe that can be seen with the naked eye (the light from the object reaches the Earth within 2 million years). It is necessary to note at once that at supervision of nebulae in usual amateur telescope it is not necessary to wait for something too surprising, most likely you will manage to see simply a foggy black-and-white stain with the central condensation. The matter is that the person in the conditions of insufficient illumination sees all only in black-and-white color (though in 300мм a telescope it is possible to discern some chromaticity at the Big nebula of Orion (М42))
However, not always the object of interest can be found in the sky with the naked eye. Therefore, you should always follow the following search algorithm: first, we use the star map to determine the search area, which includes not only the nebula itself, but also the nearby bright stars, and then try to find the same area in the sky. After that, you need to point the telescope at the object with the help of the viewer (moving from brighter stars to weaker ones).
If the foggy object of observation is weak enough in its brightness, it will be easier to find it in the starry sky "side vision", that is, it is necessary to look not directly at the object, and a little looking away (10 є in the direction of the nose). This is due to the fact that the retinal sticks, which are located on the sides of the central area, are more sensitive to light than the cones of the central part.
The development of the universe
When choosing a nebula, be guided by the possibilities of your technique. For example, in a telescope with a 60 mm lens you can see foggy objects of 10.5 stellar size, with a 100 mm lens - the nebula up to 12 stellar size, with a 200 mm lens of the nebula up to 13.4 stellar size.
What can be studied by observing nebulae in a telescope? First, it is worth mentioning at once that there are different types of nebulae. For example, if you observe a diffuse nebula (emitting light), it would be interesting to try to determine the angular size, shape (round, shreds, jets, sleeves, wrong), brightness distribution (darkening, ruptures, bright spots), presence of stars inside and outside the nebula. If the object for observation was a planetary nebula (formed by the upper expiring layers of stars' atmospheres), then here you can also pay attention to the angular size (usually compared with the angular size of Jupiter - 40 ''), shape (round, disk, disk with black holes, ring, oval, pear, scrap, etc.).e.), the brightness distribution, and to that end, try to determine the shade of color (blue, green, etc.), as well as evaluate the overall luster.