When starting in astronomy, we all have difficulty understanding how to use a Telescope to appreciate and enjoy the objects in the night sky.
Often, we do not even read the instructions of the instrument, and we want to watch straight away. Although it is highly advisable to read the instructions that come with it, we can help you to begin in the exciting field of astronomy.
One of the most common mistakes people make when trying to observe celestial objects using a new telescope is that we do the search using the lens or “eyepiece”, which is incorrect. We should use a “wide angle” lens such as a 32 mm or 35 mm, which covers more of the sky; these lenses have a field of view wider. If we are trying to find the moon with the telescope, with a lens of 32 mm (covering more area of the sky), you could see the full moon, so it is much easier to find with this lens.
If you use a medium eyepiece (e.g., 25 mm), it will be harder to find the moon since this covers less sky area. In some telescopes, using such a lens could see only part of the Moon. Therefore, the ideal is to look first with the 32mm lens, have it centralized, then we can test using other lenses, such as 25mm or 12mm for seeing lunar craters closer, as shown here:
Example: For use in Puerto Rico, adjust the frame, so the arrow is at number 18 (latitude 18 degrees):
To ensure good accuracy of the telescope, we must make sure that both the telescope and the Finder Scope are pointing to the same place. The “finder scope” is the tiny telescope used as an “aim” to help locate objects.
Although both appear to be pointing to the same place, it is imperative to make an adjustment on both (the telescope and the finder scope) and ensure that both are looking, with accurate precision, at the same place. To accomplish this, just choose a distant light pole and point the telescope towards it (to avoid confusing that light with the other posts, choose a post on its own).
Before you point the telescope, remember to lose the two screws that holds the telescope and then you can point it at a distant lamp post to test whether the telescope and the finder scope are pointing to the same place. Check on the main eyepiece if the telescope is APPROXIMATELY looking to the lamp post we choose, and retighten the screws, so the telescope never moves. Now, let’s look at the finder scope to see if it the lamp post is visible or not.
Slowly, using the two wheels or cables to move the telescope, locate the lamp post and make sure that the light is centralized in the eyepiece (looking through the lens 32mm). Then, without moving the telescope, slightly loosen the screws that holds the finder scope and look through it while adjusting those wheels to centralize the light pole in the finder scope too.
Once again look in both the eyepiece and in the finder scope to confirm that in both the lamp post is centralized. After having the finder scope and the telescope pointing exactly at the same place, it will make it much easier to find objects in the sky. Now, search for the Moon with the finder scope and you’ll notice that when looking through the eyepiece, the Moon will be there too.
Use the same technique to locate other objects such as planets as they are visible to the naked eye, such as Venus, Jupiter, and Saturn; they look like bright stars, but don’t “blink”.
As for the tripod, it is important for it to be leveled; by stretching the legs of it, be sure the ground is relatively flat or stretched more than one leg than others to compensate so that the top of the tripod is fairly level. Some tripods bring a bubble level integrated. If yours does not have one, buy a cheap level in stores like Home Depot, Walmart, etc.
Another adjustment to do with the telescope is to adjust the mount to the latitude where you are. For, e.g., if you are in Puerto Rico, adjust the mount to approx. 18 degrees. This only needs to be done once, and you can always leave at this latitude once the mount is fixed.
The next thing is to check whether the telescope requires the mount to be aligned. Telescopes with equatorial mounts must be aligned to the north to locate celestial objects and to “chase” according to the Earth’s rotation.
If you are looking at the moon, you’ll notice that it is gradually going out of the field of view; this is because our planet is rotating. If you have the telescopes properly aligned to the north, it will be easy to correct this; just turn the wheel to move the telescope sideways.
How do you know where north is and how to align north?
At dawn, the sun rises in the east, while the dark is in the west. If you extend your left arm to the area where the sun sets, and your right arm to the area where it rises, you are looking ahead to the North. Alternatively, you can simply use a compass.
Some models allow you to rotate the telescope mount to point north. If your telescope does not permit this, you can carefully lift the telescope and tripod and accommodate everything, so the mount is looking towards the north.
By setting the mount to the latitude of your area, and having the mount pointing north, you will notice that the telescope is approximately pointing to Polaris (the Pole Star). You can also confirm whether you are looking to Polaris or not, comparing the stars you see in your area of the sky with the stars that are supposed to be there according to the Stellarium planetarium software (free).
Using the Stellarium, you will see what astronomical objects are in the sky tonight and then locate them with your telescope.
After all these step, just enjoy your night
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