Star-hopping is one of my favorite activities. Unlike star photography, it provides instant gratification and can be done alone or with a group. Observing the stars after dinner is really a nice way of concluding an evening with friends and family. And star-hopping does not require a large telescope. A small, easy-to-carry refractor will do the trick for most of the easy-to-find objects. Star-hopping to objects and looking at them through a telescope is also a good way of attracting kids to astronomy.

Star-hopping allows you to search out faint objects like galaxies or nebulae by starting from a bright star and hopping little by little towards your target. The main advantage of the method is that it does not require a precise alignment of the telescope mount. Many mounts are motorized, and when the ads claim that locating any object is done by computer... well, I never saw one that worked completely accurately. Asking a computer to find the Andromeda Galaxy and having your telescope point to the empty void of space is a fast way to get frustrated. So forget about motors and let's travel in the sky from star to star.

How it works:

Find a nice, dark-sky site away from trees or street lights. Set up your telescope. If your mount is equatorial, roughly turn its axis towards North, and tilt it an angle equal to your latitude. The compass of the iPhone and the latitude value displayed in Starmap's Location section are a valuable help. But don't stress over having an exact alignment. A rough alignment is quite enough. Before starting your star-hopping observation, activate the Path Finder option in the Settings. (Note: you should have purchased the PRO version ... thank you for that!)

Then, use Starmap to help you choose what you want to observe. The Tonight section in the catalogs will tell you what can be seen right now. Use the filters to select you mean of observation, your time (obviously now), and what kind of object you want to reach. Let's go for a small telescope, and look for galaxies. Starmap will provide a list of what you can observe.

We'll search for the Andromeda Galaxy. Scroll down until you find it in the list. Three stars means it's really worth looking at, 3.5 is the magnitude and the short description says it's easy to locate. That makes it a good starting point for beginners.

Select Andromeda, and touch the orange search arrow in the Coordinates section. Starmap will go back to the map. Follow the search arrow that guides you towards Messier 31, the Andromeda Galaxy. With the Path Finder option activated, Starmap will draw a green line from the galaxy to the closest bright star you can observe with the naked eye. Notice that the star Mirach is our starting point. Touch the star to select it.

Next, make a prolonged touch anywhere on the map to bring up a set of map tools. Tap the telescope icon to display the eyepiece view. (Of course, you will have already entered your optics configuration so that what you see in Starmap exactly reflects what you see in the eye piece.).

Now comes the fun part of star-hopping. Point your telescope at Mirach. It's a bright star and getting it in your eye piece should be quite easy. Compare what you see in reality to what Starmap displays on the screen. The trick of star-hopping is to identify a pattern of other stars around your target star. For instance, you might see four stars making a nice square, or an arc. Or, a bright star with three little ones around it. Be creative.

If you cannot find any matching pattern, the image could be inverted. This is the case for refractors or if you are using a diagonal mirror. Starmap needs to know that your telescope inverts the image. Use the upper right button to access your optics configuration. Select the suitable inversion.

Once you have Mirach well centered, follow the green line to reach M31. Always move your telescope by small amounts at first, without losing Mirach from the field of view. Once done, move the map on your device to reflect what you see for real. From move to move, you will soon reach the Andromeda Galaxy.

My advice is to use an ocular with the largest focal view. First, this provides more luminosity, and second, the broader the field of view, the easier the star hopping.

Once you master this easy star-hopping activity, you can apply the same principles to star-hop to other objects in the sky. Have fun and let me know how it works out for you!

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