I admit to being a confirmed star hop observer, preferring to start my night's session at a bright star or object, and travelling ever onward from there. However, my newest telescope came with a very seductive little feature, and I do find it useful from time to time. "Go To" telescopes are the rage now, with remote control location of objects. Enter M 66 into the keypad and within a few moments you will be looking at a very fine galaxy, having expended little or no effort to get there. "Push To" scopes work in a similar fashion, except you have to physically move the scope yourself, using arrows and numbers on the key pad to zoom in on the desired object.
If I want to visit M 66 using the Push To, here is what I must do. First, I must align my scope with two bright stars, after turning on the keypad and pointing my scope to vertical position. Lately I have been using Regulus as my first star and Polaris as my second. I recently switched to Arcturus as my first star. This is done only once per night. Then I select "M" object on the keypad, punch in 66, then "Enter", and I am off. The key pad tells me how far to move the scope in r.a., and then in declination. Within seconds, I have located M 66. It is much faster than a Go To, since I can move the scope at any desired speed I wish, and the key pad runs smoothly on a single 9-volt battery. So I sometimes use this handy feature to get to my starting object. But what else can it be used for?
No doubt from a really dark sky, it can be used to locate objects much fainter than M 66. The entire NGC and IC catalogue are programmed into the computer, as well as nearly 7000 stars. From suburban skies, however, this is not a big advantage over star hopping. However, there is a feature I like, called "Sky Tour." Each month has a set program of 12 showpiece objects. Last night I entered "May" into the tour feature, and was treated to an amazing group of galaxies (mostly, as it is the season), a globular, a planetary nebula, and a double star. In case you are interested, here is the list of objects in the Orion May Sky Tour.
1) M68--eg 4590 (too low from my site--blocked by trees)
2) M104--Sombrero Galaxy
3) M60--eg 4649 (twin galaxies!)
4) M84--eg4374
5) M99--eg 4254
6) M64--Black Eye Galaxy
7) M51--Whirlpool Galaxy
8) M101--eg 5457
9) M3--gc 5272--too amazing!!
10) M97--Owl Nebula. Superb in the 12"!
11) eg 4565--one of the very finest galaxies, edge on!
12) Cor Coroli: double star: 2.9-5.4/20". I see white and yellow. A stunning pair.
Not only is the monthly object list great for star parties or drop-in visitors (who may not fully appreciate the beauty of a 14th mag. galaxy), but I like to use it later in the night when I am tiring of searching out extremely faint objects. It makes a wonderful finale to a night of observing, or before going on to view Jupiter or Saturn, which usually puts a stop to one's night vision. I try to observe the list more than once during the month, too. Nothing like a second (or third) look. So far, these objects have not become part of my formal observing program, and I do not report on them. Perhaps once I have completed the entire cycle of 12 months, I will begin to log their appearance in the 12". Many of them have been reported on with the 8" from previous years.
Last night, the objects were bright enough (except for M101 and M97) to see even as the 6-day old moon was shining, so I actually began my night with this program as I awaited moon set. I also had time to try out another feature of the Push To. I was able to easily find the list on the computer of the best double stars in Bootes, which was beautifully placed later on. I pushed my way through 13 remarkable double stars. My collimation was not perfect, but I managed to split 12 of them! There are many totally amazing double stars in Bootes! It may not have any Messier objects or brighter NGC objects, but it sure has a glorious selection of doubles. The Push To list follows.
1) 1: Mag. 6-9/4".6 separation. White and blue, seen at 100x, 200x.
2) 39: 6-6.5/2".9. Split at 100x, 150x. Both white.
3) 44: 5.5-6/1".5. Viewed at 200x. Both ivory.
4) Epsilon (Izar): 2.5-5/2".9. Viewed at 60x through 200x. Yellow and pale lilac. One of the most beautiful doubles!
5) Iota: 5-7.5/39". 60x. Ivory and lilac.
6) Kappa: 4.6-6.5/13". 60x, 120x. Pale yellow and lilac.
7) Mu: 4.5-6.5/108". Wide pair is yellow and lilac at 60x.
Mu-b: 7-7.5/2". Close pair minute at 100x, whites at 200x.
8) Pi: 5-6/6". 60x, 100x. White and yellow.
9) Xi: 5-7/7". 60x, 100x, 120x. Yellow and orangey-red.
10) Zeta: 4.5-5/0".9 (also a 10.5 comes at 99"). Not split! Wide pair is white and purple.
11) Struve 1785: 7-7.5/2".8. 100x, 200x. Both golden.
12) Struve 1834: 7-7/1".1 200x. Orange pair.
13) Struve 1835: 5.5-7/6".2. 60x, 100x. White and pale lilac.
Now, finding and splitting all of these wonderful pairs in 15 minutes or so is possible using the Push To. Of course I take my time, though, never rushing from object to object, but it is nice sometimes to just be able to see a series of beautiful deep sky objects in wide and various parts of the sky in a short amount of time, and without having to use the finder scope, red flashlight and the atlas (I do enough of that, believe me). By observing the Bootes doubles last night, I also obtained a good sense of the size of Bootes, and exactly how far it extends. By contrast, in a usual night of observing for me I would be confined to one small part of the constellation. So the Push To feature gets me out and about, so to speak.
In conclusion, when I first used the scope last October I thought the Push To would be a feature I would use rarely and only for special searches of objects not near any bright starting point. I do use it for that, but I now really like the monthly features, and also have easy access to all of the finest doubles and variables in each constellation, and some of the finest deep sky objects in any given month.
Mapman Mike
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