77 replies to this topic

[newbeeDavid]

My grandson wants to view galexies, I am trying to see how, I have an Orion 8" skyquest xt dobsonian that should be able to see magnitudes in the 10-12 range. Going by using stars in constellations  for a starting point are there other help aids?

[Ljubo]

https://youtu.be/6-_58mSGz1Q

[RyanSem]

First, understand that "seeing" a magnitude 10 galaxy is sort of akin to seeing a bit of fog on your bathroom mirror after a shower. And the lights are turned off. It's going to be pretty darn faint. 

 

But - the time-tested method of finding these objects is by star-hopping. Bonus points, you will actually learn something about the night sky, and not just get a computer/phone do all the work for you. There's something important about that. 

 

Star hopping is basically as you'd imagine. Say you want to find Bode's Galaxy (M81). You see on Stellarium that Bode's is near the Big Dipper. So, start by finding the Big Dipper. Then you notice it's closest to the "tip" of the dipper. So now you go to your telescope, choose the highest number eyepiece you have (for the widest field of view), and find the same star through the telescope. If you have a finder scope it's even easier since the view should be even wider. 

 

Then go star by star until you get to the area you know the galaxy is supposed to be in. Depending on the type of scope you're using, left might be right and right might be left when going from the star map on your phone back to the telescope. This takes a lot of patience and is somewhat of a learning curve. Don't be discouraged if you can't see things right away. But choosing brighter objects like M81, M42, M31, etc will help you hone your skill and give you the payoff you're looking for. Once you're in the right region, hopefully you can see the galaxy, but again, for those 10-12 magnitude objects you probably will barely see the faintest wisp of something at best. 

[Sebastian_Sajaroff]

That telescope will give satisfying views of galaxies as long as you use it under a dark transparent sky (no city lights, Moon, fog, haze, smoke or smog).
Don’t waste your time trying to observe mag 10 galaxies on an 8" from the city or under a poor night.
Make sure you have realistic expectations on how galaxies look visually on a telescope. Feel free to google “sketch of M94" (or M81, M82, M33, M64, etc.), sketches are much closer to visual reality than photographies.

[newbeeDavid]

Thanks what you've told me is somewhat how I assumed the best learning and finding skills without an app would be and the tip on darker the better is helpful. I've been pointed to astro hopper as a tool and it seems slightly helpful for getting to a region however seeking with just star locations builds the mental database. 

[WISDOC]

The above advice is all great. You can get on the computer and print free star charts to use as a map to the galaxies you choose. Stay with the brighter galaxie for now. You can check the sketching forum here to get an idea what to expect. Some members here are very good at sketching what they observe. Totally forget about large clearly defined galaxies like you see on the internet. Not gonna happen with earth based private telescopes. When you do find a galaxy though {especially the first one} it's like a right of passage with a scope. Good hunting and have fun.

  Clear skies and keep looking up. Doc

[A Star Geezer]

Down load stellerium to your cell phone, it will help you see what is in the sky around you. Here is how to use it

https://youtu.be/GnV...BB0u2kD3xq15epz

[woldsstargazer]

With a Dobsonian mount, star hopping is your only manual option. It helps to have a right angled finder scope. If the mount was an equatorial, you could use setting circles. 

[david_od]

I try to plan my observations with Stellarium. I either memorize some specific star patterns if they are easy, or print out inverted screen captures (there is an option for this in the Configuration > Tools > Screenshots section). I usually print out a slightly large contextual field of view and then one or two eyepiece simulation fields of view if I see it's going to be a bit hard to find. I use a dim red flashlight with the maps.

 

If I'm certain of an approximate observing date and time, for my dobsonian maps I enable the alt-az coordinates grid, so I can use star patterns that will be either over/under the object of interest or to its left or right, remembering that things will be inverted. Stellarium also allows you to invert the view in any of these directions if needed. Or you can just rotate in 180° your printed chart.

I customize Stellarium's Telrad tool to simulate the fields of view of my finderscope and three other eyepieces, so I can design navigation paths using star patterns.  I find this much more practical than using the eyepiece field of view simulator. I suggest adjusting the actual fields of view to what you can actually see with your eyepieces. Sometimes they will differ from theoretical calculations.

 

With the telrad/eyepiece tool sometimes I use two or three reference stars or star patterns that should be within a certain field of view so I know my object of interest is going to be somewhere there.

I modify my limiting magnitude or add some light pollution to the sky, so I don't get lost with too many stars in the map.

When it's really difficult in a zone with too few brightish stars or if one feels lost, one can use Earth's rotation to determine the RA/Dec directions if needed, or you can even let a certain object drift to your field of view, if you know it's not too far from a well established reference point.

 

 

Since you want to observe faint objects, there are a few additional important considerations. I know your question is not about this, and maybe you know most of these suggestions, but I think there is no harm in mentioning them:

- Since they are faint objects, you require dark skies. While you can certainly *detect* galaxies as small faint fuzzy objects in light-polluted skies (I've observed the Sombrero Galaxy/M104 under Bortle 8-9 skies, but only as a barely detectable smudge). You need dark skies for best results, or adjust your targets and expectations to your possibilities.

- Objects high in the sky will look better, as there is less atmosphere in the path (technical term: "air mass"). Choose bright galaxies that are high in the sky if possible. Of course some of the brightest ones might not be so high up and still be great targets.

- Edge-on (or close to edge-on) galaxies will be, in general, easier to detect.

- While applications like AstroHopper will help, since you want to observe faint objects you may want to avoid screens, or make "pirate patches" to cover the observing eye. Try to adapt at least the observing eye to darkness for at least 30 minutes, if possible. Any bright enough light will reset this.

- Start with low magnification to find the objects, but don't be afraid to use some magnification to get to a range within 3-2 mm exit pupil or even a bit less for some objects. For the typical 8" f/6 or f/5.9 dob this will be an eyepiece within 18-12mm. A 10 or 9mm might still work great for some targets.

- Practice peripheral vision with your grandson.

- Softly tapping the telescope tube can help you to detect the galaxies as you'll see them move within the field of view. This might also help you detecting more details in them.

- Try to observe while seated and wearing appropriate clothes for the weather.

- Try to spend some time with your targets befre moving on to the next one, if possible. Try different magnifications for each target.

Edited by david_od, 09 February 2025 - 06:55 PM.

[Jon Isaacs]

How dark are your skies? Can you see the Milky Way in the summer?

 

Jon is

[sevenofnine]

Your first goal should be M31, the Andromeda Galaxy. It's the largest one visible and most impressive. The easiest way to locate it is with binoculars first. Use Stellarium or SkySafari to get your bearings then zero in on it with the binos. After that it's a matter of coordinating the view through the binos with what you see in your widest eyepiece in your scope. It takes time and patience...Good luck! 

Edited by sevenofnine, 09 February 2025 - 08:05 PM.

[ShaulaB]

It's like a sport. Practice, practice, practice with star hopping.

 

An 8 inch Dob should fit into most vehicles for travel to darker skies. There are no filters to enhance galaxies.

 

M31.

M81 an 82 in Ursa Major.

[newbeeDavid]

Andromeda is my grandsons next wanted target he's upset about losing Saturn til the fall his next favorite is Jupiter and it's moons.

[BrentKnight]

There are a couple books that you can get that are very useful for learning the art of star hopping and visual DSO.

Turn Left at Orion by Guy Consolmagno and Star-Hopping for Backyard Astronomers by Alan MacRobert.

Both can be found used for a reasonable cost.

[Jay_Reynolds_Freeman]

My website has an old article about finding things using star-hopping and paper charts. Much of what I say about paper charts carries over to charts on a computer console, though I think there is still a place for paper charts and hard-copy star atlases in amateur astronomy today.

 

Clear sky...

[AstroVPK]

My grandson wants to view galexies, I am trying to see how, I have an Orion 8" skyquest xt dobsonian that should be able to see magnitudes in the 10-12 range. Going by using stars in constellations for a starting point are there other help aids?

Try locating M31 first. Once you've found M31, look for M32 and then M110 next to M31. Seeing M110 requires decently dark skies - if you have trouble seeing M110, try moving to a state park away from city lights.

[Dave Mitsky]

There are star-hopping tips for locating some of the most prominent Messier galaxies in my post at https://www.cloudyni...mers/?p=4592919

 

[Dave Mitsky]

There are star-hop charts to a number of Messier and NGC galaxies posted at https://www.skyledge.net/index.htm

[Dave Mitsky]

Andromeda is my grandsons next wanted target he's upset about losing Saturn til the fall his next favorite is Jupiter and it's moons.

M31 is sinking into the western sky.  Start looking shortly after the sky gets dark when the Moon is no longer a problem. 

https://www.skyledge.net/index.htm

 

[newbeeDavid]

Thank you Dave I started reading your post https://www.cloudyni...mers/?p=4592919 the information has me and my grandson locating and planning on where we will view or try to view some of these targets I am working on the maps while he searches what to view, being eight the choices are a little to extensive but I am narrowing the field thanks for the data. from the back yard eastern sky is the least light polluted which seems to hold us to planets and occasional discoveries which the search keeps his interest. 

[Dave Mitsky]

Thank you Dave I started reading your post https://www.cloudyni...mers/?p=4592919 the information has me and my grandson locating and planning on where we will view or try to view some of these targets I am working on the maps while he searches what to view, being eight the choices are a little to extensive but I am narrowing the field thanks for the data. from the back yard eastern sky is the least light polluted which seems to hold us to planets and occasional discoveries which the search keeps his interest. 

Spring in the northern hemisphere is galaxy season.  M81 and M82 can be seen in the north-northeastern sky currently before it gets too late.

https://www.skyledge...ssier81-hop.htm

[WISDOC]

  woldstargazer you can indeed use setting circles on a dob. I use them all the time. There is a VERY long thread here about them that started around 2008 I believe. They are easy, accurate, and many people have proven it's a faster accurate way to stargaze than some "modern" methods. You should check it out.

  Clear skies and keep looking up. Doc

[newbeeDavid]

Doc,

I have searched for woldstargazer and find only your reference do you have a link to the information?

 

David

[WISDOC]

Seventh post down from your original one.

[WillR]

Andromeda is my grandsons next wanted target he's upset about losing Saturn til the fall his next favorite is Jupiter and it's moons.

After Andromeda, I would look for M81 and M82. All other galaxies will be quite faint. 
 

Your grandson probably wants to see galaxies because it is one thing he has heard of along with the planets. When I started observing, I had no idea there were such things as open clusters, globular clusters, planetary nebula, and emission and reflection nebula. Not to mention double stars.

 

I would take this opportunity to introduce these to him, many of which are far brighter most all galaxies. For a good representative target in each try:

 

1. The double cluster in Perseus or the Pleiades for an open cluster.

2. M13 in Hercules for a globular cluster. (You may have to wait a month or two)

3. The Ring nebula in Lyra for a planetary nebula. (Again, not well placed now) 

4. M42 in Orion for an emission nebula.

5. For a double star, look at Mizar, the center star in the big dipper’s handle with high magnification.