Neptunes Moons

[Barry-W-Fenner]

Hi all,

In regards to viewing Neptune. I understand it is possible to see its largest moon Triton with the correct seeing conditions and setup. But I was wondering if it is possible to see any of Neptune's smaller moons such as Proteus with bigger scopes.

I am just curious more than anything to know what can be seen through larger scopes. In truth I am  still struggling to find Neptune myself 🙂🙂

 

Baz

[Stu]

At mag 19.5, I think it is beyond most normal amateur scopes, even say a 30". I checked the limiting magnitude for this size and even under a perfect sky it is 'only' mag 18.2.

Best chance would probably be some form of video astronomy with a sensitive camera, I recently saw an image of 4 moons around Uranus with this sort of kit.

[Barry-W-Fenner]

3 hours ago, Stu said:

At mag 19.5, I think it is beyond most normal amateur scopes, even say a 30". I checked the limiting magnitude for this size and even under a perfect sky it is 'only' mag 18.2.

Best chance would probably be some form of video astronomy with a sensitive camera, I recently saw an image of 4 moons around Uranus with this sort of kit.

Thanks for the information Stu, Now I know what is possible. I am still on the hunt for Neptune when we get a clear night I will try again. I am having difficultly finding it at the moment with my lack of experience.

Baz

[Stu]

1 hour ago, Barry-W-Fenner said:

Thanks for the information Stu, Now I know what is possible. I am still on the hunt for Neptune when we get a clear night I will try again. I am having difficultly finding it at the moment with my lack of experience.

Baz

Neptune is getting a little low now but should still be doable if you catch it early.

If you can find Phi Aquarii then Neptune is still within a degree of this star.

If you have a Telrad or similar finder then you can pop it centred on Phi Aquarii as in this diagram and you should be able to then at least position it over where Neptune should be even if you can't see it through the Telrad, and it should appear in the scope eyepiece.

[Barry-W-Fenner]

4 minutes ago, Stu said:

Neptune is getting a little low now but should still be doable if you catch it early.

If you can find Phi Aquarii then Neptune is still within a degree of this star.

If you have a Telrad or similar finder then you can pop it centred on Phi Aquarii as in this diagram and you should be able to then at least position it over where Neptune should be even if you can't see it through the Telrad, and it should appear in the scope eyepiece.

Thank you Stu, I appreciate your assistance.  I can locate phi Aquarii but seem to be having difficulty finding Neptune. I have been looking around that area of sky with my 8mm BST eye piece to try and locate it with the aim of increasing the magnification with my 5mm BST eye piece. no joy yet but I will keep hunting. 

I did put a rigel finder on my xmas list and apparently have one waiting at a family members house! Things should get easier when I start using this.

 

Regards

 

Barry

[Stu]

6 minutes ago, Barry-W-Fenner said:

Thank you Stu, I appreciate your assistance.  I can locate phi Aquarii but seem to be having difficulty finding Neptune. I have been looking around that area of sky with my 8mm BST eye piece to try and locate it with the aim of increasing the magnification with my 5mm BST eye piece. no joy yet but I will keep hunting. 

I did put a rigel finder on my xmas list and apparently have one waiting at a family members house! Things should get easier when I start using this.

 

Regards

 

Barry

Good stuff. Good luck!

Have you managed Uranus yet? It is brighter and higher in the sky so might be a good one to start with?

[Barry-W-Fenner]

1 minute ago, Stu said:

Good stuff. Good luck!

Have you managed Uranus yet? It is brighter and higher in the sky so might be a good one to start with?

Unfortunately not.  I have tried on a couple of occasions but I seem to have a fair amount of light pollution in the area of sky where Uranus is located. I can barely see the star constellations Aries and the vertical star line of Pisces. I am hoping the regal finder will help me locate Uranus also. When I look through my right angle finder I am struggling to understand what I am looking at in that area of sky.   Both Uranus & Neptune are both providing me with a challenge!

Regards

Baz

[Stu]

1 minute ago, Barry-W-Fenner said:

Unfortunately not.  I have tried on a couple of occasions but I seem to have a fair amount of light pollution in the area of sky where Uranus is located. I can barely see the star constellations Aries and the vertical star line of Pisces. I am hoping the regal finder will help me locate Uranus also. When I look through my right angle finder I am struggling to understand what I am looking at in that area of sky.   Both Uranus & Neptune are both providing me with a challenge!

Regards

Baz

Yes, I guess Uranus is a bit out in the middle of nowhere at the moment, and if you can't see the nearby stars easily then star hopping is tough.

Do you have Skysafari? If you set this up to match the field of view, orientation and limiting magnitude through your scope with a low powered eyepiece, then you can use this to star hop from a star you can find in the scope.

[Barry-W-Fenner]

10 minutes ago, Stu said:

Yes, I guess Uranus is a bit out in the middle of nowhere at the moment, and if you can't see the nearby stars easily then star hopping is tough.

Do you have Skysafari? If you set this up to match the field of view, orientation and limiting magnitude through your scope with a low powered eyepiece, then you can use this to star hop from a star you can find in the scope.

I do have Skysafari and have just had a look. I found the Star Limiting magnitude setting and had a quick play. that is a huge help!  I have lowered it down to 3.0 which is about what i can see roughly in that direction, Thank you.

I cant seem to see the Field of View setting though. I will have another look shortly.

Cheers Stu!

[Stu]

28 minutes ago, Barry-W-Fenner said:

I cant seem to see the Field of View setting though. I will have another look shortly.

Assuming you have the Plus version at least, you have to set your kit up in the equipment section (scopes and eyepieces) , then can choose fov circles. It varies between version 5 and 6 as to where this is done but it is possible in both. Touch the top right of the screen and you get a drop down where you can turn the top three circles on and off quickly, or zoom to that fov by tapping the number itself.

Touch top left of screen to get the magnitude drop down.

These are from SS6, slightly different to 5 but similar functionality in both.

[johnturley]

1 hour ago, Barry-W-Fenner said:

Unfortunately not.  I have tried on a couple of occasions but I seem to have a fair amount of light pollution in the area of sky where Uranus is located. I can barely see the star constellations Aries and the vertical star line of Pisces. I am hoping the regal finder will help me locate Uranus also. When I look through my right angle finder I am struggling to understand what I am looking at in that area of sky.   Both Uranus & Neptune are both providing me with a challenge!

Regards

Baz

If your location suffers from significant light pollution, then it is unlikely that you will spot Triton visually. At my location have been unable to spot it visually even with my 14in Newtonian, through which in theory it should be quite easy to spot. I don't whether the main reason for this is due to light pollution, or my declining visual acuity at 70 years of age, although I have had a recent cataract operation in my right (observing) eye which should improve things. Also I can't make out the constellations so clearly, or the milky way, or so many of the Pleiades as I could back in the 1960's when light pollution was not so bad, but I could still make out the milky way clearly from dark sky locations such at Mt Teide Tenerife, or from parts of South America on the recent eclipse trip. 

I have however picked up Triton photographically, by accident as it happens, when I photographed the close conjunction of Neptune and Mars last year.

John  

Edited January 10, 2020 by johnturley

[Barry-W-Fenner]

Stu - Your a gent, I will read through the above tonight when i have the time and set the app up accordingly 🙂

John - Thank you for the heads up regarding Triton, At least this gives me another great excuse to get to a dark site

 

[John]

I have seen Triton on quite a few occasions from my back garden which has moderate but not severe light pollution. My 12 inch dob shows it reasonably easily but I find that high magnifications (300x plus) are needed to help the moon pop out of the background sky. Sometimes a form of averted vision helps spot it as well. I have managed to see Triton a couple of times with my 130mm triplet refractor as well but with that smaller aperture spotting the faint point of light fairly close to Neptune needs better seeing conditions.

With my 12 inch dob I have also managed to see a couple of Uranian moons - Titania and Oberon. There are 2 others which I should also theoretically be able to pick up with that scope but I have not managed that so far. The Uranian moons are a touch dimmer than Triton and Uranus is brighter and a larger disk than Neptune all of which adds to the challenge.

 

[Barry-W-Fenner]

11 hours ago, John said:

I have seen Triton on quite a few occasions from my back garden which has moderate but not severe light pollution. My 12 inch dob shows it reasonably easily but I find that high magnifications (300x plus) are needed to help the moon pop out of the background sky. Sometimes a form of averted vision helps spot it as well. I have managed to see Triton a couple of times with my 130mm triplet refractor as well but with that smaller aperture spotting the faint point of light fairly close to Neptune needs better seeing conditions.

With my 12 inch dob I have also managed to see a couple of Uranian moons - Titania and Oberon. There are 2 others which I should also theoretically be able to pick up with that scope but I have not managed that so far. The Uranian moons are a touch dimmer than Triton and Uranus is brighter and a larger disk than Neptune all of which adds to the challenge.

 

Hi John 

Thank you for your for the information, it is great to have an understanding of what one can realistically see.  Hopefully one day with the correct equipment and experience I might be about to enjoy done of these sights.

For now i will be lucky to find both Uranus and Neptune,  with all the above advice I am sure I will see them soon. I have just for my regal finger which should assist in localisation, I will then use my right angle finder to confirm.   I assume you can identify these planets in the finder? Does that give enough magnification?  What sort of mag will be best to view these planets at the eye piece?

A bit off topic, I was looking at your great scope in the "show me your dob" thread. And really like your build/setup. I left a couple of questions, if you get the time would you mind answering and giving your opinion. Your advised would be greatly appreciated.

 

Thank you 

 

Baz

[John]

Both Neptune and Uranus can been seen in optical finders from 30mm and upwards in aperture. They are just star-like points in finders though. At around 50x and upwards Uranus shows a disk and for Neptune 150x is needed because its disk is around half the angular size of Uranus.

Feel free to message me with any questions on my scope.

 

[Stu]

2 hours ago, Barry-W-Fenner said:

I assume you can identify these planets in the finder? Does that give enough magnification?  What sort of mag will be best to view these planets at the eye piece?

You will be able to see the planets in the finder but it depends how bad your LP is as to whether you can identify enough nearby stars to know you have got the right one. A low power eyepiece in the scope may be useful once you think you are in the right place, then switch to higher power to see the disk.

[Barry-W-Fenner]

34 minutes ago, Stu said:

You will be able to see the planets in the finder but it depends how bad your LP is as to whether you can identify enough nearby stars to know you have got the right one. A low power eyepiece in the scope may be useful once you think you are in the right place, then switch to higher power to see the disk.

Many thanks again Stu. 

 

[Barry-W-Fenner]

21 hours ago, John said:

Both Neptune and Uranus can been seen in optical finders from 30mm and upwards in aperture. They are just star-like points in finders though. At around 50x and upwards Uranus shows a disk and for Neptune 150x is needed because its disk is around half the angular size of Uranus.

Feel free to message me with any questions on my scope.

 

Thanks John, I will drop you a message asap 🙂

 

Regards

[Barry-W-Fenner]

Quick update. I managed to fit my rigel last night which was excellent! I can now quickly locate targets with Zero magnification which is a great help. This complements the Right angle finder nicely. The only down side is looking up around the zenith area through it. My back cant take it! 🙂 

I started to search for Uranus but between intermittent cloud and the LP in this particular area of sky I came up short.  I keep singing U2 to myself, "I still haven't found what im looking for" 🙂

Very encouraging signs using the rigel though, It was a huge help in locating other stars and targets, A valued addition. 

 

Baz

 

[Barry-W-Fenner]

Evening all.

I've just come in from about an hour and a half and am chuffed to bits as I found uranus for the 1st time. Seeing that tiny perfectly round greenish disc made me fist pump the air! The sky tonight is unbelievably good here, very clear which made star hopping a joy. Really pleased I can tick this one off the list.

I also had a look at andromeda and the cat eye nebula. Also the Pleiades and double cluster look amazing. I assume seeing is really good as they were Crystal clear. Orion looked stunning as always. 

 

Baz

Edited January 21, 2020 by Barry-W-Fenner

[John]

Nice one Baz !

It was good here until about an hour ago then a cloud layer came across and spoiled things. Not that I've been able to do more than have a quick peek with my 11x70 binoculars just before loosing the clear sky. Had to be sociable with relatives this evening.

 

[Stu]

Well done Baz, a great feeling when you finally find something that's been eluding you.

Skies were good here for a few hours. Transparency was very good although seeing less so. Clouded over now so am all packed up.

[Barry-W-Fenner]

Thanks gents, Much appreciated.  I was so happy to find Uranus finally. It has taken me a little while but we got there in the end. I think the face that it took me a while to locate made it extra special. It really did help that the sky seemed to be on my side for a change. As you have both mentioned it was very clear from about 7 to 9 here. I had to pack up as I was starting to get very cold. I looked outside around 10ish wondering what I was missing and it had all clouded over! I couldn't believe how quick the came happened.  Ironically I would usually wait as late as possible to go, If I had done that I i would have had a duff evenings viewing.

Baz

[Stu]

Keep an eye on Sat24 and you will see which way the cloud is moving.

[Barry-W-Fenner]

On 20/01/2020 at 08:04, Stu said:

Keep an eye on Sat24 and you will see which way the cloud is moving.

Hi Stu,

Only just noticed your post, Sorry. What is Sat24? I am not familiar with this.

Thank you

Barry