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Piero

a curious hammerhead shark asterism?

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A brief session this evening where I could do some preliminary test between my new Vixen 9mm and Delos 8mm with and without powermate. Differences between the views are really limited to my eye (apart from the field of view, weight and size). I finally spotted M102, an isolated Messier Galaxy in Draco. It isn't a difficult target at all, but is a bit distant from the other messier objects. Also tested the Needle galaxy. It is remarkably faint in the 60mm and only a hint of it is detectable.

Hope you enjoy the report.

Piero

 

Date 09/04/2016
Time 21:50-23:40
Location Cambridge, UK
Altitude 12m
Lunar Phase Waxing crescent 15%
Temperature 5C (WSW 11 km/h)
Seeing 3 - Moderate seeing
Transparency 4 - Partly clear
Darkness 19.55
Telescopes Tele Vue 60 F6
Eyepieces Panoptic 24, Delos 12, Delos 8, Vixen SLV 9mm, PM2.5x

Jupiter - Planet 100x, 112x
Vixen 9mm SLV + PM2.5x or Delos 8mm + PM2.5x. I could spot the GRS with both. This was well distinct in the Southern equatorial belt and its colour was dark. The seeing was not sufficiently good to spot the North temperate belt. After eye adaptation, heterogeneities on the two equatorial belts were detectable. These appeared with different colour intensities. Time to time, the Delos seemed to offer a better view, but other times it was the opposite. The image was slightly brighter on the Vixen, but this could have been the different exit pupil (3.6 vs 3.2).

Alpha Gem Dbl Star 100x, 112x
Castor. Distinct split. In the Delos the two stars were yellow and white/blue, whereas in the vixen they were yellow and white.

NGC4494 Com Galaxy 45x
Star hopping from 12 Com. This form an asterism with the adjacent stars which is similar to a hammerhead shark. Following the direction of this shark, there is the prey which is formed by 17 Com. Less than 1 degree ahead there is this galaxy. It appeared faint but detectable with direct vision although averted vision helps particularly for spotting it.

NGC4565 Com Galaxy 30x, 36x, 40x, 45x
Needle Galaxy. Star hopping from 12 Com and then following 17 Com (see NGC4494 for detail). I was able to spot this after about 20 minutes of averted observation. It was incredibly faint. The image was slightly easier to detect with the Vixen 9mm SLV, but this could have been due to the increase in exit pupil. The Panoptic 24mm + PM2.5x (9.6mm) made the galaxy more difficult to spot than the vixen 9mm. Not sure whether the shape was elongated. I could just detect a very faint light which was clearly not a star. At 30x it was invisible.

hammerheadshark.png

 

 

M51 CVn Galaxy 30x
Whirlpool Galaxy. Star hopping from Eta UMa (Alkaid) and the pointers HIP66385 and 24CVn. The two bulges were detectable with direct observation. It was essentially one object with two cores.

M63 CVn Galaxy 30x
Sunflower Galaxy. See M51 and continue the line. Grey smudge detectable with direct observation.

M101 UMa Galaxy 30x
Pinwheel Galaxy. Star hopping from Eta UMa (Alkaid) to Iota and Kappa Boo. Then star hopping for about 3 degrees North West. Faint and large target visible with direct observation. No core was detectable, but it appeared like an extended cloud.

Iota Boo Dbl Star 30x
Asellus Secundus. Together with Kappa Boo, they can be split in the same field of view. Nice double.

Kappa Boo Dbl Star 30x
Asellus Tertius. See Iota Boo.

M102 Dra Galaxy 30x
Easy star hopping from Iota Dra (Edasich). Another grey blob visible with direct observation.

M61 Vir Galaxy 30x
Star hopping from Eta Vir (Zaniah) and then move North in direction of 16 Vir. M61 is faint and not easy to spot initially. Averted vision can help.

M49 Vir Galaxy 30x
I star hopped from M61, but it is possibly from Delta Vir to 31/32Vir. M49 is quite bright and similar to M60 to my eye. Clearly visible with direct vision.

NGC4526 Vir Galaxy 30x
Lost Galaxy. From M49, move 1 degree East until a triangle is found. NGC4526 is located in this triangle. It is faint and visible only with averted vision.

NGC4535 Vir Galaxy 30x
McLeish's Object. See NGC4526 for star hopping. It is placed outside the triangle of stars found 1 degree East from M49. This object is very faint and averted vision is required.

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Super session again, Piero.  I love what you're getting out of the TV60.  

Like the Hammerhead spot - I'll keep an eye out for that.

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Great taking advantage of that clear sky last night!  From your testing it doesn't sound like there is a lot of difference between the Vixen and Delos, as they are both solid performing.  That must be a luxury to swap from quality to quality :)

I caught my zzzzzzz's early and didn't start till the wee hours, but it sure looked like a nice evening.  Great dedication on the Needle!

clear skies

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8 minutes ago, Special K said:

Great taking advantage of that clear sky last night!  From your testing it doesn't sound like there is a lot of difference between the Vixen and Delos, as they are both solid performing.  That must be a luxury to swap from quality to quality :)

I caught my zzzzzzz's early and didn't start till the wee hours, but it sure looked like a nice evening.  Great dedication on the Needle!

clear skies

Thanks Kevin :)

I need a bit better seeing for testing the vixen vs the delos. I should at least see the North temperate belt and the polar regions. That would be a good test. 

Said this, I didn't buy this Vixen 9mm as an alternative to the Delos 8mm. The fact is that:

- I feel the combination delos+pm2.5x just too heavy for the tv60 focuser. Maybe this is fine but I don't want to risk.

- With the TV60 the vixen plus pm2.5x gives a vixen 3.6mm and 100x which allows me to leave it mount on the power mate when observing in the night. The weight is a bit less of a delos.

- I wanted a low power eyepiece for solar observation to regularly see granulation. The Nagler 7 is fine for this, but it is ways more expensive and to me the vixen has an edge on the Nagler. I don't really fancy the Delos on solar. The view it deliver is fantastic, but its eye placement is uncomfortable to me for, and only for, this target.

- I wanted a high power eyepiece for solar. The Nagler 7mm gives 129x with the tv60 which is quite a lot and doesn't reveal much more detail than 100x magnification. So again powermating a 9mm would generally be more useable.

- the trio pan24, vixen 9 and vixen 5 are perfect for very light grab and go and all fine if I keep my spectacles. The Delos are not grab and go, the Nagler t6 are not suitable with spectacles.

- having the vixen 9mm allows me to sell the Nagler 7mm and 3.5mm without losing anything really. This actually saves some money.

Put all this reasoning together a vixen slv, 9mm or 10mm was suitable for this. I went for the 9 for the slightly higher magnification and because it's a better match with the vixen slv 5mm which I already have. To me, 12-8, 11-7, 10-6 and 9-5 have a happy marriage under an F6 house. :)

That's it! 

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Brilliant report Piero!

You found and saw the Needle! and in a 60mm scope!- congrats:icon_biggrin: This is another object that opens up a crackerjack box of surprises :grin: Great observing- and steady dedication to viewing this object-20 minutes...in averted vision... I would say you are now hooked on DSO!:thumbsup:

It is interesting to note that the SLV might be better on this threshold object for you- more testing and more objects would be nice  ( I hope, more reports). If you can also compare contrast on non threshold galaxies it would be great.

You are now crowding Vmag 10 galaxies...your object recognition is getting honed, have you tried NGC 6939 and NGC 6946 in Cepheus yet? NGC 7160 is also a really good one to sit and stare at for a long while... Its almost time for you to get up North and meet up with someone who has a large dob under 21+ mag skies... only a couple of hours drive from you to it Piero!:grin:

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Piero

So looking at your excellent recent reports..based on my 100mm binocular observations......to fill in the galaxy gaps... maybe next up might be:-

NGC 4214 / 4251 / 4414 / 4605 / 4631 / 4725 / 5322 / 5363 / 6503 (UMA/COM/CVN/VIR/DRA)

and of course M83!

These should all be relatively accessible at the moment in the sky..

Mark

P.S your observations regarding direct and averted vision etc are very much consistent with my experience with the 100mm bins at x25 although the galaxies are usually very small at x25!

 

 

 

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2 hours ago, jetstream said:

Brilliant report Piero!

You found and saw the Needle! and in a 60mm scope!- congrats:icon_biggrin: This is another object that opens up a crackerjack box of surprises :grin: Great observing- and steady dedication to viewing this object-20 minutes...in averted vision... I would say you are now hooked on DSO!:thumbsup:

It is interesting to note that the SLV might be better on this threshold object for you- more testing and more objects would be nice  ( I hope, more reports). If you can also compare contrast on non threshold galaxies it would be great.

You are now crowding Vmag 10 galaxies...your object recognition is getting honed, have you tried NGC 6939 and NGC 6946 in Cepheus yet? NGC 7160 is also a really good one to sit and stare at for a long while... Its almost time for you to get up North and meet up with someone who has a large dob under 21+ mag skies... only a couple of hours drive from you to it Piero!:grin:

Thanks Gerry! :) I agree with you about the test on the Vixen. Possibly M60, the Leo triplet and M3/13 would be good as test cases. I observed NGC 7160 last year and it was a real gem to me. Also visited NGC6039 and 6946. I didn't spot anything for the galaxy and in my log I wrote that I was not able to spot the open cluster. Weird as it is 7.80 mag. Possibly I was in a wrong location, or the magnification I used (28x) was just to low. I'll go back to this pair when they are better placed in the sky. Thanks a lot!

 

1 hour ago, mdstuart said:

Piero

So looking at your excellent recent reports..based on my 100mm binocular observations......to fill in the galaxy gaps... maybe next up might be:-

NGC 4214 / 4251 / 4414 / 4605 / 4631 / 4725 / 5322 / 5363 / 6503 (UMA/COM/CVN/VIR/DRA)

and of course M83!

These should all be relatively accessible at the moment in the sky..

Mark

P.S your observations regarding direct and averted vision etc are very much consistent with my experience with the 100mm bins at x25 although the galaxies are usually very small at x25!

Thanks Mark! :) 

You provided me with a nice list of galaxies and I agree that they might be feasible albeit at the limit. I noted them down and will go through them carefully to see what pops up! Thanks very much. Hopefully M83 will be spotted when I will be in Italy but with the 200mm :). Unless I go to the countryside by bike, there is not chance to see this from this garden due to the trees. Not even sure whether M68 will be accessible. While in Draco looking for M102, I tried to spot NGC 5907 (Mag 10.40) but did not succeed, so I reckon 10 - 10.50 mag should be the very limit for this 60mm from this location (assuming feasible object surface brightness of course). 

Did you observe those galaxies with your 100mm from a dark sky or about 5.5 mag? It's interesting to see how you spotted those targets with more aperture, while I spotted (some of) them with more magnification (25x100 vs 45x60). :)

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Piero

That list are the galaxies I have viewed with direct or averted vision in my 100mm bins in mag 5.5 skies that are riding high in the skies at the mo that were not on your reports.

That 6946 is like a faint smaller m74...tough even in a 10 inch Dob in mag 5.5 skies.

The low magnification of the binoculars does restrict the magnitude limit a lot. With power your 60mm does seem to pretty much match the 100mm bins from your descriptions. I needed to use av on the same ones as you and saw the galaxies with dv when you did.

Keep the reports coming.

Clear skies.

Mark

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Thanks Mark again and for letting me know the reason why I didn't spot NGC 4946 that time! :) 

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