06 August 2018, FOA-60

Lyra’s Messiers and Dusty Mars

Telescope: FOA-60 (60/530mm doublet)Eyepieces:

ATC40K - ATC Kellner, f=40mm, (13×, 3.1◦)XF12 - Pentax XF12, f=12mm (44×, 1.4◦)XO5 - Pentax XO5, f=5.1mm (104×, 25′)

Time: 2018/08/06 20:50-22:10UTLocation: RıcanyWeather : Very good transparency.Seeing : Average, near horizon bad.Mount : Zeiss T1Accessories: Baader 1.25” zenith prism

This is very hot and dry summer. On Sun-day, we were experiencing finally a mild tem-perature drop, from regular 34 ◦C down to28 ◦C. More importantly, the temperaturedrop was accompanied with some rain, whichcleared the dust from dry atmosphere. Thisresulted in a nice sky clear all the way downto horizon. I was able to see the major starsin Sagittarius. A rare sight.

I had this summer numerous short plane-tary sessions with my new acquisition, Taka-hashi fluorite doublet FOA-60Q. The versionwith the extender has similar specificationsas my trusty Telementor. To get a tasteof shorter refractor, I was observing recentlywithout the extender. Riding on Telementormount, it is very light and enjoyable setup.

I started at twilight with double stars.First came Kuma, ν1,2 Draconis. This pairof equal stars is hypnotizing at 13×. Its nick-name, Dragon eyes, is indeed appropriate.Both stars were of same brightness and whitecolor. Like twins.

Nearby Arrakis, µ Draconis, was anotherequal pair. This one is more tight, StelleDoppie gives current separation of about2.6′′. At 104×, I saw two almost touchingequally bright discs at PA∼ 10◦. They wereagain white, with slight indefinite color con-trast. Sometimes one component seemed tobe a little bit bluer than the other, in fewsecond it was opposite.

There was nothing exceptional on Saturnas seeing was definitely not good. I got justa regular sight as in previous numerous ses-sions.

Then came Lyra. The main target ofthe night was globular cluster NGC 6779(M56). It is placed in wonderful star fieldand I can enjoy this cluster in all my tele-scopes, from 8 × 40 binocular up to 150mmCassegrain. Aperture of 130mm is enough toshow many individual stars scattered acrossthe whole cluster surface.

I wanted to capture this beauty on asketch. For this, I prepared a template withbrighter stars. In the field, I added all stars Icould see with a reasonable effort at 44×. Inthe vicinity of M56, I went a little bit deeperusing 104×. In 40 minutes, I filled more thanhundred stars. I noticed some colors for thethree brightest ones. One star was deep or-ange. This was red giant of spectral typeM0 III (BD+30 3491) as I found out later.The other two were bluish.

As for the M56, it was at 44× a small cir-cular glow with a mild central concentrationand with a faint halo. Higher magnification104× showed some hard to detect mottlingand few nearby faint stars. I’m not sure thesewere the cluster members.

I also recorded perceived variations in skybackground. These were very difficult to no-tice and even more difficult to put them onsketch. Don’t take them too seriously. Thiswas my best attempt.

At home, I put all the stars into computerto create a template for the final sketch. Ineeded several attempts to obtain satisfac-tory capture of sky background. I also addedthe observed colors.

Mars was still behind trees which gave me atime to sketch the second Messier in Lyra, fa-mous Ring nebula NGC 6720 (M57). Thesketch went much faster as there were notthat many stars in the narrow field of view ofPentax XO5 eyepiece. I paid special atten-tion to V = 13.0 star at the eastern edge ofnebula. I glimpsed it only twice for very shortmoments, even below what I would considernormally a detection threshold. It looks likemagnitude 13.0 is limit of my vision in this60mm refractor. The star is much easier in63mm Telementor. I saw it on many occa-sions and with more certainty.

Planetary nebula was at 104× nice brightring, more like two touching half-circles.There was definitely some nebulosity in-side. The ring was showing some light blue-greenish color at 13× and 44×. I tried to putit on the final sketch.

Finally, Mars got above the trees. Seeing

was horrible, after five minutes of sketchingand observing I got for a fraction of seconda very sharp image and I realized that I wasstarring all the time at Syrtis Major. Thiswas confirmed immediately after the sessionin WinJUPOS.

Mars could have used some rain as welldefinitely. The atmosphere was still quitedusty and darker albedo features were paleand hard to notice. In addition, I saw whitercaps on both poles. Here is the color versionof the original pencil sketch.

The rest of the session was more relax-ing. I visited quickly NGC 224 (M31).Both companions, NGC 221 (M32) andNGC 205 (M110), were visible at 13×, al-though I was just guessing the position ofM110. Power of 44× showed this galaxy withno problem. I also had a short look at nearbygalaxy NGC 404 (Mirach ghost). It was in-visible at 13×. I saw at 44× a small glow justoutside the Mirach’s halo.

Then I decided to pay a short visit to h andχ Persei, my first view with this scope. Itwas so perfect at 13×. So many tiny colorfulstars!

I was scanning the sky around, trying tofind out the nearby cluster Stock 2. I wastoo lazy to open Pocket Sky Atlas that I hadout with me. I was surprised to see actuallythree cluster candidates and I made a sketchto identify them later on.

There were two large clumps of stars. One,made of numerous fainter stars, was actuallyStock 2. I noticed that at the eastern edgeof Stock 2 there was another, smaller group-ing of stars, which was looking as a separateopen cluster. I have found out from Inter-stellarum Deep Sky Atlas that I made anindependent discovery of open cluster withdesignation ASCC8. It is one of 109 galac-tic clusters found by N. V. Kharchenko andcolleagues by analyzing the ASCC-2.5 (All-Sky Compiled Catalogue of 2.5 Million Stars)data. WEBDA puts this cluster to the dis-tance of 2200 pc, much further than 303 pc incase of Stock 2. It is also much younger, be-ing only 6 million years old compared to 170millions of Stock 2. So, unlike the case of hand χ Per, it is just a random pair.

The third candidate was west of realStock 2. It was made of brighter stars andit was a little bit larger than Stock 2. Atthe eyepiece, I thought that this was actuallyStock 2 I was looking for. There is no clusterplotted in the Interstellarum Atlas in this po-sition. Although the star group stands quitewell even in the atlas. There is just a smallopen cluster NGC 743, which I did not no-tice at 13×. A little bit further away from hand χ Per, I run on a forth cluster which Iidentified as NGC 663.

At the end, this blind cruising was not onlyrelaxing but quite rewarding as well.

Alexander Kupco