Jump to content

Banner.jpg.b83b14cd4142fe10848741bb2a14c66b.jpg

lunator

Moderators
 View Profile  See their activity

  • Posts

    7,974

  • Joined

  • Last visited

 Content Type 

Posts posted by lunator

    The Moon, Jupiter and Saturn with a couple of Novae and doubles 17/09

    in Observing - Reports

    Posted

    The skies were looking ok last night. I thought I would try and get a couple more observations in on the Novae. 


    I set up the ST80 on the photo tripod. Conditions weren’t brilliant, there was still some cloud around and although the moon was low behind some houses it was still washing out a large part of the sky.


    1st stop Saturn just to check finder scope alignment etc. It was easily found in the 25mm (x16). At higher mags the image was “swimming” it was like looking through running water. Un-deterred I decided to head 1st to RS Ophuchi.


    RS Ophuchi – Found it ok in the 25mm but needed 12.5mm (x32) to see more clearly. 
    RS Ophuchi brightness was between HD162215 (9.68) and HD162449 (9.81) so I estimated Mag 9.7. A small drop from the 15th.


    Next stop was V1405 Cass or as I like to call it “the (almost) eternal novae”
    Nova Cass appears to have faded slightly. It’s brightness is similar to HD220770 (7.82) and noticeably fainter than HD220819 (6.61). I estimated the mag at 7.6.


    I though I would try Jupiter as it had cleared the houses and fortunately the seeing had improved quite alot. It was still worse than the 15th but I could see some reasonable detail in moments of good seeing.


    3 of the Moons were visible and when I check Sky Safari it was Io, Europa and Ganymede. On closer inspection I realised Callisto was crossing the face of Jupiter and I decided to track how quickly I would be able to spot Callisto leaving the limb. Given the seeing I wasn’t sure how well this would go.
    Callisto 
    21.29.10sec. 1st detection
    21.32.46sec clear detection in moments of good seeing.
    21.36.00 sec continuously detectable but still appeared attached to the limb
    21.39.30sec. appeared fully resolved.


    The Moon was now visible between the houses. Using the 4mm (x100) I got fairly decent views of Gassendi. 


    My final stop was M57.
    Using the 25mm I could view both Gamma and Beta Lyrae (STFA 39) M57 and the wide double SHJ282AC appear as a yellow/blue pair. 
    Replicating this view should be possible in decent binoculars.
     

    Cheers

    Ian

    • Like 4

    Nova in Cas

    in Observing - Widefield, Special Events and Comets

    Posted

    On 16/09/2021 at 14:39, lunator said:

    Nova Cass is still quite bright. It looked reddish-orange to me.

    It was fainter than bright star HD220819 (6.61)
    Similar to HD220057 (6.94)
    Brighter than HD220770 (7.82) star and much brighter than SAO20610 (8.97)
    I estimated the magnitude to be about 7.
     

    It was my 2nd novae of the night :)

    cheers

    Ian

    Had a look again last night. It appeared to have faded a bit.

    It was fainter than bright star HD220819 (6.61) and HD220057 (6.94)
    Slightly Brighter than HD220770 (7.82) star and brighter than SAO20610 (8.97)
    I estimated the magnitude to be about 7.6

    The change over 48 hours was noticeable.

    Cheers

    Ian

    • Like 3

    Double Trouble

    in Observing - Discussion

    Posted

    STF1695 is listed in sky safari plus (Andriod) the double isn't shown in the map.

    I checked my observation of this pair.

    "A tightish uneven pair requiring a moderate magnification to split. A clean split was achieved with the 6mm (x100). The primary ia white and the secondary is yellow/orange"

    The scope I used was am ST120.

    Cheers

    Ian

    • Like 1

    Eruption of the Recurrent Nova RS Oph!

    in Observing - Widefield, Special Events and Comets

    Posted


    RS Ophiuchi
    Using  the 25mm (x16), first impression – no colour.
    Used the 12.5mm to darken the sky background a little more.
    It is quite faint now. 
    Fainter than HD162488 (7.98)
    Similar in brightness to HD162215 (9.68) & HD162369 (9.56)
    Brighter than HD162449 (9.81)
    I estimated the Magnitude at 9.6.

    I have enjoyed following this event. Although the OMC250 may have to be used more now :)

    cheers

    Ian 
     

    • Like 3

    Observing 15/09 - in surprisingly good seeing

    in Observing - Reports

    Posted

    Despite having a week off the weather has been pretty poor here in Bucks. There was some hope for clear skies and I was planning to get a quick look at RS Ophiuchi and the novae in Cassiopeia.


    It was looking good around 8.30pm so grabbed my ‘grab and  go’ set up of ST80 on the heavy duty photo tripod.                                             

    The 1st stop was the Moon low on South in between the houses.  Starting with the 25mm ortho giving x16and then using the 12.5mm(x32). The moon fitted comfortably in the field of view with clear detail. This gave me my first indication the seeing was good. I particularly liked the view of the Clavius crater. I  could see some of the interior craters so I pushed the magnification to x100 (4mm ortho) and the smaller craters were very clearly visible within clavius.


    RS Ophiuchi
    Dropped back  to the 25mm (x16), first impression – no colour.
    Used the 12.5mm to darken the sky background a little more.
    It is quite faint now. 
    Fainter than HD162488 (7.98)
    Similar in brightness to HD162215 (9.68) & HD162369 (9.56)
    Brighter than HD162449 (9.81)
    I estimated the Magnitude at 9.6.

    My 2nd Novae of the night was the novae in Cassiopeia. Just used the 25mm.
    Nova Cass is still quite bright. It looked reddish-orange to me.
    It was fainter than bright star HD220819 (6.61)
    Similar to HD220057 (6.94)
    Brighter than HD220770 (7.82) star and much brighter than SAO20610 (8.97)
    I estimated the magnitude to be about 7.

    Saturn had cleared the houses and with the conditions I decided to push the magnification to maximum available using the 4mm ortho. (x100). For the first time I spotted the band on the surface (this is easy in my large scopes) and I am certain I could see the Cassini division.  

    I moved onto Jupiter and very quickly decided to stay with the 4mm. I could clearly see multiple belts with details on their edges. Seeing all the belts and not just the equatorial ones was a very pleasant surprise. The 4 moons were strung out 2 either side. 
    This was the best view of Jupiter I had had in a small scope. 

    With the good seeing I decided to have a go at Pi Aqilae.
    It would be tricky in the ST80 with a separation of 1.4” and a delta M of 0.41
    The ST80 Raleigh criteria of 1.725” and a Dawes limit of 1.45”
    In my experience for bright close pairs even at the Dawes limit you can detect the companion if it is with 2 magnitudes of the primary. I was able to see an elongated star and when checked against WDs it was in the right quadrant. Overall i was quite pleased with the result.
     

    • Like 8

    Eruption of the Recurrent Nova RS Oph!

    in Observing - Widefield, Special Events and Comets

    Posted

    I got my OMC250 on this last night. The magnitude was still similar at around 8.2. 

    The red was much more apparent using the 250mm vs the 80mm. 

    Neil, based on the previous eruptions the average is about 15 years but varies between 9 & 26 years so there is a good chance to see it go again. The biggest issue could be if it happens when the Sun is in the same part of the sky and it gets missed.

    I am going to go out on a limb and say the next Outburst could be less than ten years.

    The previous outbursts are noted as 1898,1907,1933, 1945, 1958,1967,1985,2006,2021

    The gaps are 9,26,12,13,9,18,21,15. If you take the 1907,1933,1945,1958 you get 51 years. If you take 1967,1985,2006,2021 you get 54 years. It may be just co-incidence but I wonder if there is a third component in the system with ~50 year orbit having an effect.

    I might be completely and utterly wrong tho' :)

    Cheers

    Ian

    • Like 3

    Eruption of the Recurrent Nova RS Oph!

    in Observing - Widefield, Special Events and Comets

    Posted

    12 hours ago, robin_astro said:

    Interestingly the AAVSO data shows the visual observers are doing just fine 

    RS_Oph_photv_visual.thumb.png.c3279bfff3ecf47fe00c922da716025d.png

    I have been following RS Oph quite closely. It is the 1st variable I really paid attention too. From a visual perspective at 8th mag it is still bright enough to show colour even in a small scope. I have been using an ST80. It does show "flashes" of red when I am observing it but the change in colour does not seem to have changed the overall magnitude as far as it appears to me. 

    Cheers

    Ian

    • Like 1

    A quick 90mins session

    in Observing - Reports

    Posted

    I managed a very short session last night, the was a 45 min clear patch between the clouds.

    A quick check in on RS Oph. Still about mag 8.2 not major change but the redness is quite noticeable. I will miss RS when it is back to 11th-12th Mag. I have been reading the free papers submitted in it and it seems there has been quite a lot of discussion about it's nature and distance etc. I even looked into the Gaia data and the orbit would swamp the parallax signal so they don't have. a distance for RS.

    Next stop was Saturn. Titan was clearly visible and I thought I got a glimpse of the Cassini division at x100 (4mm ortho)

    It may just have been averted imagination :).

    Final port of call was Jupiter. It was only just clear of the house but seeing was good enough to see several cloud bans and the GRS. The best views were at x80 & x100. I could see 3 moons but it was not until I came in looked at Sky Safari I discovered Io and Europa were on 2" apart so I was looking at 2 moons but not realising this. The OMC might have been a better one to see this in.

    The clouds rolled in at this point. 

    As a PS Ethel joined in and I have now designated her my official hedgehog observing Companion :)

    Cheers

    Ian

    • Like 3

    A quick 90mins session

    in Observing - Reports

    Posted

    Last night was looking fairly promising and i wantd to check up on RS Oph. 

    I have my grab and go set up of ST80, photo tripod and ortho eyepieces.

    I put the scope in the middle of the garden to cool down a bit whilst trying to avoid the slugs and snails (they have had a very successful year this year, the pea plants less so...). 

    I placed my observing log and pencil case on the swing seat, I do love a bit of high-tech :)

    First stop RS Oph. My route to finding it is start at Rasalhague (Alpha Oph) and move down to 67/68/70 Oph. Go south from this triangle and you will find a fainter triangle of Zeta Ser/HR6686/6706. On the opposite of the triangle from Zeta Ser are the 3 stars HD162713/1562834 and YOph. RS Oph is in the same field of view.

     Rs Oph is fading but at a slower rate now. It has changed from a golden yellow to a more reddish-yellow. Around Mag 8. plenty of similar stars to compare it to. 

    Next planned stop were STF1814/1829 in Bootes went via Mizar and Alcor. Mizar were is neat pair of white stars just split at x16. 

    I was disturbed at this point by our semi-domesticated hedgehog 'Ethel' crashing through the undergrowth. I moved to see where she was and realised if I moved the scope I could see Saturn and Jupiter. I spent a good 30 mins viewing them. 

    The ST80 had started to dew up so I called it a night. 

    I will add reports in the appropriate section for the double and planets. 

    Cheers

    Ian

    • Like 10
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.