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Hi Lars,
The Minor Planet Center will be able to provide an Ephemeris via web page https://minorplanetcenter.net/iau/MPEph/MPEph.html. You will need to use C/1980 Y2 for the comet name and then add the date you want such as the discovery date of 19801225 and then an ephemeris will be created such as that below for a geocentric observer. You can change the observer location by adding an Observatory Code (e.g. 000 for Greenwich which will be sufficient for the UK).
Hi JR,
Firstly I assume you have successfully using the PST visually with an eyepiece to see the chromosphere – although solar activity has reduced recently there is a reasonable group at the moment which even produced a flare this afternoon. So if all is OK using the PST visually this indicates that you have correctly wavelength tuned the telescope. If it off-band you will just see a featureless disk a bit like in your image.
The difficult part of using a DSLR or indeed any other type of camera with a PST is obtaining focus. This requires using a Barlow lens (which you appear to be using) or an eyepiece lens to bring the focal plane of the DSLR closer to the PST eyepiece holder. I suggest you perform a Google search using ‘PST and DSLR’ without the quotes. There you will find videos and other information (e.g. https://www.youtube.com/watch?v=RYDzdYkVbGM). Note there is no need to modify the PST eyepiece holder itself.
Peter
Hi Denis,
If you go to the ‘About Us’ tab on the BAA home page and then select ‘Who’s who’ you will find a list of trustees, the council and section directors. As I was at the AGM last October, the number of votes for each candidate for the current council was given – I assume this part of the meeting has been included in the video of the meeting (but I’ve not checked myself’.
Best wishes,
Peter
Hi David,
I suggest just emailing the excel file to Lyn. She will extract your observations and use them for the monthly solar section newsletter.
Peter
Hi David,
The blue cells in the Solar Section white light reporting form are for the total number of groups (gn, gs, g), sunspots (fn, fs, f) or sunspot number R seen during a month. Gn, Gs and G are the number of active area/groups seen in the northern hemisphere, southern hemisphere and the whole solar disk on each observing day respectively. If you only count the number of groups for the whole disk, then please leave the gn, gs, fn, fs columns blank. R is 10*g + f.
The MDF values are the mean daily frequency values for gn, gs, g – i.e. these are the average number of groups during the month. Finally R in cell J43 is the average R value for the month.
Once you have completed your form, please send to Lyn Smith (solar@britastro.org).
Peter
The attached image shows NGC 6946 acquired on 2017 May 14 at 11:07 UT using iTelescope T24 in California (the average of 3 x 120s exposures) and a comparison DSS image (using Aladin v9.0). The cross and red circle shows the new object (not visible in the DSS image). A larger version of the image is attached.
Astrometrica gives a magnitude of V=13.1 and position RA 20 34 44.24, Dec +60 11 36.1 (J2000) for the new object.
