Mike Harlow

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  • in reply to: Display of NLC on 2016 July 6 #577428
    Mike Harlow
    Participant

    NLC display also well seen from Ipswich.  I took a few shots with a hand held camera from an upstairs window!

    This one was taken at approx. 3.45BST

    in reply to: chi Cygni 2015 #576933
    Mike Harlow
    Participant

    Hi Andy,

    Thanks for your comments.  I’m learning Visual Spec as we speak! It’s good because it does the non-linear calibration of wavelength which is required when working with a prism.

    Not sure I can make the Spectroscopy workshop in October…but hopefully there will be a DVD of the event…???

    All the best,  Mike

    in reply to: chi Cygni 2015 #576931
    Mike Harlow
    Participant

    I thought it would be interesting to compare spectra of chi Cygni and mu cephei as they are both famous red stars.

    I used the on loan BAA objective prism on my 12inch F/6.8 astrograph stopped to 4 inches and an un-modified Canon 550 DSLR.  Despite the limited spectral range of the DSLR the spectra are clearly quite different. Comparison spectra are on the Orwell Astronomical Society forum:

    http://forum.oasi.org.uk/download/file.php?id=393&mode=view

    Only a quick look at this stage, I hope to get a CCD spectrum with the same set up in the next few weeks.

    I also observed visually and chi Cygni was clearly visible to the naked eye.  And through my 4 inch F/5 guide scope mu Cephei appeared to be redder than chi Cygni. 

    Mike.

    in reply to: Variable Nebula Update #576586
    Mike Harlow
    Participant

    My latest image of this southern variable nebula came through on Friday.  When I compared it to one taken just 23 days earlier it was clear that there had been some small changes in the nebula.  I re-processed both sets of images in the same way and then compared them side-by-side.  The negative images below show the changes.

    The central region has brightened but the small knots of nebulosity extending eastwards have faded. A bigger version is on the Orwell AS web forum: http://forum.oasi.org.uk/viewtopic.php?f=6&t=43

    This object is certainly well worth observing regularly to monitor its long term behaviour.

    Mike.

    in reply to: Variable Nebula Update #576585
    Mike Harlow
    Participant

    My latest image of MrG’s nebula shows that the eastern arm that was so prominent in the second half of 2013 is now fading.  The nebula now has an appearance similar to that in the early part of last year.

    Full sized image in the usual place…http://forum.oasi.org.uk/viewtopic.php?f=6&t=43&start=10 on the Orwell AS web forum.

    Why not get out and observe this interesting little nebula?  It is circumpolar from the UK at RA 20h 46m +67d 58m and associated with the star PV Cephei.  But be warned…it is quite small and faint.

    Mike.

     
    in reply to: Variable Nebula Update #576577
    Mike Harlow
    Participant

    My latest monthly image of MrG’s nebula is attached.  The nebula continues in a stable state having had more or less the same appearance for the past 18 months.  But it could change at any time so is well worth monitoring.  The field of view of this image is ~ 10 x 10 arc minutes.

    The full size image and all my previous attempts are on the Orwell Astronomical Society web page: http://forum.oasi.org.uk/viewforum.php?f=6

    Mike.

     

    in reply to: Neptune and Triton #576571
    Mike Harlow
    Participant

    Only one more image so far as the weather in Australia hasn’t been very good recently!  This one is at the same scale, has the same orientation and the field star is also the same showing the motion of the planet.  Triton rotates anti-clockwise in this view and has completed about 2/3 of an orbit.

    More to follow when the weather improves!

    Mike.

     

Viewing 7 posts - 41 through 47 (of 47 total)