Dob on Skye.

Awoke at 2am, pulled open the curtains and I could see was stars ! Got out and set up. Looking around the sky was the darkest one that I’ve seen.

Could hardly make out Leo for stars, under Leo the sparkling web of the Coma Berenices. Using the Pocket Sky Atlas and Telrad, it was easy to star hop to galaxies.

I love the Canes Venatici galaxies, “The Whale”(NGC 4631) crossed the fov with the “Hockey stick”( NGC 4656/57) just out of view. Had superb views of the old favourites, M94, M106, NGC 4244,4214,4111,4490 with 4485,4449 and 5005. M51 was gorgeous with structure and the “bridge ” to NGC 5195.

Then onto Leo and a happy looking Triplet . Up to Bode’s , both stunningly bright and detailed. M109 and M97 showed up as did many galaxies in a sweep of the UMa and Virgo bowls. A keen Easterly sprung up and it was a bit nippy to draw. To the east , a long torn and very bright Milky Way passed through Cassiopeia. A lovely view of “Caroline’s Rose” caught in a dense starfield. I kept looking around , by eye the view was like a deep blue planetarium gone black ! The globular clusters M13, M53 and M3 ( halfway from Arcturus to Cor Caroli) were like sparkling diamonds on a black velour sofa ( reminds self to be careful with the vacuum ).

Skye is an odd place. Been up every year since 1971 and I can’t remember masses of clear sky. The landscape and Dragon in law and family make up for it. There are accessible places away from any light pollution that will just amaze .

A fantastically dark site under clear skies ! Nick.

Solar Array

Today allowed me to finally get my Solar array set up. After several attempts at balancing and positioning all the components and making modifications I was able to set up all 3 scopes in a balanced configuration.

Then using the Kendrick Solar finder on the central scope (Evostar 120) and setting the tracking to solar rate I then adjusted the alignment of the ST 102 and the PST, so that all 3 scopes showed full disk of sun in centre of field of view.

The idea is that:

the central scope will give white light images of the sun using a Herschel wedge with an ND3 filter.

the smaller ST102 refractor will give CaK images using a Herschel wedge without any filter and imaged with DMK41 mono ccd camera with Baader Calcium K filter fitted.

the PST will give H alpha images.

Today I was only using set up visually , to align scopes, so I used filtered Herschel wedge in the Evostar 120, a baader Solar film on front of ST 102 and the PST was used as normal. There were no sunspots visible and in H alpha a noticeable prominence at 4/5 o-clock position as registered by Roger this morning, no other prominences visible, nor was there much surface detail. No CaK detail as was not using camera, the sun was very variable , but there were enough bright spells this afternoon between 2 and 4pm to allow the alignment of all three scopes.

The mount was constructed with a piece of 10mm thick Aluminium bar 10cm wide and 35 cm long attached to upper side of lower vixen bar via two M6 bolts.

Two vixen bars were then attached to upper surface of Aluminium bar via M6 bolts, two sets of ADM mounting rings of suitable size were then clamped onto these vixen bars.

(ADM rings and vixen bars from First Light Optics.)

By adjusting screws in Rings I was able to align both scopes to get full disk in centre field of view, to remove scopes the top adjusting screw only in each ring is taken out, so when  scopes placed back in , tightening this screw only should put them back in aligned position, all bar a slight tweak.

To ensure the system was balanced about the axis running along the length of the Evostar, extra masses were added under the PST, these were attached via an M10 bolt with head removed and centre tapped with M6 thread, then attached to vixen bar with M6 screw head bolt through Vixen bar and M10 bolt to hold masses in place., this can be seen on photo below with scopes removed from rings.

By experiment on table top , approx. 1.5Kg was required on PST side to balance rig, brought 4 small masses from Astro Buy & sell, and drilled out centres to fit bolt. All we want now are some clear skies and sunspots!!

Thanks to Lee for advice on design and initial drilling and tapping of holes / threads.


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Attempts at dark field microscopy using x50 infinity-corrected objective with diaphragm

I still can’t seem to get dark field to work well!

Photos below using infinity-corrected 50x objective with iris diaphragm, curves adjusted in GIMP2.

Andy

Algae from my pot pond 12/4/2018:

Volvox on commercial slide viewed by myself today using same setup as above:

 

Visit to Herschel Museum in Bath

Ean Ean, Rhys and Hannah and I visited the Herschel Astronomy in Bath on the way back from a weekend trip to Wells. The Herschel Museum of Astronomy at 19 New King Street, Bath, England, is located in a preserved town house that was formerly the home of William Herschel and his sister Caroline. Its patron is Queen’s Brian May and the introductory video is narrated by Patrick Moore. It was from this house, using a telescope of his own design that William discovered the planet Uranus in 1781, and below are some pictures from the garden from which this observation was made. The photos are from our visit today.

The objects in the pictures below are in some cases the Herschels’ own or those of people close to them. Other aspects of the house are re-creations to give idea of what life was like when the Herschels lived there, including items from the same era.

Andy, Ean Ean, Rhys and Hannah

 

Stoney Littleton Long Barrow

Ean Ean, Rhys, Hannah and I visited the Stoney Littleton Long Barrow, on our way to visit the Herschel Astronomy Museum (see next post for our visit to that museum). A long barrow is a prehistoric monument dating to the early Neolithic period. They are rectangular or trapezoidal tumuli or earth mounds traditionally interpreted as collective tombs. The Stoney Littleton Long Barrow (also known as Bath Tumulus and the Wellow Tumulus) is a Neolithic chambered tomb with multiple burial chambers, located near the village of Wellow, Somerset. It is an example of the Severn-Cotswold tomb. The barrow is about 30 metres (98 ft) in length and 15 metres (49 ft) wide at the south-east end, it stands nearly 3 metres (10 ft) high. Internally it consists of a 12.8 metres (42 ft) long gallery with three pairs of side chambers and an end chamber. There is a fossil ammonite decorating the left-hand door jamb. The site was excavated by John Skinner in 1816-17 who gained the entry through a hole originally made about 1760. The excavation revealed the bones (some burned) of several individuals (https://www.heritagedaily.com/2017/11/seven-must-see-long-barrows-in-england/100889).

A south-east north-west orientation is very common for Mendip barrows (http://www.ubss.org.uk/resources/proceedings/vol24/UBSS_Proc_24_3_187-206.pdf). A discussion of possible Stoney Littleton Long Barrow Winter Solstice Alignment can be found at https://www.silentearth.org/stoney-littleton-long-barrow-winter-solstice-alignment/

Andy, Ean Ean, Rhys and Hannah