Layers in the Solar Chromosphere

Here is an interesting thought inspired by Pete Hill’s “solar array”.

If we observe the Sun in white light, we are seeing the photosphere.

If we observe the Sun in H-alpha light, we are seeing the chromosphere.

The chromosphere (literally, “sphere of color”) is the second of the three main layers in the Sun’s atmosphere and is roughly 3,000 to 5,000 kilometers deep.

If we therefore mix a white light with a Ha image in different proportions, are we seeing different layers as we go through the chromosphere?

By a fortuitous coincidence my Ha scope and the scope I use for white light imaging have the same focal length, and so produce the same sized images. So this mixing is quite easy to do.

Here is sunspot 2699 on 07/02/2018 together with the mixed sequence.

Observing Log entry 20/4/2018 @ 21:30-21/4/2018 @ 00:30

Damian gave me a call and I went around to his house last for probably the best galaxy observing session I have enter taken part in. This was largely facilitated by his amazing TEC 140mm telescope on Novohitch mount. The TEC is a highly corrected apochromatic refractor and something to die for, producing Takahashi quality images but with larger lens sizes (140mm vs 104mm in Damian’s Tak). The mount is perfectly engineered hand-crafted piece of kit and perfectly complements the TEC. It easily carries its weight. It is not motorised at the current size but does have push-to digital setting circles which repeatedly put the object of interest in the centre of the field of view. Damian’s iPad sits on a bracket on the side of the mount and shows exactly where the telescope is pointing using Sky Safar app. The combination means that, as an observer using this equipment, I felt as though I had that link to the sky as we moved the scope around – which is just not there with a GOTO mount such as my EQ6. Wonderful! Last night was a fitting tribute to the Novohitch’s maker, who sadly died very recently.

Then there were the galaxies. The sky was not perfectly clear and we were not in a dark sky site. Damian’s house is on the edge of Lichfield. However, in spite of this, we just couldn’t miss – any galaxy under magnitude 10 could not escape us! What I am not sure of is how much our increasing skills and experience as observers played a role in this – but what I am sure of is that I have never seen so many galaxies in such a short period of time!

We started in Virgo – 1, 2, ,3 ,4 ,5 galaxies – then to Leo, both triplets – 2 galaxies in first triplet, FOUR in second!! Several other galaxies in Leo, then to Ursa Major M106, M51 and even we could pick out M101 and see mottling within it (that one was VERY faint but we definitely saw it!!), then a whole list of galaxies across the Northern Sky including Whale Galaxy and a large range of others, then back to Virgo to pick up some more galaxies. I haven’t written a list down as last night I just wanted to enjoy myself but I will remember this night as one of the most amazing observing sessions of my life – even though the sky wasn’t perfect.

[Looking at Stellarium, I have identified some of the galaxies we saw:

In Virgo we observed Markarian’s chain including the eyes NGC 4435 and NGC 4438, M86, M84; also in Virgo M58 and M90, M85, and some close by NGC galaxies.

In the rear Leo triplet, M66 and M65 were observed but we did not see NGC 3638 (which is surprising as we saw fainter galaxies later on).

In the other Leo triplet, we could see M95 and M96 and two of NGC 3389, NGC 3384 and M105, which is strange because those latter three are all supposed to be less bright than magnitude 10, so I think that the extent to which a galaxy is condensed makes a big difference to our ability to observe it.

We also saw NGC 2903, NGC 3606 (we were on form by now!)

In Canes Venatici, we observed M94, then the Sunflower Galaxy M63, NGC 4449, M106, Whale Galaxy NGC 4631, and, in the general area, a number of others.

Finished with M13 and M92 globular clusters in Hercules.]

Andy

Algae superfood after two days in water

Ean Ean has bought for me a “superfood” based on Spirulina algae – apparently Kate Middleton eats it! It is sold as dry powder and I wondered if it was dead or alive. I put some in a cup of water for two days in the sun. In the photos below you can see algae cells – however lots of bacteria too which suggests that the algae are killed and the bacteria quickly take up residence with plenty of food available.

[You may also wish to view a following post where further work was done on this slide using COL, http://roslistonastronomy.uk/circular-oblique-lighting-col-on-microscopic-images-of-bacteria-and-algae]

Andy

Four algae cells showing cilia around edge from Hopwas Canal

Ean Ean and I collected the sample of water from Hopwas canal 19/4/2018 and today I viewed it in the Zeiss IM microscope using 40x objective. The picture below shows multiple cilia (hair-like structures) around edge of the cells which the cells use to move around. I have used Curves function in GIMP2 to enhance the image to demonstrate these cilia more effectively.

Andy

Ean Ean collecting sample from canal:

DSO hunting in Bootes – Canes Venatici – Coma Berenices 18-19/04/2018

A fine night at last! Haven’t been outside for quite a while with the trusty PD camera, so here are a few DSOs I imaged last Wednesday night. Apart from the obvious ones, NGC5466 is a small obscure globular cluster in Bootes not far from the better known M53. We have also got M100 in Coma Berenices, NGC4298 & NGC4302 in Coma Berenices, NGC 4618 & NGC4625 in Canes Venatici, NGC 4214 in Canes Venatici, NGC 5371 in Canes Venatici & C45 / NGC 5248 in Bootes,

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.