Mandy D

We weren't a million miles from Dieppe, but for the life of me I cannot remember the name of the place. We went into Dieppe later.

On this day, 23 years ago, we had perfectly clear skies with not a cloud in sight in a village somewhere in northern France. Then, just as totality was approaching a small cloud began to materialise out of nowhere next to the Sun. There was no chance of moving to a new site, this close to totality, so we had to stay put. The cloud covered the Sun moments before the total phase began and started dissolving immediately it was over! It did still go fairly dark though! You win some, you lose some!

I thought I would try my Nikon 135 mm f/2 lens on Arcturus and compare the results with the 200P. Obviously, the diffraction pattern is very different at f/8 with this lens and it has brought out the colour of the star.

Absolutely beautiful! 4.5 hours very well spent on a truly gorgeous nebula. It looks very much 3D in the central regions.

Thank you! I think it has proved my 200P quite nicely.

This is just a star field that I was using last night to focus the telescope prior to imaging the Moon, but I got some nice diffraction spikes on Arcturus, courtesy of my Skywatcher 200P.

Definitely conversation! Momentous? Not so sure! 😂

There has to be a safety margin applied to all such things and it's probably at least a factor of two if it's been properly engineered. If it's made in China, who knows? A 5% overload on the chair is likely to be perfectly OK. The chair also has to handle dynamic situations such as you dropping yourself into it when you first sit down and this is the time it is most likely to collapse. Lower yourself in gently and it will probably be fine. The general rule is that you do not overload things beyond the specification, but in real life many people do, even if inadvertently. You'll have to make your own mind up on this, as it is your safety which is at risk.

I think that is going to come down to experimentation. We always had an ammeter in circuit so once you know what works it is easy to repeat. I would not expect aluminium wire to glow before producing a vapour in vacuum. It may start to sag, though. One other thought that has occurred to me is that aluminium oxidises in air to form a thin layer of Al2O3. You won't want any oxygen in there when it vapourises, so will need to clean the wire immediately prior to use and not touch it with your hands. Lots to think about.

Yes, I remember those days. I also remember a huge spot that was naked eye visible on the setting Sun back in the nineties.

Thanks. I was on my own and had to carry everything about 50 metres from home and forgot some of it and didn't want to leave the telescope on it's own to go fetch the barlow and D3200. When I am able to drive again (eye injury) I will throw it all in the Land Rover and set up properly and have another go.

I dragged the Skywatcher 200P out onto the street last night and set up under the trees away from the uber-bright LED street lamps as Saturn was just coming into view above the roof line on the opposite side of the road. I'd forgotten to bring the finderscope with me, so it took ages to find Saturn in the main scope, then when I had it in the viewfinder of the D800 it was so tiny I couldn't see to focus, but at least I got a recognisable Saturn in my photo. I thought I might try a bit more magnification on it, so I dug my barlow out of the bag and stuck it on the 1.25" Nikon nosepiece before finding out that I'd not brought the reducer for it to fit the 2" focusser! After messing around for ages, I noticed that Jupiter had popped up over the roofline, so I turned the scope in that direction and found it quicker than I expected without a finder! I couldn't see any detail or any of the moons, so took a few photos with longer exposure and higher ISO until the moons showed up. Nothing great on either planet, but here are my best photos of the evening.

The general trend is that the Earth's rotation will slow down, but it is influenced by so many external factors, that sometimes it can speed up. For example, Jupiter has enough mass to perturb the orbits of the other planets.

Obviously, as others have said, more cooling is required for your pass transistor (TIP35). You have 5.4 volts across that transistor and up to 1.5 amps collector current. By my reckoning, that is a dissipation of 8.1 watts. For a comfortable rise of 50°C, that requires a heatsink rating of 6K/W. You note that adding more capacitance to the input and/or output does not improve things. If you want to continue with this design of converter, I would suggest proper input and output LC filters, rather than just capacitance. So, a choke (inductor) in between pin 1 of J1 and the filter capacitors and similar on the output side will improve your situation.

Yes, that looks like it might well work.

Hang on ... Politicians! They'll at least find a way to tax it based on angular momentum, if they knew what that was. Let's not tell them, huh? 🤣

Apparently, after having had to add leap seconds to the calendar, the Earth's rotation is speeding up. So, we will probably have to take a second off at some point. Earth's record shortest day (fastest rotation) was on 29 June 2022 and was shorter by 1.59 milliseconds. So, after just two years of spinning at that rate we would be ready to subtract a whole second! Are we ready for that momentous occasion? 😂 https://earthsky.org/earth/earth-shortest-day-record-atomic-clock-leap-second/?utm_source=EarthSky+News&utm_campaign=f7acfc0501-EMAIL_CAMPAIGN_2018_02_02_COPY_01&utm_medium=email&utm_term=0_c643945d79-f7acfc0501-395658673&mc_cid=f7acfc0501&mc_eid=943d2b0a6a

I had to give it a go after you put all the effort into collecting those photons, as there is no way I could achieve that at present. And, you are right: A truly remarkable piece of the sky. ✨

Awesome! I zoomed right in on your image at 200% in GIMP and counted about 10 x 10 stars in each 50 x 50 pixel sample I tried, which I reckon gives something like 1.4 million stars in the image. But, I could be way off! Whatever the count, it is very nice.

Not a great image after all the great photos some of you got of the prom, yesterday, but by the time I got home and set up it was all over or I just failed to capture it. There are a couple of small groups of sunspots, but nothing terribly exciting. D800, 600 mm lens and solar filter.

It's a whisker of hot glue from the blob used to secure the large capacitor.

Arrrgh! My scopes are at home and the skies are cloudy.

Clearly, the carriers are useless and the compensation offered is laughable. I will not post any anecdotal stories of my own experiences with carriers, but there have been many. I feel for anyone who is offered €3.50 / kg for high value astro or photography kit; it is beyond an insult. I've paid for a 1000 kg pallet delivery before, only to find out that when they totally destroy everything, including the pallet, the payout is based on the weight of the scrap they scrape up off the floor, excluding packing materials, to which they assign zero value and you don't even get to keep the salvage which may be worth more to you than their payout. Here is what to do: Take out separate insurance with an idependent insurer. I am not advertising or recommending the services offered in the link below, it is simply one found by performing a search on Google: https://www.secursus.com/en-gb/ Have a look at what is available by doing your own search and decide for yourselves if this suits you.

Have you thought about having the threads helicoiled? This will give you a steel thread for your bolt to screw into, instead of keep stressing the aluminium every time you screw the bolts in.

Low quality metal parts are becoming more of a problem. I saw a 3 jaw lathe chuck advertised on Amazon, "made from high quality zinc alloy"! You honestly could not make this stuff up!