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Have seen some C11 size heaters for £50 but it didnt quote the power…
Useful webpage! Followed a link on that site and have asked them for a quote on the co-mounting bars.
Apparently, the light curve (if a uniform albedo is assumed) implies a length to width ratio of 6:1 or more which is pretty phenomenal. Theres also a spectral response similar to a Jovian Trojan but dissimilar to a KBO. How does that form?
Its name is something or other in Hawaiian. Cannot understand how an interstellar interloper plunging through the solar system and boasting a large aspect ratio has not ended up being called Rama – as fans of AC Clarke would know.
Fascinating object. Shame it was at mag 23. But there are, allegedly, lots more around.
Love the fold in roof support.
How much does the roof weigh? Is it difficult to get back into place at the end of the night?
As i recall, the rainfall maps show Norfolk to be pretty dry and you’re a good way away from any big hills, so does anyone living out that way care to comment on the amount of fog and clear nights?
In Wiltshire, where I am, there do seem to be a few foggy days in the autumn and winter.
Thanks. Thought that might be the case.
As you say, you could do some smoothing but that reduces the temporal resolution. Alternatively, there is processing you could do to assess interline scaling factors, but you would need to do some calibration runs at exactly the same camera settings – perhaps using a non-tumbling satellite as a reference.
Meteors are not my area of study, but is this an interlaced camera?
The saw pattern on the light curves was interesting.
Two colour and one monochrome image added. There must be lots of BAA members with better pictures though…. Nik?
At a conference I am at, some observers from a small university observatory in the Virgin Islands reported visual counterpart observations from a system that is in the 0.5m league – though their sky is rarely below 20.5mag and despite the fact a cat 5 hurricane was about to hit.
They – and several other teams – caught it reasonably quickly via the alert system.
Heres one that might help…
https://www.metoffice.gov.uk/binaries/content/gallery/mohippo/images/migrated-image/2/avgrain1.jpg
Not cloud as such, but associated…
The problem boils down to what do you image/draw/observe.
If its planets then almost anywhere away from a town is good.
If deep sky then choose the dark area on the Philips dark sky map. In addition, you need to start looking at cloud cover figures – I found some on line a year or so ago (do not recall where). I recall Norfolk way being good and having lower rainfall than most the country, but I’m not sure how it did for fog.
We were surprised how much cloud the Welsh borders got when we lived there. Its within the cloud shadow of the Welsh Mountains. Beautiful place to live, but you can get long runs of no blue sky.
Personally I would rather have a couple of really dark clear nights a month than four mediocre one.
There is a great feeling of satisfaction when closing down for the night as the dawn starts to brighten the sky. Though its often accompanied by thoughts like “Arrgh. I’ve got to be at work in 4 hours.”.
In that case, could the ship owners claim salvage rights on the Harrier? That must have been a fair amount.
My copy of Covington’s book suggests that at f/11 and 400ASA/ISO, an exposure of about 1/250th is about right for prominences and 1/15th for corona. Well worth bracketing from 1/1000th down, but how are you mounting the camera? Driven? Undriven. Fixed tripod?
Handheld and without autofocus and stabilisation, the suggested minimum exposure for a half decent photographer in the film days was 2/FL where FL is focal length in mms or, in this case, 1/200th of a second. But a tripod and cable release should improve on that by nearly a factor of 10 I think.
For 1999 I went from 1/1000th to 1/20that 400ASA. Pics were a little soft, but usable.
But really we need an expert like Nick James who has seen total eclipses more times than most. 🙂
