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Below are the 19 most recent journal entries recorded in fivemack's LiveJournal:

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Thursday, August 20th, 2015
7:13 pm
Scout's report from Sail 2015
I know several of my friends are coming over to Amsterdam for this; I've been to it today and might as well report.

First observation: the ship switches to Dutch time at about midnight, Dutch time is an hour ahead of UK time, and so you may be perturbed when the unsilenceable speaker in the cabin ceiling announces at a time you believe to be 5:30 that we will be landing in 90 minutes.

The event is behind the central station and thoroughly signposted from within the station.

The main area, with the tall ships you can visit, is the 'orange route'. This goes round two long sides and one short side of the old docks, it's a five-mile walk, and as far as I can tell at the end you have to retrace your footsteps five miles back to Amaterdam Central Station. Two of the more exciting attractions - the modern submarine Bruinvis and the current Dutch Navy flagship de Rutyers - are right at the far end. The submarine stops accepting visitors at 4pm, the flagship at 4:30; today I missed both.

You might be better off taking a tour of the ships from the water: you can buy a timed e-ticket from www.ntk.nl under 'sail', it's €20 for adults, €10 for children, €0 for small children. This tour puts you in the procession of ships that go round the dock: if you're walking, the walk goes clockwise and the procession goes clockwise and so often you'll keep up with the same processing boat for some time.

The first couple of visitable ships have long queues, the queues are much shorter for later ones. I would recommend the Ecuadorian ship Guayas, the enormous Staatsraad Lemkuh, and (on the second half of the circuit) the small but perfectly-formed Australian Young Endeavour, the unpronounceable Polish Dar Młodzieży, and right at the end the French Belem which used to be the private yacht of the Duke of Westminster and later of the Guinness dynasty. The Chilean Esmerelada is so near the start as to have a long queue, and has a slightly unreconstructed tone to it with "Victory or Death" and "la razon o la fuerza" mottos everywhere.

Bring loads of water: if you can, bring a picnic. There are loads of food and drink stalls, but the standard pricing is €2.50 for a small drink.
Saturday, May 30th, 2015
7:22 pm
Messier 104
This is another spiral galaxy, just short of edge-on to us, with a very prettily-placed band of dust in the plane of the galaxy - you can see that the nucleus is on the top side.

Tends to be called the Sombrero galaxy. Combination (using software I've just written) of five 90-second exposures; the purple colour cast is an artefact of pulling the levels up to show the faintest stars.

6:07 pm
Messier 82
This is a starburst galaxy in Ursa Major; it's a spiral galaxy, viewed edge-on, with an enormous cloud of dust in front of it.

Sum of two 90-second exposures at ISO 1600 with 2250mm-focal-length f/4.5 giant telescope; I took five, but for three of them the wind was blowing hard enough to disrupt the telescope guiding and distort the bright stars into unusably strange shapes.

The apparently odd-shaped star in the top left is HD85161, which does have a companion star in the position that appears on this picture. It's surprisingly hard to find on-line star catalogues comprehensive enough to tell me how bright the faintest stars appearing in this picture are; ones which are over-exposed to the point of saturating at the centre are around magnitude eleven (IE a hundred times too faint to be seen with the naked eye), which makes sense since the big telescope collects about ten thousand times as much light as the naked eye does.

Monday, May 25th, 2015
7:16 pm
In the realm of the nebulae
This is the twenty-inch Newtonian reflector at the Centre for Observational Astronomy in the Algarve, where I have just spent five nights


And this is roughly what you get if you point it into the middle of the Virgo galaxy cluster, attach my nice camera, leave the shutter open for 90 seconds at ISO1600, and tidy up a bit in Photoshop afterwards.


I think there are six and a half galaxies visible here; M84 and M86 are the big ellipticals top and bottom respectively, NGC4387 is the little one in the middle, NGC4388 is the interestingly-shaped one on the right, NGC4402 is the dim fuzzy one on the bottom left, IC3303 is the teeny faint one you get to if you start at M86, go to 4387 and keep going, NGC4413 is the half-cut-off one right at the bottom on the right. I'm not at all sure what the name of the tiny companion galaxy about a centimetre at clock-7:30 from M86 is.
Saturday, May 9th, 2015
9:32 pm
Scale errors
The total amount Race For Life has ever raised would pay the NHS's drugs bill for a fortnight.

The total amount Comic Relief has raised in thirty years would pay Britain's housing benefit for three weeks.

The total amount ever raised by the Disaster Emergency Committee is about a month's budget for the DFID.

Those are the kind of statistics it's worth having in mind when listening to talk of the Big Society; replacing single specialised pieces of taxpayer funding would require initiatives as big as the biggest ones we have. There's not the slightest hope of reliably getting three times as much donated annually to the task of funding the library service as was donated to the relief efforts for the 2004 tsunami, and that's what libraries in the UK cost.
Monday, April 6th, 2015
9:26 pm
Space station!

This is in all absolute senses a series of awful pictures; on the other hand, it is a series of pictures, from my back garden with my birding-lens, of a moving object about the size of a 747 located two hundred miles away.

Holding a 3kg camera-and-lens combination at arm's length for five minutes is an excellent exercise for the bicep; focussing the blasted thing on the other hand, even with the stars as convenient point sources, is an exercise in frustration.
Wednesday, March 11th, 2015
8:14 am
Sol maculatus

Same lens as the moon picture; Orion Optics full-aperture solar filter. Pointing a very long lens hand-held at the sun while holding the filter on with the other hand is not as completely trivial as you would expect - you move until the shadow is minimal, and then squint a lot.
Wednesday, March 4th, 2015
11:06 pm
The moon, tonight, with my New Absurd Lens

It's near-enough full moon, so the rays from the craters are particularly visible; click on the image to get a bigger version with labels. The moon looks about as big as a shelduck two hundred feet away, so I'm expecting to get some quite nice pictures when I have spare time on a sunny weekend and go over to Fen Drayton lakes.
Wednesday, February 25th, 2015
11:22 am
Classics question too broad for Google to easily answer
What are the best surviving Roman sites in Asia Minor?

I've seen Ephesus and Aspendos suggested (along with an indication that there is at least one interesting city in Tunisia if I want to go to that end of the empire instead: Leptis Magna is the great site in that part of the world but it seems likely to be quite a while before contemporary geopolitics clear up enough for a visit); aside from the amazing cistern I was surprised how little Constantinople was left in Istanbul.
Sunday, February 22nd, 2015
9:03 pm
Ludicrously detailed Neapolitan nativity


This is a Nativity scene displayed in the Palace Chapel of the Royal Palace at Naples. The Christ-child can be seen down and to the left of the yellow angel, or up and to the right of the large group of Moorish musicians (wearing scarlet, just to the right of the leftmost camel), barely visible above a sheep.

Click to zoom in; the image spans nicely across two HD monitors, or you can pan around it on a normal computer.
8:32 pm
Among the worse-rendered dolphins of the world

From the Palazzo Real in Naples
Monday, February 16th, 2015
5:14 pm
5:13 pm
5:13 pm
An orchestra of cupids serenades the Christ child

I think there is real music on the book: though I'm not sure the average mother of a newborn would really appreciate that large a trumpet.
Sunday, January 25th, 2015
11:16 am
Suppose you have taken a photo with some stars in it, and you can't remember exactly what you were trying to point at at the time. For example, this one


I've had to mangle it a bit in Photoshop to make it more obvious that it's a field full of stars.

If you go to http://nova.astrometry.net and click 'upload' and send them the full-size, unmangled-in-Photoshop version of the picture (available here) then after forty seconds of processing in the cloud you get back

Center (RA, Dec):(96.103, 34.407)
Center (RA, hms):06h 24m 24.652s
Center (Dec, dms):+34° 24' 25.689"
Size:43.5 x 28.9 deg
Radius:26.107 deg
Pixel scale:36.5 arcsec/pixel
Orientation:Up is 129 degrees E of N

and a version of the image with the stars and constellations marked on it:

Thursday, January 22nd, 2015
9:32 pm
The mounting turns out to be the important thing
With a clever bit of mechanism to keep it pointed in the right direction, you can get quite reasonable pictures of the stars with a moderately fancy camera and lens from a desolate fen a mile outside Horningsea:



Thursday, January 1st, 2015
5:37 pm
It's that pie chart again

Very much like last year; I spent less on computers (it is not entirely unreasonable to have a personal belief that computers should not be bought in even-numbered years, and neither Intel nor the ARM ecosystem managed to release anything terribly tempting in 2014).

I've now been doing this for a decade, and it hasn't changed very fundamentally since then:

Saturday, December 20th, 2014
5:08 pm
May be an impossibly teleological question
Why is it that volcanic ash makes good fertiliser?

It contains minerals pulled up from the upper mantle and pulverised into conveniently absorbable powder; but is it purely a coincidence that it tends not to contain chromium, cadmium, arsenic and heavy-metal fluorides (fluorides mentioned specifically because volcanic steam does contain non-negligible HF)?

I suppose the volcanoes that erupt great clouds of sulphur tend to be known as sulphur mines, and obviously people won't farm next to volcanoes whose outpourings make plants wither, but it seems unaccountably convenient that they so often work.
Tuesday, December 16th, 2014
1:54 pm

Who will join the Euro first?

The UK
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