Archive | November 2011

UK counties, php array

Whilst making an update to the FAS Membership and Renewal System (MARS) I decided to add a drop down box for the list of counties, so that we can force people to pick one that is up-to-date… anyway, I created a php array of these and thought it might be handy for someone so they could just copy and paste it:

$listcounties = array(“Avon”,”Bedfordshire”,”Berkshire”,”Buckinghamshire”, “Cambridgeshire”,”Cheshire”, “Cleveland”, “Cornwall”, “Cumbria”, “Derbyshire”, “Devon”, “Dorset”, “Durham”, “East Sussex”, “Essex”, “Gloucestershire”, “Hampshire”, “Herefordshire”, “Hertfordshire”, “Isle of Wight”, “Kent”, “Lancashire”, “Leicestershire”, “Lincolnshire”, “London”, “Merseyside”, “Middlesex”, “Norfolk”, “Northamptonshire”, “Northumberland”, “North Humberside”, “North Yorkshire”, “Nottinghamshire”, “Oxfordshire”, “Rutland”, “Shropshire”, “Somerset”, “South Humberside”, “South Yorkshire”, “Staffordshire”, “Suffolk”, “Surrey”, “Tyne and Wear”, “Warwickshire”, “West Midlands”, “West Sussex”, “West Yorkshire”, “Wiltshire”, “Worcestershire”, “Clwyd”, “Dyfed”, “Gwent”, “Gwynedd”, “Mid Glamorgan”, “Powys”, “South Glamorgan”, “West Glamorgan”, “Aberdeenshire”, “Angus”, “Argyll”, “Ayrshire”, “Banffshire”, “Berwickshire”, “Bute”, “Caithness”, “Clackmannanshire”, “Dumfriesshire”, “Dunbartonshire”, “East Lothian”, “Fife”, “Inverness-shire”, “Kincardineshire”, “Kinross-shire”, “Kirkcudbrightshire”, “Lanarkshire”, “Midlothian”, “Moray”, “Nairnshire”, “Orkney”, “Peeblesshire”, “Perthshire”, “Renfrewshire”, “Ross-shire”, “Roxburghshire”, “Selkirkshire”, “Shetland”, “Stirlingshire”, “Sutherland”, “West Lothian”,”Wigtownshire”,”Antrim”,”Armagh”,”Down”,”Fermanagh”,”Londonderry”,”Tyrone”);

M76 – The Little Dumbell

A bit faint but you can just make out M76 – The Little Dumbell with the Bradford Robotic Telescope:
M76 with the BRT

Observing last night

We had a great night observing out at Wast Hills last night. It was really good fun, even if the cloud did come out and beat us in the end. I’ll post a few of the photographs with more discussion later but for now I wanted to share two of my favourite images from last night. One was us capturing Jupiter with a 0.0001s exposure in the U band and imaging the cloud belts – that’s a first for myself:
Jupiter clouds
I also took my camera along last night, though alas I had my tripod but forgot the crucial bit that links my camera to it – oh well I still managed to get a few decent shots without the camera shake, such as:
Wast Hills and Orion
The observatory with Orion rising in the background. As I say I’ll post more later but if you are interested the full set of photos from last night can be found over on flickr.

Jupiter with an OIII filter

I occasionally use the Bradford Robotic Telescope for remote imaging… here is an image of Jupiter’s cloud belts with an OIII filter:
Jupiter cloud belts
and scaling this logarithmically gives the Galilean moons too:
Jupiter and Moons

Probing magnetic fields with GALFACTS

My conference proceedings for ADASS XXI have been published on arxiv. These are a short summary of the rotation measure synthesis we have been doing as part of the GALFACTS project:
“GALFACTS is a large-area spectro-polarimetric survey on the Arecibo Radio telescope. It uses the seven-beam focal plane feed array receiver system (ALFA) to carry out an imaging survey project of the 12,700 square degrees of sky visible from Arecibo at 1.4 GHz with 8192 spectral channels over a bandwidth of 300 MHz sampled at 1 millisecond. The aggregate data rate is 875 MB/s. GALFACTS observations will create full-Stokes image cubes at an angular resolution of 3.5′ with a band-averaged sensitivity of 90uJy, allowing sensitive imaging of polarized radiation and Faraday Rotation Measure from both diffuse emission and extragalactic sources. GALFACTS is a scientific pathfinder to the SKA in the area of cosmic magnetism. Key to magnetism science with the SKA is the technique of RM synthesis. The technique of RM synthesis is introduced and we discuss practical aspects of RM synthesis including efficient computational techniques and detection thresholds in the resulting Faraday spectrum. We illustrate the use of the technique by presenting the current development of the RM synthesis pipeline for GALFACTS and present early results.”
There was room for our first RM map (a moment map collapsing all the channels) in the paper:
Rotation Measure Synthesis

Slovenia: Lake Bled

Whilst we were in [Croatia] we took a short trip over the border into Slovenia to go and visit the glacial Lake Bled. So this is part 4 of our visits while in Croatia. The lake is surrounded by mountains and forests and is very picturesque. The lake surrounds Bled Island which is the the only natural island in Slovenia – its actually a short journey across water to the island.. well short when someone else is doing the work.
Lake Bled
As you can see in the above image there is a Church on the island. This is the Pilgrimage Church of the Assumption of Mary which has a 52-metre tower with a nice clock face:
Bell Tower clock on Island at Lake Bled
Whilst at Lake Bled we also went and visited iconic Bled Castle and St Martin church, which are around the lake:
St Martin & Castle @ Lake Bled
St Martin has some lovely stained glass windows:
Stained glass @ St Martin in Lake Bled
The Castle, which dates back to the 10th century is on the top of a cliff and offers a stunning view over the lake:
We really quite enjoyed our visit to Slovenia, be it brief, but we would love to go back and explore more of the country.
For more pictures of our trip see [the flickr set]

A week in Paris!

I went to Paris for ADASS XXI – a computational astronomy conference – it was an interesting conference full of the wonders of GPUs (I wrote about the [conference] and my [poster] previously). anyway, I also did some site seeing as my lovely other half flew out (Birmingham to Paris is a rather short flight) and we did a weekend of site seeing… here are a few highlights:
Of course you can’t go to Paris and not go on and on about the Eiffel Tower… so I will. We went up it on definitely the worst day whilst we were there. It was very reduced visibility but oddly eerily cool:
Eiffel Tower
from the top you just couldn’t see a thing:
from top of Eiffel Tower
though later that night, it was just spectacular:
Eiffel Tower at night
A surprise highlight of my trip was going into the Galeries Lafayette, something that Elizabeth wanted to see… pretty expensive shop but one heck of a focus:
Galeries Lafayette
She also surprised me by suggesting we go to Sainte-Chapelle – I had heard of this but was blown away by the place. I supposedly looked very disappointed by the first, lower room:
Sainte-Chapelle stained glass windows
but the upper room is just “wow”:
Sainte-Chapelle stained glass windows
Sainte-Chapelle stained glass windows
We did the other tourist things, going to Notre-Dame, Sacre Coeur, the Louvre and a bunch of palaces and squares but I won’t bore you with a discussion of each (but if you want to see some pictures go take a look [at my flickr set]). The other things that really stood out to me where the awesome size of La Défense:
La Défense
and seemingly never ending Musée d’Orsay:
Musée d'Orsay
Musée d'Orsay cafe clock
Overall we had a great time and well we got a lot in in such a short stay, probably helped by the epic metro… never had to wait more than 5 minutes for a train! On that note I’ll leave you with a picture of sunset over Place de la Concorde:
Place de la Concorde
(oh and if you want to see more did I mention [my flickr set]? 🙂 )

M57 – the Ring Nebula

I occasionally use the Bradford Robotic Telescope for remote imaging… here is an image of the Ring Nebula, M57:
M57 - the Ring Nebula with the BRT

NGC2261 – Hubble’s variable Nebula

NGC2261 – Hubble’s variable Nebula taken with the Faulkes Telescope:
NGC 2261

Testing if a file exists in python

The other day I was asked a question from a friend who was trying to run a pipeline on a bunch of data but wanted to check if a file existed before processing it. In python this is rather straightforward, you could either use the os module and test if a file exists (though this might have problems with speed of accessing files):

import os
print os.path.exists(“test.txt”)

and then test if this is true or false, but you probably want to avoid race conditions. It is also much better programming standard to use a try statement, so something like:

filename = “test.txt”
except IOError as e:
print ‘Does not exist’

nice and then execute your code inside the try statement – or something along those lines with your code.