Lunar Eclipse 28 Aug 2007

Tomorrow morning between 07:54 UT and 13:21 UT, there will be a total lunar eclipse visible from the United States, Canada, South America, the Pacific Ocean, western Asia and Australia. A lunar eclipse is when the Earth passes between the Sun and Moon thus blocking out the light (except for any that refracts through the Earth's atmosphere). Unfortunately, Europe and Africa can't see this eclipse as we will be on the wrong side of the planet. For North America the eclipse is fairly early in the morning depending on your time zone (follow that link for times in EDT/CDT/PDT etc). In Australia the eclipse will be at a more at a much more civilized time in the evening. If you are in a part of the world that can see it, I hope the weather stays clear for you.

Posted in astro blog by Stuart on Monday 27th Aug 2007 (05:38 PDT) | Permalink

4th Birthday

Welcome to post number 700! My first post was way back on 20th August 2003. That makes it a smote over four years that I have been writing a web log. Back when blogs were first being called blogs, I insisted that I wouldn't start one and so, inevitably, started this shortly afterwards. In mid-2003, there were only a handful of astronomy-related blogs such as space.about.com and Cosmic Log, both of which are still going strong today. Without wanting to sound like the Monty Python Yorkshireman Sketch (and I am actually a Yorkshireman), a lot has changed in the past four years. Not only in the improvements in blogging software and web services, but also the increase in the number of astronomy-related weblogs. My list of blogs mostly concerning astronomy now stands at 46 and that doesn't include all the manned-spaceflight and rocket-themed blogs out there. The astro-blogosphere is a much larger place than it was.

In my last blog anniversary I commented that a Carnival of the Astronomy Blogs would be a good idea. I'm glad that Henry Cate decided to actually get one rolling and Emily Lakdawalla is currently hosting week 17. So what of the future? Well, the Carnival of Space is a great start but I think we will see even more of an online astro-blog community - including both amateur and professional astronomers - develop in the build up to International Year of Astronomy 2009. I'm looking forward to it.

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Posted in astro blog by Stuart on Friday 24th Aug 2007 (23:28 PDT) | Permalink

Ralph Alpher

According to Physics World, Ralph Alpher died on August 12 2007. Alpher was the first author of a classic paper which attempted to calculate the abundances of the chemical elements following the big bang. The paper is seen as a classic not just for the subject matter but also because of the author list. Alpher was working with his doctoral supervisor George Gamow and the story goes that they asked Hans Bethe to join the paper - published in Nature during April 1948 (April 1st?) - so that it would be referred to as Alpher-Bethe-Gamow - a physicist's joke. Shortly after that paper, Alpher and Robert Herman predicted the temperature of the big bang; many years before it was finally discovered by Penzias and Wilson in the 1960s.

Posted in astro blog by Stuart on Friday 24th Aug 2007 (15:51 PDT) | Permalink

Science imitating Art

It is often said that art imitates life. Well, sometimes, science can imitate art. This morning I was looking at some data taken with an astronomical receiver that has not yet been fully commissioned. When the data were plotted in front of me, part of my mind thought back to my GCSE art classes and the work of artist Bridget Riley. Bridget Riley created kinetic op art and I remember being fascinated by the way the curving of the lines made my eyes think that the paper was bending. Back at my computer screen I realised that the curves in my data were doing the same thing.

Perseids
On the left is part of Fall, 1963 by Bridget Riley. On the right are some data with a 50 Hz mains signal.CREDIT: Bridget Riley/Stuart
These wavy lines look pretty funky. In my case (right), they are due to electronic pick-up of an A.C. mains signal oscillating at 50 Hz (European standard). The horizontal axis is time within a second (actually only the first half of a second because I cropped it) and the vertical axis shows subsequent seconds.

If you have ever dealt with microphones or audio data you may have experience of a 50 Hz (60 Hz in the US) hum due to mains powered equipment. For both audio folks and astronomers, these signals are unwanted and can cause poor sound quality or dodgy astronomical data. You can tackle the hum by keeping cables short and shielding them. If necessary, you can also try to filter the 'bad' signals out of the data afterwards. Personally, I'm not overly concerned that they are in my data because I know their origin and I know that it won't be a problem when the receiver is used in anger. So rather than worrying about them, I can think of them as a cool op art. After all, science can be pretty artistic sometimes.

Posted in astro blog by Stuart on Thursday 23rd Aug 2007 (15:43 PDT) | Permalink

APoD Twitterings

Following on from my previous attempts to put astronomy on Twitter, and Paul Mison's ISS updates, I decided that the time had come for the fantastic Astronomy Picture of the Day (APoD) to have a place on Twitter too. On Sunday, I created an APOD account which should be automatically updated each day with the title of the latest APoD and a link to the image. Not only will it let twitterers keep up-to-date with great astronomical images, it should also provide a basic RSS feed.

Posted in astro blog by Stuart on Tuesday 21st Aug 2007 (20:12 PDT) | Permalink

Height of a Giraffe?

The arXiv (pronounced the same as archive) is a great resource to which astronomy and physics researchers can send copies of their scientific papers. That means that you, me and anyone else can often get an electronic copy of a paper without needing to find the original paper journal in a university library. Anyone can submit a paper to the arXiv and the paper does not have to be accepted to a peer-reviewed journal. The result is a complete mix of the good, the bad and the downright bizarre. It is the last of those categories that gives people things to talk about at tea break.

A week or so ago, the high energy physics (HEP) section of the arXiv had a paper by Don Page entitled The Height of a Giraffe, in which the author links the height of giraffes to constants in atomic physics. The paper builds on a previous paper (1980) on the subject which concluded that the maximum height of a human being would be several centimetres! This limit is obviously a bit out and, for some reason, neither author thinks that the gravity of the planet that the animal lives on has any bearing on its height. The giraffe paper goes on to say that a human being is approximately equal to an elephant (reminding me of people assuming a horse is a sphere to make the maths easier), so I can only assume that it is a very early April Fool's joke.

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Posted in astro blog by Stuart on Monday 13th Aug 2007 (16:45 PDT) | Permalink

ISS passes on Twitter

Via the Royal Observatory Greenwich blog, I learn that London-based Paul Mison has created a twitter feed that tells you when the International Space Station will pass over London. I don't live in London, but I can see this being quite useful for those that do, especially if you forget to look at Heavens Above regularly. The feed also gives details of Iridium flares. There is an equivalent feed for San Francisco but currently no other cities.

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Posted in astro blog by Stuart on Monday 13th Aug 2007 (13:34 PDT) | Permalink

ROG Blog

I just noticed that the Royal Observatory Greenwich have started a blog. It is only three entries old at the moment, but it is nice to see that they are making use of the twitter feeds for the Jodrell Bank telescopes. They even have a del.icio.us page too.

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Posted in astro blog by Stuart on Saturday 11th Aug 2007 (10:16 PDT) | Permalink

Perseids 2007

This weekend is a good time to see the Perseid meteor shower as the Earth slams into the tail of material left behind by Comet Swift-Tuttle. Earth's atmosphere hits the small fragments at around 60 kilometres per second and the resulting friction causes the air to glow. These fragments are called meteors but are more commonly, and incorrectly, known as "shooting stars". The best time to observe the shower is after midnight this Sunday night (i.e. very early on Monday morning) although you may see a few meteors on the nights either side of the 12th. This year we are particularly lucky because the Moon is new so won't be creating too much sky glow.

You don't need to know a lot about the sky to see the shower and Phil Plait has good advice on the 12 things you need to prepare. My advice is that you should make sure that you have warm clothes even if it is the middle of summer because it gets quite chilly in the middle of the night if you aren't really moving about. Also, get yourself a good deckchair/lawnchair to sit in to save your neck.

Below I've included an image, created with Stellarium, showing the Eastern sky at about 2am on Monday 13th August 2007. As well as watching for meteors, you can also spot the planet Mars. Mars is a few degrees above the star Aldebaran which is one of the eyes of Taurus (the Bull).

Perseids
The Perseid meteor shower as seen from mid-northern latitudes at around 2am on 12th August 2007. CREDIT: Stuart/Stellarium

Posted in astro blog by Stuart on Thursday 09th Aug 2007 (22:44 PDT) | Permalink

The Cosmos: A Beginner's Guide

Typical, I leave the country for a few weeks and the BBC and Open University go and start a brand new series about the Universe. The Cosmos: A Beginner's Guide started yesterday (Tuesday 7th August) and runs until 11th September. From the website, it looks as though this should be a pretty good series presented by Adam Hart-Davis, Dr Janet Sumner (OU) and Dr Maggie Aderin-Pocock. One of the programmes even takes a behind-the-scenes look at a certain space project I'm working on. You can even get a free Cosmos poster if you live in the UK or Ireland and DaveP has already ordered one.

Maggie Aderin-Pocock is currently a PPARC

Science and Society Fellow
and is really enthusiastic about communicating science. I talked to her a couple of years ago at a meeting about science communication and was going to interview her for the Jodcast about the instrumentation work she has done. With one thing and another I never got around to it.

By the way, is anyone taping the series? Is it being repeated?

Posted in astro blog by Stuart on Wednesday 08th Aug 2007 (12:01 PDT) | Permalink

The Moon beats Harry Potter

Every now and again I peruse my web logs to find out how many times pages on this site have been viewed. It gives me a bit of an idea of what the denizens of the Interwebs are looking for, astronomically, and I get to see if something I wrote was actually read by more than five people.

Today I looked at the summary of the past two months. As you might expect with the release of a film and the last book in the series, many people stumbled across my entry on Harry Potter and the Book 7 Star Party. However, that was only the second most popular post (third was my post about the broken ACS). The winner, by a large margin - it was almost three times as popular as the Harry Potter post - was my post about the Orange Moon I saw back in 2005. It would appear that for the past two full Moons, the atmosphere has been fairly dusty in a range of countries (particularly the UK and US) and this has led to a flurry of people trying to find out why the Moon looked as orange as it did.

What would these people have done before the Internet? I don't think that the answer to a question like this would be very easy to find in a typical library. However, not only did they find out the reason, they were also kind enough to leave me some nice descriptions of the beautiful sight they saw. The Internet can be fantastic sometimes.

By the way, I recently saw another very orange looking Moon myself. That one was due to smoke from a nearby fire.

Posted in astro blog by Stuart on Tuesday 07th Aug 2007 (18:50 PDT) | Permalink

David Attenborough Censored

OK, I can't let this pass (seen via Dave P on Twitter) without comment. David Attenborough is, together with the excellent BBC Natural History Unit, one of the finest natural history documentary makers on the planet. He has made truly stunning programmes over the years including Life on Earth (1979), The Living Planet (1984), Life of Birds (1998), The Blue Planet (showing next week on the Discovery Channel in the US) and Planet Earth (2006) to name just a few. He has even made the unpromising premise of an entire series about plants into a thrilling and captivating story in The Private Life of Plants (1995). Now, it appears that his excellent series The Life of Mammals (2002) is being censored in the Netherlands. Why? Well, the series shows fossils and refers to how life has lived on Earth for millions of years.

Dutch TV channel Evangelische Omroep/Evangelical Broadcaster have removed whole scenes (some of the video clips have Dutch captions but you should be able to get the jist) which show evidence which suggests things that do not agree with the broadcaster's world view i.e. that dinosaurs roamed the Earth, continental drift occurred, and that life has existed on Earth for millions of years. This cherry-picking of the parts of the natural world that EO like and removal of all references to those bits they don't is intellectually bankrupt and totally objectionable. Apart from that, I'm also hugely annoyed that the resulting programmes are a misrepresentation of the scientific integrity of David Attenborough.

I still find it hard to comprehend that people willingly ignore the real world where it doesn't agree with their pre-conceived notions. They seem happier to reside in their own fluffy, distorted view of reality with their fingers in their ears saying "La la la. I can't hear you". Sure I have pre-conceived notions about the world, but I'm aware of that and I'm willing to revise or remove those notions in the light of evidence.

If you live in the Netherlands I suggest that you get a hold of the original BBC version or at least watch the YouTube clips showing the omissions. Many thanks to YouTube user Obdurodon for highlighting this. David Attenborough should not be treated like this.

Posted in astro blog by Stuart on Monday 06th Aug 2007 (13:09 PDT) | Permalink

Galactic Centre Laser

The European Southern Observatory's (ESO) Very Large Telescope (VLT) is situated at Paranal, high up in the Atacama desert. The Chilean Andes seems to be littered with domes, dishes and instruments of one kind or another, and the VLT makes the largest combined optical telescope there. However, sometimes the best images don't come from the big, expensive pieces of kit. Sometimes a simple camera with a wide field-of-view and a long exposure can produce stunning results. ESO astronomer Yuri Beletsky has taken some fantastic shots showing the laser guide star shining out of the Yepun telescope at the VLT towards the centre of our galaxy which you can see beautifully in this image.

VLT, laser and Galactic Centre
The sky above Paranal on 21 July 2007. Two 8.2-m telescopes of ESOs VLT are seen against the Milky Way. The laser guide star is aimed at the Galactic Centre and both the Small Magellanic Cloud (left) and Jupiter (right) are visible too. CREDIT: Yuri Beletsky/ESO

Posted in astro blog by Stuart on Friday 03rd Aug 2007 (18:17 PDT) | Permalink

An Astronomical Performance

I've mentioned this before, but the Lovell Telescope is now in it's 50th year. In fact, the very first scientific observations - known as first light to astronomers - were taken on August 2nd 1957 and last night Megan recreated the very first observations. Considering that it is 50 years old, it is really remarkable that it is still a world-class instrument.

To officially mark the 50th anniversary of first light, Jodrell Bank Observatory is having a special musical performance. The music will be composed and mixed by Jem Finer (The Pogues) and Ansuman Biswas who have been working together since 2000. It will use sound from the structure of the radio telescope as well as use astronomical data, from the

telescope's receivers, converted into audio. To hear an interview with Ansuman and Jem, and some example sounds, listen to Thursdays Front Row (available for six more days) from BBC Radio 4. The event should be really interesting and I'm a bit frustrated that I'm in the wrong continent for it!

I think there are still a few tickets left so if you want one, contact the Jodrell Bank Visitor Centre on 01477 571339.

Posted in astro blog by Stuart on Thursday 02nd Aug 2007 (19:03 PDT) | Permalink
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