Despite the terrible weather that has seemingly been affecting almost everyone recently, I was able to get a short glimpse of Mars (with binoculars) last night during a short gap in the clouds. I took a picture of both Mars and the Pleiades with my camera balanced with a mini tripod on a chair. I didn't get any more shots because I had spent ages playing about with my camera trying to get the correct setting.

Mars and the Pleiades
Mars and the Pleiades seen on 30th October 2005 CREDIT: Stuart
Lots of other people have details of their observations on the web; Tom (USA), Ian (Australia), Dave-p (UK) and Peter (NYC, USA).

Posted in astro blog by Stuart on Monday 31st Oct 2005 (13:45 UTC) | Permalink

Astronomy on a budget

Around the internet I've seen many websites talking about expensive telescopes, mounts and fancy CCD cameras. If you don't have a spare few hundred pounds (several hundred US dollars) to buy the latest equipment, this can be a bit depressing and you may think that you can't do any astronomy yourself. In reality there is a lot you can do without this gear and it need not be expensive; even with just your eyes there is a lot of sky to explore and it changes all the time.

For those on a budget, one of the best ways to start out in astronomy is to join your local amateur astronomy society. You should be able to find one near to where you live if you search around on the Internet. Usually, these societies are pretty friendly and there is bound to be someone who will let you look through their telescope. They will also be able to tell you about what you are looking at and show you how to get the best use of a telescope. Someone may even sell you an old telescope second-hand.

If you can spend a small amount of money, you could buy a cheap department-store telescope or get some second-hand binoculars from a car-boot sale. Again, your local astronomical society will be able to give you advice on buying a telescope, or binoculars, from their own experiences. Another cheap means of getting your own telescope is to make one yourself just like the great John Dobson. This method does take time but it can be a lot of fun and you really will know how a telescope works by the time you've built it.

Until recently I didn't own any kind of optical instrument other than my eye and a digital camera which I have used to take pictures of the Moon, Jupiter and the International Space Station. Last weekend I acquired my brother's binoculars and I hope to make use of them soon to look at interesting stuff in the sky, especially now that the weather has improved. Now, I must start thinking about building my own telescope...

Posted in astro blog by Stuart on Thursday 27th Oct 2005 (18:57 UTC) | Permalink

Questions for a rainy day

For the last few weeks we have had nothing but cloud and rain. The last few days have seen it raining cats and dogs which is not good when you have to cycle to work and then spend all day with wet feet. It also means that observing has been out of the question, although I did catch a brief glimpse of some stars on the way home tonight. Only briefly though. Hopefully, November will provide better weather.

This week is half term (school holidays) and yesterday I got to be the astronomer in an 'ask an astronomer' session. I find it daunting to be an 'expert' in front of a room full of people, but it is a lot of fun. I've noticed that it is usually better if a kid asks the first question though, as this encourages the other kids to ask questions too. Strangely, questions from ten year olds tend to be a lot harder than the questions from adults because the kids know more about space and haven't learnt that it isn't cool to think about stuff.

Yesterday the kids were on fire; they had an impressive amount of knowledge and asked some fantastic questions. Amongst them were "How do we know that the Sun is 8.3 light minutes away?", "How do you measure the speed of a solar prominence?", "What is the smallest star?" and "What happens at the centre of a black hole?". For the last question I told the young lad that nobody is quite sure, but if he thought about it for a few years he might be able to figure it out. It would be great if he did.

I really hope those kids keep their enthusiasm in the world around them as they get older and never stop asking questions. I am trying to savour the warm fuzzy feeling.

Posted in astro blog by Stuart on Tuesday 25th Oct 2005 (22:01 UTC) | Permalink

Are the times a-changin'?

How do you tell the time? Most people will answer that question by looking at their watch, clock or computer, but how do those devices know the time.  If you are like me, they were probably set from the TV, the speaking clock or those on-the-hour 'pips' broadcast on the BBC World Service. For most people this is good enough. You usually don't need to know the time to better than a few seconds as it usually doesn't matter if you are one second late to a meeting. However, there are a lot of things in the modern world which do need to know the time quite accurately. One application of accurate time is in the global positioning system which is being used more and more these days.

Time also has a lot of applications in astronomy because the Earth rotates. As it rotates, the Sun, Moon and stars appear to move across the sky - rising in the east and setting in the west slightly less than every 24 hours. So, if you want to take a pretty picture of your favourite object, you need to know where it will be and when, otherwise you won't catch it. This is just the sort of information you need to catch a train, although that doesn't necessarily help for the local trains that I use.

In astronomy, if you get the time wrong, you could miss the star, galaxy or nebulae that you are trying to observe. In your backyard this isn't really a problem, as you can have a fish around the area where you think it should be. However, big professional telescopes cost a lot of money to operate and if you are paying for it you don't want to waste time searching for things - you just want to point and shoot. This is especially true when you are trying to observe faint objects that you can only see with a long exposure time.

For a number of years astronomers have made use of Universal Coordinated Time (UTC) or Universal Time (UT) to know precisely what the time is to within a small fraction of a second. UTC is set by a number of atomic clocks around the world which measure oscillations in caesium atoms and gives a time accurate to roughly 1 part in a thousand, thousand, billion. But, the Earth doesn't behave nicely. It slows down over time and occasionally speeds up as happened after last December's tsunami. The result is that over time, the time as measured by the position of the Sun (due to the rotation of the Earth) gradually goes out of step with atomic time. To fix this problem, leap seconds have been occasionally added over the last thirty years to keep solar time and atomic time together.

Now, a proposal to remove leap seconds has been put forward to the International Telecommunications Union (ITU) and will be discussed next month. Abolishing leap seconds has the advantage of making computerised time systems simpler to implement, but at the cost of the time getting out of step with the position of the Sun.

Ultimately, over a very long time, this could mean that the Sun may end up rising at 8pm and setting at 8am. Although this would take a long time at the current rate (21 seconds over 30 years), professional astronomers would have to give up on UTC a lot sooner than that. As you might imagine, the Royal Astronomical Society (the professional body for astronomers in the UK) is not happy about these plans and recently released a response to the International Telecommunications Union (ITU). Can they take on the vested interests of the computer industry and the military and win? It doesn't seem likely.

Talking of time, the last Sunday in October (this weekend) sees the end of summer time in Europe, so remember to put your clocks back one hour and have an extra hour in bed. Other parts of the world change at different times - Tasmania changed a few weeks ago - so make sure you have the right time.

Posted in astro blog by Stuart on Monday 24th Oct 2005 (23:52 UTC) | Permalink

Light Pollution NW

Having attempted to take images of the ISS from here in the North-West of England, I thought I would post a picture taken looking back at Manchester from on-board the ISS. The image (below) was taken during mission ISS010 on 19th November 2004 at 19:21 GMT. You can see Manchester glowing away in the centre surrounded by Liverpool (upper left), Crewe (bottom centre), Sheffield (bottom right), Leeds and Bradford (right). You can even make out the M62 motorway joining Liverpool, Manchester and Leeds. In case you were wondering, I live just below the very brightest dot in the centre of the picture.

The UKs North-west from the ISS at night

Light pollution in the north-west of England see from on-board the ISS (ISS010-E-7733) CREDIT: Image courtesy of the Image Science & Analysis Laboratory, NASA Johnson Space Center.

Now think about how much electricity is being wasted to light up the night sky. Help to reduce carbon emissions, save money and improve your chances of seeing the Milky Way in one easy step; turn off some of those unnecessary lights!

For loads of other great images taken by astronauts on the ISS and the Shuttle go to the Gateway to Astronaut Photography.

Posted in astro blog by Stuart on Thursday 20th Oct 2005 (23:08 UTC) | Permalink

International Year of...

Hopefully you are aware that we are currently in the International Year of Physics. As Megan now mentions, 2009 could become the International Year of Astronomy to mark the 400th anniversary of the first use of the telescope to look at the sky. The Royal Astronomical Society are backing the proposal as well as the International Astronomical Union and Italy. It will be up to the United Nations General Assembly to agree.

Posted in astro blog by Stuart on Wednesday 19th Oct 2005 (22:21 UTC) | Permalink

Horizon on Titan

This week, the BBC's main science programme, Horizon, will be all about the Cassini-Huygens spacecraft and its trip to Saturn's moon Titan. It will be broadcast tomorrow night (Thursday) at 9pm BST on BBC 2.

Amongst the results that the programme will discuss should be a feature on the radio astronomers who came to the rescue of the Huygens lander. During descent onto Saturn's largest moon, one of the two data channels (channel B) failed and would have meant the loss of at least one of the experiments. However, by using very long baseline interferometry - linking lots of radio telescopes on the Earth to simulate a radio telescope the size of the planet - it was possible to get some of this data back and this became known as 'channel C'. Hopefully Horizon will tell us a bit more about what happened as well as show us some of the fantastic images that Cassini has sent back.

Posted in astro blog by Stuart on Wednesday 19th Oct 2005 (22:03 UTC) | Permalink

Episode 2

OK, so last week I was appalled at the dodgy astronomy in the first episode of Supernova. More importantly, I didn't think it was too funny. This week I have changed my mind as the second episode was much funnier and I have come to think that the scriptwriter may be using astro babble in a tongue-in-cheek way.

The turning point for me was when the two young Australian astronomers tuned in to a Russian-dubbed episode of Doctor Who. They both burst out laughing at the use of 'lithium-beryllium' in the TARDIS because it was bad science. So, the bad astronomy may be deliberate and I somehow felt there was less than last week anyway.

The main set-up joke was about seeing the 'face of God' in a wormhole. It was just a tad obvious as to what the resolution would be but I thought it was quite well done nevertheless.

I shall now gently lower myself from my hyper-sensitive astro-geek high horse.

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Posted in astro blog by Stuart on Tuesday 18th Oct 2005 (21:55 UTC) | Permalink

Stellar competition

The European Southern Observatory are running a competition to win a trip to the Paranal Observatory in Chile. Before everyone gets too excited, entry is only open to students of European schools and those in Chile. That rules me out. The ESO websites says:

Just like astronomers do, you can form teams to research your chosen object, and use scientific detective work to find out as much as possible about it. Younger contestants can take part in the competition by making a drawing of the object you have selected. You could also choose as your topic a celestial event or phenomenon, such as a solar or lunar eclipse, the Northern or Southern Lights, or a meteor shower like the Leonids. Or, write about a visit to an observatory, describing the ways in which it studies the object you have chosen.

If you happen to be a European youngster, give it a go. You can even team up with two of your friends and submit a joint entry.

Posted in astro blog by Stuart on Tuesday 18th Oct 2005 (17:50 UTC) | Permalink

Blue Marble: Next Generation

You may remember a few years ago that NASA released the beautiful 'blue marble' images of the Earth. These were created by piecing together many small images and exaggerating the heights of mountains. They were stunning. The Earth Observatory have released a next generation of the blue marble images which have a spatial resolution of almost 500 metres. There are also images for each month of the year, so you can see how the snow/ice cover varies with the seasons. Even in the days of Google Earth/Maps, I still think these images are fantastic.

Blue Marble: Next Generation
An image of the entire Earth (clouds subtracted) CREDIT: Reto Stöckli/NASA

Posted in astro blog by Stuart on Saturday 15th Oct 2005 (22:43 UTC) | Permalink

Impact Craters

If a five mile wide comet hit the Earth, how much damage would it do? What about if it hit sedimentary rock - would the crater be bigger or smaller than if it hit crystalline rock? Were the makers of the movie Deep Impact even close to getting things correct?

A University of Arizona website lets you find out what sort of impact would result from your own design of comet or asteroid. You can choose the size, density, velocity, angle of impact and then place yourself however many miles/kilometres you like from the impact site. Once you've filled it the details, the site will tell you what the conditions are likely to be where you are. You can find out vital information such as the local wind speed caused by the blast, the size of the crater, how long you would be irradiated for, how long it would take the ejecta to reach you and much more.

Most lumps of rock that I tried caused big craters and destroyed large areas of the surface of the planet but it turns out that to alter the rotation rate of the Earth or alter its orbit, you need a truly huge impact - we are talking about a collision with an object bigger than Moon. Mind you, if you've read How to Destroy the Earth you already know that destroying the planet is much harder than you may have been led to believe. Thankfully the current Earth-Destruction Alert Level is at "Green".

Posted in astro blog by Stuart on Saturday 15th Oct 2005 (00:13 UTC) | Permalink

Chinese Astronauts

China has successfully launched its second manned space mission according to BBC News. The spacecraft, launched by the Chinese National Space Administration (which is strangely quiet about it on their English website), took off from Jiuquan in the Gobi desert today. On board were astronauts Fei Junlong and Nie Haisheng who will be spending five days in orbit around the planet. Xinhau have lots of coverage of the mission on their website.

Chinese Astronauts

Astronauts on Shenzhou-6 spacecraft talked with their family members in the Beijing Aerospace Command and Control Center CREDIT: Xinhau

China aims to build its own space station within the next five years and eventually send a person to the Moon. Sound familiar? It should do because it is similar to the human spaceflight plans of NASA and ESA. It seems that we are probably at the start of the second space race, only this time there are at least three main competitors.

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Posted in astro blog by Stuart on Wednesday 12th Oct 2005 (18:26 UTC) | Permalink

Astro Babble

For years I have watched the various Star Trek incarnations and let them off with the techno-babble as it generally wasn't too bad. In the Next Generation they did a fairly good job of getting the astrophysics correct and that was probably due to the science advisor (Andre Bormanis I think). The worst astro babble I saw was in an episode of Voyager involving getting stuck inside the event horizon of a black hole. What was the problem? They have faster than light engines for goodness sake.

I bring up the topic of astro babble because tonight I saw a TV programme containing the most astro-babble I think I have ever heard in a single half-hour. I thought Armageddon was bad with astronomy. The programme was a new comedy series named Supernova that has been created by UKTV in Australia. It was shown on BBC2 and is a six-week run.

Astro babble, like techno-babble, is the term used to describe sentences of complicated astronomy words that characters speak. Generally these sentences have absolutely no meaning and are put in a script to make it sound technical. In Supernova I imagine that the script writer cut out the words in The Space Atlas (which I'm not knocking as I have a copy of my own), threw them in the air and built up sentences from the result. The whole of the first episode revolved around a black hole (no puns intended) which seemed to be 'moving out of range'. The astronomers were able to catch it with their telescope after zooming past planets, nebulae and galaxies. Have none of the production crew ever used a telescope? Arrghh.

I had built my hopes up for an astronomically correct (within reason as it is TV after all) comedy series, so felt a bit let down. Personally, I didn't think the comedy was too great either as Australia and the UK can do much better. Despite all my complaints, there were a couple of moments that I found funny.


Posted in astro blog by Stuart on Tuesday 11th Oct 2005 (23:04 UTC) | Permalink

A point or not

Yesterday I caused some confusion and annoyance which I didn't mean to do. Dave-p had posted a good blog entry about a recent letter to Astronomy Now (a UK based astronomy magazine) and I used a poor choice of words to link to his post. It was late at night and I was tired, but that isn't an excuse.

Dave makes plenty of good comments about why he is an amateur astronomer:

...the motivation for getting outside came from the enjoyment there was to be had in conducting my own little experiments, in getting to know my own equipment, in expanding my own experience and in the simple joy of learning something.

Although I don't have my own telescope (I have to beg and borrow from other people) I agree with all those sentiments. You don't always have to be solving the deepest unknown problems in astrophysics  - working out how to polar-align a telescope is difficult enough sometimes. One of the greatest things about astronomy is just looking at the rest of the Universe and perhaps finding something new (to me, if not to the rest of the world). It is amazing that we've been able to work out so much of what is going on in the Universe from the confines of our little planet.

Posted in astro blog by Stuart on Tuesday 11th Oct 2005 (13:22 UTC) | Permalink

Moon Watch

It is some time since I mentioned Einstein Year (also known as the International Year of Physics) but after reading a post discussing the point of amateur astronomy [Note the fun is sometimes the point], an item from the Institute of Physics's interactions newspaper caught my eye. The article was describing how Her Majesty's Nautical Almanac Office (HMNAO) are conducting a mass-participation experiment to observe the Moon. No telescopes are required.

HMNAO provide official dates for diary publishers, some religious groups and other organisations. Amongst the dates they provide are the dates of the phases of the Moon. I'm sure everyone has seen the little symbols in diaries, on calendars and near the weather forecast in newspapers. To work out when the first slim crescent of Moon will be visible from a particular location on the Earth, a model is used. The main problem with the current model is that most of the observations that go into it are from the Southern Hemisphere and the Middle East, and therefore it isn't too accurate up in the north. To help refine the model that is used, and create a massive experiment in the process, HMNAO would like as many people as possible to spot the crescent Moon and submit the sighting to the Moon Watch website.

If you would like to take part, read the details on their website and then go outside looking for the Moon on 3-5 November or 2-4 December. As the Moon will be near the Sun at these times, you should start looking for it very shortly after the Sun has set (don't look at the Sun) near the western horizon. You'll only have about half an hour or so to catch the Moon before it too sets. Even if you don't spot the Moon HMNAO say they want to know about it. The first results are expected in December.

Posted in astro blog by Stuart on Monday 10th Oct 2005 (22:44 UTC) | Permalink

Partial Lunar Eclipse

Residents of Europe and Africa had the chance to see the annular solar eclipse last Monday. Unfortunately, in the UK we were mostly looking at cloud (it has been constant for a couple of weeks now).If you live elsewhere in the world and felt you missed out on the eclipse, you can experience a partial lunar eclipse on October 17th. Greatest eclipse occurs at 12:03 UT.

In the Americas you should see the eclipse at moon-set whereas western Iran, Pakistan, India and Malaysia will see it at moon-rise. If you live in any of those parts of the world you will only see part of the eclipse; the Moon will be below the horizon for some of the time. If you are lucky enough to live in Australia, NZ, Japan, Alaska, western Canada and the west coast of the US you should get to see all of the eclipse. Of course, the weather could conspire against you. I hope you have clear skies wherever you are.

Posted in astro blog by Stuart on Saturday 08th Oct 2005 (23:46 UTC) | Permalink

Cut-out and keep

When I was at DPS2005, I picked up a rather nice European Space Agency teacher's resources bag that was being given away. I dug it out this evening to have a look through the contents and discovered a cut-out and build model of the ExoMars rover.


An artists impression of an Exomars rover CREDIT: ESA

When I was little, I loved making paper/card based models of things. After much cutting and glueing of flaps I would eventually have a fully working theatre (with flats, curtains and actors), ocarina or perhaps even the Sydney Opera House. So I set about making the Exomars rover, but quickly discovered that it hasn't been totally thought through. It would appear that the build instructions have been printed on the reverse side of the parts. Not only do the instructions get cut up as you build the rover, but they don't tell you important things such as where to fold etc. Perhaps I got a trial version of it.

I had a look around on the interweb for more comprehensive instructions and discovered that a large number of other space missions also have their own cut-out models. ESA has models for Integral,SOHO, and Mars Express. There is also a model for NASA's Mars Pathfinder.


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Posted in astro blog by Stuart on Saturday 08th Oct 2005 (21:16 UTC) | Permalink

Wheel trouble

Tom has been reporting the progress of the Hayabusa spacecraft and its mapping mission of asteroid Itokawa. However, according to BBC News, the craft has lost the second of its three 'reaction wheels'. These are used to maintain a position in space, so when they fail it means that the spacecraft could start tumbling. At the moment the craft is relying on the one remaining wheel and its thrusters, but that uses up precious fuel. I worry that with two wheels gone after only a few months the remaining wheel might not last long enough to complete the mission. It would be a shame because the plan is to return a sample of the asteroid to the Earth.

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Posted in astro blog by Stuart on Friday 07th Oct 2005 (00:49 UTC) | Permalink

A moon for 2003 UB313?

If you remember back to the long distant past of July, you will remember the discovery of a possible tenth planet. It still goes by the name 2003 UB313, but Mike Brown (one of the co-discoverers) has updated his web page to say that, just like 2003 EL61, it appears to have its own moon. How cool is that?

The moon currently goes by the even snappier name S/2005 (2003 UB313) 1, but Mike Brown and co-workers are using the code name Gabrielle (to go with Xena) as it is easier to say. Here is the latest image of the pair taken using the adaptive optics system at the W.M. Keck Observatory:

2003 UB313 and moon
The planet appears in the centre, while the moon is the small dot to the right (3 o'clock). CREDIT: W.M. Keck Observatory

Mike Brown rules out the dot being a star as it moves with 2003 UB313. In fact, the line at the bottom is a star that has been smeared out because the camera was following 2003 UB313. Another worry was that it could have been an artefact of the adaptive optics system. However, if that was the case, Mike says that it should create an arc around UB313 during the course of one night.

Finding a moon is important because it allows the mass (how much stuff there is) of UB313 to be calculated. All you need to do is work out how long the moon takes to complete one orbit and know how far it is from the bigger body. You could work out the mass of the Sun using the Earth in a similar way - science is great like that!

Posted in astro blog by Stuart on Sunday 02nd Oct 2005 (10:16 UTC) | Permalink

NGC 1350

This image is of the spiral galaxy NGC 1350, a galaxy which is probably a bit bigger than ours - the Milky Way - and is around 850 85 million light years away from us. The image was taken in the year 2000 with the European Southern Observatory's Very Large Telescope (VLT) based at Cerro Paranal in Chile. The VLT produces some fantastic results but doesn't have the fame of the Hubble Space Telescope.

NGC 1350

A colour-composite of the spiral galaxy NGC 1350 taken with FORS2 at the ESO Very Large Telescope. The image, totals 16 minutes of observations. CREDIT: ESO/Henri Boffin

A galaxy such as this one is made up of around 100 billion stars. You can't see the individual stars in this image as they are too small - they add up to that diffuse glow making up the spiral arms. The blue tint indicates that a lot of these stars are quite young and massive in stellar terms. The rest of the smudges and blobs (a highly technical term) that you can see in this image aren't stars but other galaxies. If you click on the image, you will get the bigger version of it in which you can see all those other galaxies a bit better. Can anyone spot the galaxy that looks like a rocket?

If you want to look for this galaxy yourself, it can be found in the constellation Fornax (the Furnace) at a declination of -33, so you will need to be in the southern hemisphere to get a good look.

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Posted in astro blog by Stuart on Saturday 01st Oct 2005 (12:41 UTC) | Permalink
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