LOFAR planetarium shows at the University Community day

As part of the University's 60@60 Community day on Saturday 30th June 2012 the Soton Astrodome team, lead by myself (Sadie Jones) put on 5- 1 hour long LOFAR-UK themed planetarium shows for the general public.

Members of the public were lured into the Physics & Astronomy Department by a 'dummy' lofar antenna outside the building seen below.

When inside the department members of the public were invited to sit on the mats in our planetarium and watch a 50 minute show. These shows involved watching 4 short videos followed by an interactive tour the night sky above Southampton, including several LOFAR images using the (FREE to download) Stellarium software.

The first video was an edited version of 'We are Astronomers' which detailed how astronomers in general use the Electromagnetic Spectrum to do exciting astronomy.

The second video was an edited version of the What is LOFAR ? video made by ASTRON. In this edited version I focused on the simple and cheap antennas used by LOFAR and it's ability to look at all the sky, all the time. This video also details the use of LOFAR for looking at pulsars, transients and space weather.

The third video shown was about the building of the LOFAR-UK station in Chilbolton and is introduced by Professor Bob Nichol from Portsmouth. This video also features me (Sadie), as one of the PhD students (aka. free labour) wielding a hammer and attaching the amplifier to an LBA. Featured also are many other PhD students from other Universities such as Portsmouth & Oxford. I end this video along the lines of Professor Bob's final thoughts on aliens with some ominous scary music and an image of a massive aliens. To see the video (made by the Uni of Portsmouth) on youtube click here.

The fourth and final short film shows the million galaxies imaged by the Sloan digital sky survey. This movie ends by going right out to the Cosmic Microwave Background (CMB) at the edge of the observable universe. I explain that lofar will be used for similar radio surveys and will hopefully reveal a further 10 million active galaxies. It will also look at the Epoch of Reionisation, a time just after the big bang (after the CMB radiation) when the Hydrogen from the early universe was starting to form galaxies.

The interactive Stellarium show featured both optical and lofar images of M87, M101 and the Crab Nebula.

The first planetarium show which started at 10am was for staff members from the Faculty of Physics and Applied science and their families. The first show included mainly young children with their parents, including Professor Rob Fender and his wife and children.

The remaining 4 shows (at 11,12,2 & 3pm) were all full to capacity with 30 people in each and contained manily adults with only 10% of the rest of the audience children.

We got asked so many great questions from members of the community and they were all really excited by the fact this 'cheap' radio telescope was both 'local' and doing such exciting astronomy.

I posed 2 questions to those who came to the show. One question for the adults and another for the children. Some of the best answers to the questions are shown below:

Question for Adults

What are your thoughts on the LOFAR telescope?

'Excellent for new astronomy. Great way to Explore"

'Why didn't 'we' do this earlier ?'

"I'm stunned by the cooperation of different countries and the extent of the communication & integration from those countries"

"LOFAR LO GOOD!"

"What good value this type of Astronomy is!"

"Good to see what can be done with a reasonable budget with good collaboration across Europe/World"

"I think the mechanisms that causes jets to be emitted from black holes and neutrons stars is the most interesting thing LOFAR will teach us"

Question for Children

Have you learnt anything new today? What did you learn?

There is a big telescope in Chile

LOFAR stands for low frequency telescope!

We learnt that there are lots of stars in the galaxy.

Telescopes are great to look at.

I learnt about black holes !

It is so great!

We learnt that black holes are very big!

We learnt about lots of things :)

The future sees us improving on of this prototype LOFAR planetarium show and then making use of it for other open days and in local schools (probably for A-level and GCSE Astronomy students). We aim to get as many people excited about LOFAR as possible:)

Aliens in the Universe talk

Lancing College

I have given this talk on aliens in the Universe on many occasions. Some of the most memorable times was to Foxhills school who brought along approximately 90 primary school children to the university or at the INTECH stargazing evening. At Intech I gave the talk 3 times to families and members of the general public and each show sold out :). I recently gave this talk at Lancing College which is an amazing place, reminded me a lot of Hogwarts (see right).

Included within the talk about Aliens/Life in the Universe, the students are asked to become the planets in the solar system by holding the inflatable planets and getting in order. The students in the audience are then encouraged to decide if the planets are in the correct order if they should be changed. I then try to create some discussion over which planets in our solar system are most likely to harbour life . 

Contents of Talk

Questions from students

This talk always spurs loads of questions, so many that I often have to leave many questions unanswered.

The alternative history of Radio Astronomy

I wrote this history for my thesis but apparently it's 'too colloquial' and 'not relevant' - so this is the edited version, which I've made more colloquial and crazy times...(Papers you may want to read, if you are that way inclined are in  curly {} brackets, just go on arXiv astro-ph and you should find them).

Below is a piccy of me standing on one of the radio antenna at the Very Large Array, just cos that's the kind of rock and roll thing I do generally.

Standing on a Very Large Array Antennae

I start this story of radio astronomy with James Clerk Maxwell in 1873. Maxwell had prooven that visible light was not the only type of electromagnetic radiation, and that actually there was a wide spread of wavelengths either side of the optical spectrum. Inspired by these findings Heinrich Hertz set out to both create and detect electromagnetic radiation, in particular the longer wavelength radio waves {Smith74}. Hertz' work on electromagnetic radiation was held in high regard, resulting in the unit of frequency (Hertz, abbreviated to Hz; equal to one wavelength per second) being named after him. In 1887 Hertz succesfully discovered radio waves; but he was a modest man was Mr Hertz, oh yes,  he did not predict any use for this long wavelengths of radiation that our eyes could not detect. Luckily Guiglielmo Marconi was not as short-sighted and set about to use the radio waves to transmit signals across large distances.

 While Marconi was trying to sending signals across the Earth the likes of Thomas Edison and Sir Oliver Lodge started an attempt to detect radio waves from the Sun. As you do! However, no solar radiation was detected since the detectors available at the time were not sensitive enough and the experiments were actually set up to detect the wavelengths of radio emission which are intercepted by our ionosphere. Bit silly, but hindsight is a wonderful thing...

The birth of radio astronomy finally came in 1932 when Karl Jansky detected radio waves from space while carrying out intereference experiments for Bell laboratories. Jansky was able to determine three possible sources of intereference for communication systems: local thunderstorms, distant thunderstorms and a mysterious signal that occured 4 minutes later every day. The fact that the mysterious signal was coming from a certain direction in space which was fixed relative to the stars, but not fixed with respect to the Earth or Sun allowed him to identify its position as the centre of our galaxy, the Milky Way {Jansky33}.  So what is this mysterious-ness at the centre of our galaxy huh?? This achievement led to the unit of flux density (Jansky, abbreviated to Jy) being named after him.

Further developments in radio astronomy were hindered by the Second World War. However, amateur radio astronomer Grote Reber had been inspired by Jansky's work and took on the challenge of building his own steerable parabolic reflector dish, 30 feet in diameter. As you do!

With his device he was able to map the radio sky and show the startling differences between the optical and radio sky for the first time {Smith74}. Reber published his work in 1940 and 1942 and at the end of the war astronomers collected these findings together with the radar research of scientists such as James Hey. Hey and many other scientists had been employed by the military to improve radar and communications. Hey and his colleagues reported on the efficieny of army radar equipment and investigated reports of jamming by enemy transmitters. These reports led to findings that active sun spots emit radio waves in the metre wavelength region and were later followed up by radio observatories in Sydney and Cambridge. Hey also discovered that meteors leave trails of ionisation in the upper atmosphere which reflect radio waves and that a fluctuating signal coming from Cygnus was a result of the terrestrial atmosphere and that the source itself trasmits steady radiation. Later in 1944, van de Hulst calculated the wavelength of the hyper fine hydrogen spin-flip transition and found that it lay at 21cm, which lies in the radio regime. Astronomers were then able to use radio techniques to trace the motion of this hydrogen gas and map the spiral arms of the Milky Way. Our Earth, orbits the sun in the Orion arm of the Milky Way, and our sun is just one of over 400 billion stars in our galaxy......

The Milky Way

The earlier discoveries acted to catalyse the science of radio astronomy and as radio detectors improved there came the discovery of the cosmic microwave background and pulsars.

In 1965 Penzias and Wilson were studying radio emission from the Milky Way and found a source of noise they could not explain. At first they thought it had something to do with birds poohing on their reciever, so they cleaned it but the noise was still there. Then they realised the noise source wasn't even coming from our galaxy.... This background noise eminated from outside our galaxy with a temperature of 2.7K. Then amazingly, this temperature fitted with an earlier theory that radiation from the Big Bang would have a temperature about 3K. Oh My golly gosh!huh?

Also in the late 60's, Anthony Hewish and Jocelyn Bell working at Cambridge were using a dipole array of 128 elements and found a signal of regular radio pulses due to beamed radiation from strongly magnetised neutron stars {Hewish68}, they had discovered pulsars. At first they thought they had discovered Little Green Men (LGM) aka Aliens, but well they hadn't, nope , just some rapidly rotating neutrons stars...Now you may not think this is that awesome, but it is I can assure you, and when I saw Jocelyn Bell walking down a corridor when I was working in Oxford Uni last Easter, I was very star struck, because here in front of me was the discoverer of pulsars, I mean forget Lady GaGa, this is the real deal as far as inspiring women go, I think!! (Controversely she didn't get the Nobel prize for discovering pulsars, her supervisor did..but hmmm i shan't comment on that). By the 1970's several radio interferometers had been built in an effort to improve the resolution of radio imagery, this now means we can see deep into the centre of active galaxies and resolve jets of material which emerge from the supermassive black hole at the centre.

My thesis is basically based on Very Large Array (VLA) data of an active spiral galaxy (looks a bit like our Milky Way but with a bright 'active' centre, maybe some jets from centre) , which is why there is a picture of me standing on it (the VLA that is, not the active galaxy). But also you should be aware that the VLA is an example of one of these early interferometers which has been around since the 60's. It might also interest you to know that "AIPS" which is the program used to reduce radio images (usually by foolish PhD students who probably niaevely chose radio astronomy ) is based in FORTRAN, which is a rather old programming language (from the 60's)...however, please don't let me mislead you because if you love FORTRAN and can code FORTRAN , that by no means suggests you can use AIPS with ease....Banana Banana. 

Although I may sound pessimistic about my own radio astronomy research I would like to make you aware that at the moment radio astronomy is thriving. What I mean is alot of new and exciting interferometers are being built, and with the building of new devices comes the need for researchers to look at all the masses of data they create, i.e. this means alot of jobs have been recently created in radio astronomy, which is good. LOFAR which is currently the worlds largest telescope (never mind radio telescope) is currently expanding, with antenna based all over the world. And in 2012 they might decide where the SKA will be built, this will be an awesomely sensitive radio interferometer, with very good resolution also..


...so basically the future is radio bright, the future is ..........radio astronomy.

Radio Astronomy & LOFAR Talk at Brookfield School

I gave the talk to an after-school astronomy club, consisting manily of year 9's on an accelerated GCSE program. There were 7 students present and their teacher. The talk was ~45-50minutes long with questions at the end which lasted a further 15 mins. The students also asked many questions during the talk.

Talk Overview 

The talk was mainly about Radio Astronomy in general and why LOFAR is such a new exciting telescope. I begin with why I myself got into astronomy, from my GCSE's, then into the electromagnetic spectrum, explaining that radio has the longest wavelength. 

Talking about radio waves follows into my radio research using the Very Large Array (VLA) telescope in New Mexico, USA . I try to explain how interferometry works. High angular resolution is particularly important for looking at the active galaxies (galaxies with an active centre i.e. jets spurting out from galaxy) because astronomers still don't know how jets work. Seeing deep into the core of the galaxy where the jet is will help astronomers to understand what is happening. I also explain the 2 different types of black holes; supermassive and binary, with a major focus on active supermassive black holes which I study.

M87- Jet in active galaxy- resolution increasing.

From my research where I investigate the relations between X-ray radiation from the disk of active galaxies to Radio from the jets of active galaxies, I go into talking about LOFAR.




LOFAR


LOFAR is a real-time multiple sensor array, specifically designed to detect radio emission below 240MHz. It's a revolutionary device in that utilises electronic beam steering rather than mechanical pointing and uses low-cost dipole antenna instead of as the dish type antennas of the VLA. The base of array is in the Netherlands, and when complete will consist of 36 apeture array stations distributed over an area with a diameter over 100km. Several international stations have been built in UK, Germany, France and Sweden, achieving resolutions of 0.2 arcseconds, with the largest baselines across Europe of the order of 1500 kms.  I was lucky enough to help build many of the Low Band Antenna (LBA) at the LOFAR UK station during June 2010, (see Image below). One of the Key Science goals of LOFAR is the Epoch of Reinoisation which is the time at the beginning of the universe, when it was a few hundred million years old (about a twentieth of its current age) and objects started to form out of the plasma of the Big Bang!

Square Kilometer Array (SKA)

The location of the SKA has been shortlisted to Australia or South Africa with a decision being made in 2012. This array which will create a telescope with a collecting area equivalent to a dish with an area of about one square kilometre and combines three different type of antenna. It will combine high frequency dishes (like the VLA) with low frquency apeture arrays (like LOFAR) to provide continuous frequency coverage from 70 MHz to 10 GHz and will become the world's best imaging and surveying telescope.

 

Having fun after final LOFAR LBA antenna was finished.

I started the talk at Brookfield by explaining why LOFAR is so different to radio antenna most people are aware of (VLA antenna, dishes). I explained how we built the 96 LBA antenna at the new UK site in Chilbolton, and showed them a video of us making the telescope from YouTube where Professor Bob explains how LOFAR works and about the Epoch of Reionisation. After explaining all about this time in the universe, when the first stars and quasars (black holes) were being created I then tried went on to explain about the Neutral Hydrogen 21cm. It is is this wavelength of Hydrogen which we associate with this time in the universe, but the frequency has been redshifted to low frequencies, below 240MHz and can therefore be detected by LOFAR. 

This led me into explaining Doppler shift and showing spectrum where various atomic lines had suffered red or blue shift, I think this part of the talk went over alot of their heads but some of them seemed to understand quite well.

I finished the talk by explaining spin off in Technology from Radio Astronomy. I think it is important to put these in since we need to show how important it is that science and astronomy are not allowed to stop due to government etc cutting the money...I start with the  invention of wi-fi which earned Australian astronomers 200 million AU Dollars (all of which they are ploughing back into the new square kilometer array, SKA telescope) . I also talked about Satallite Navigation systems, a spin off from Cambridge radio astronomers trying to find accurate postions of their movable antenna with respect to their fixed antenna to carry out radio interfermetry.

Questions and Thoughts

 

The majority of questions from the students were about black holes and jets. There were some very good questions about how black holes form in the early universe, as opposed to the normal, end of a star life, and a good question about why a galaxy should rotate in a certain way.

There was only one or two questions about the LOFAR antenna which manily related to the lack of moving parts and why there needed to be so many of them. All questions after talk went off onto a tangent about worm holes, time-travel and E=mc2 and what happens when a black hole comes to the end of it's life....very good questions, shows they were thinking alot during the talk...but maybe not thinking so much about radio astronomy :P... I had a good go at answering all these and explained to them that with regards to jets and exploding black holes, astronomers are still preety clueless, so this is why we need intelligent people like them to become astronomers and help us work it all out . Finally just as I was leaving one boy asked me for advice on buying an optical telescope (which I was unable to help with :P).

Suggestions for Future Talks

Happy overall with science content.

Need more science relating to LOFAR (specifically with the UK antenna that has been added)

Obvious interest in black holes, so tie in black holes to LOFAR.

Better explanation of Doppler and Red Shift.

More stuff on black holes relating to sci-fi stuff, time travel etc.