Monday, March 31, 2008

Space Science - Decisions, Decisions.










http://www.mpe.mpg.de/projects.html

The students on the Design in Gamma-Ray Astronomy course from the University of Sout
hampton at the University of Tenerife, La Laguna have a number of decisions to make in order to design a space-based gamma-ray telescope.

The Astronomers, Engineers and Space Scientists need to decide on which materials to use in their telescope to detect gamma-rays; how to protect -or shield- their equipment from solar flares and cosmic rays; in what orbit to
place their telescope, (working out the height and the 'eccentricity' - how eliptically the orbit is set up) and lastly, they have to determine the weight of all their proposed equipment - called a mass budget - to determine whether their rocket - launched from florida - can carry it all.
http://www.onet2.pl/dvbs.html


Transient Events in Nearby Galaxies

Transient events are bursts of energy from stars which last anywhere from a couple of seconds to a month. These events are difficult to observe because they happen very quickly and are impossible to predict!

The students in Group 6 on the University of Southampton's Design in Gamma Ray Astronomy course in Tenerife are looking for bursts of energy in galaxies outside the Milky way. There are about 40 galaxies in our local group, one of the farthest away in the group being Andromeda, which is about 2.5 million light years away (a light year is the distance that light travels in a year). Group 6 want to study bursts of energy caused by X-Ray binary systems and magnetars in galaxies in and past Andromeda.

A magnetar is a rapidly rotating neutron star with an enormous magnetic field. Magnetars eject energy which can only been seen in the X-ray and gamma-ray regions in beams from their magnetic poles. If there was a magnetar located half-way between the earth and moon, it would strip off all the magnetic data from our credit cards!

Magnetic fields cause powerful emissions from the star and it's these emissions that the students want to study. Students in Group 6 will be able to detect what elements are in the stars that they are looking at - eg. they should be able to spot titanium, iron and hydrogen in the neutron stars.
http://en.wikipedia.org/wiki/Magnetar


In order to observe very distant objects, Group 6 need to design a gamma-ray focusing telescope which includes a large diffracting 'lens' (a new technology called a Laue-lens) with a focal length of around 100 meters. Instead of having a very large satellite -which wouldn't fit in a rocket- Group 6 will fly two satellites in formation 100 metres apart. Light will be directed by one satellite onto a detector on the other satellite, in a similar fashion to the satellites shown in the illustration.
http://www.integral.soton.ac.uk/missions/GRI.html


Group 6: Judit Bakos, Yazmin Padilla Michel, Carolina Berucci, Anastasia-Eleni Tsitali, Benedict Woods and Aron Kisdi.

Sunday, March 30, 2008

A Survey of X-Ray Binaries


http://www.daviddarling.info/encyclopedia/X/X-ray_binary.html


What's an X-Ray binary? - Alex Terris - an undergraduate Physics and Astronomy student from the University of Southampton on the 'Design in Gamma Ray Astronomy' course in Tenerife - tells me that it's either "a black hole or a neutron star (a dead star - very dense) orbiting a normal star (like our sun)."

Alex and Group 5 are exploring the magnetic fields of all the X-Ray binaries in the Milky Way. There are about 400 that we know of at the moment and their mission would last about 5 years.

The group have to work out how the X-Rays from the binary systems travel, (nice animation of polarization needed here!). They want to compare the magnetic fields of different types of binaries.

(Group 5: Alex Terris, Jose Sanchez, Emilio Trigueros, Ruben Sanchez, Adam White and Michaelangelo Siracusa).


Wow, Solar Flares!

(Photo by NASA)














A solar flare is a violent explosion in the sun's atmosphere.

Solar flares take place in the outer layers of the sun, (called the corona and chromosphere), heat ing plasma to tens of millions of kelvins and accelerating electrons, protons and heavier ions to near the speed of light. The flares produce electromagnetic radiation across the electromagnetic spectrum at all wavelengths from long-wave radio to the shortest wavelength gamma-rays. Most flares occur in active regions around sunspots, where intense magnetic fields emerge from the Sun's surface into the corona. Flares are powered by the sudden (timescales of minutes to tens of minutes) release of magnetic energy stored in the corona.

X-rays and UV radiation emitted by solar flares can disrupt long-range radio communications and radar on earth.

The frequency of occurrence of solar flares varies, from several per day when the Sun is particularly "active", to less than one each week when the Sun is "quiet". Large flares are less frequent than smaller ones.

The outer most layer of the sun - the corona - is much, much hotter than the inside layers. Group 3 on the Design in Gamma Ray Astronomy course at the University of Southampton in the University of Tenerife, La Laguna, are trying to explain why that is! The reason is thought to be due to micro-flares which differ from normal flares in that they do not eject matter from the sun, but trap the accelerated particles, producing more heat as the particles collide and reactions take place. At the base of the flares, the particles which have been accelerated collide with the plasma and react, producing even more heat.

Group 3 are designing a telescope based on two separate satellites, approximately 400 metres apart, to observe solar flares and solar micro flares. The telescope uses a mask on one satellite to filter photons from the sun and focus them onto a detector on the other satellite. The second satellite uses an 'active' sheild to stop unwanted data from being processed. The shield lets all radiation through, rather than blocking any radiation, but the shield senses what wavelength of photons it is receiving and signals to the detector to ignore the unwanted data.

Group 3: Junayd Miah, Hector Brown, Tony Lap Pang, Illeana Leal and Alba Casado Jon MacRae

Um, Active Galactic Nuclei?













Group 1 were off to a tricky start on day 2 of their University of Southampton and University of Tenerife collaborative Astrophysics ´Design a Gamma Ray Telescope' project when Babel Fish translated 'initial idea' as 'tapeworm' from Spanish. Working in two languages can be a difficult business, especially when your Spanish phrase book doesn't contain the words 'Active Galactic Nuclei'.

An active galactic neucleus (AGN) is a region at the centre of a galaxy which radiates energy in many wavelengths throughout the electromagnetic spectrum.

The nucleus gives off high energy radiation like gamma-rays and the further away that you get from the nucleus the lower the energy given off eg. radio waves and infrared, visible, and ultraviolet light. A galaxy hosting an AGN is called an active galaxy. The radiation from AGN is believed to be a result of accretion on to a super massive black hole at the centre of the galaxy. AGN are the most luminous persistent sources of electromagnetic radiation in the universe, and as such can be used as a means of discovering distant objects; their evolution as a function of cosmic time also provides constraints on cosmological models.

There are lots of different types of AGN that can be observed with different electromagnetic emission characteristics. The reason that there is a difference is because of the positioning of the earth in comparison to the AGN. Jets of material are emitted from AGNs and we might observe the jets as they emit material towards earth - or we may see the jets from the side.

Group 1 are trying to design a telescope to observe AGN around the galactic plane.


Saturday, March 29, 2008

Nucleosynthesis & Fine Spectroscopy?

One of the groups of undergraduate Physics and Astronomy, and Engineering students from the University of Southampton on the Design in Gamma-ray Astronomy course in Tenerife had been given the area of 'Nucleo-synthesis and Fne Spectroscopy' to research. What's that?

James Pettler in Group 4 explained that his group wanted to observe the aftermath of a supernova - which thrusts out gases and heavy elements created as the star collapses. Fine spectroscopy is a method of identifying the radiation emitted by radioactive elements. This radiation will appear as lines on a spectrograph once they are detectected by the telescope.
http://upload.wikimedia.org/wikipedia/commons/0/00/Crab_Nebula.jpg









The group is currently working on getting enough sensitivity from their telescope's detector. The elements that the students want to observe in space do not give out a huge amount of radiation, so the more sensitive the detector the better. Also, the larger the surface area on the detector the more sensitive - and the larger the field of view too. The field of view needs to be as large as possible to study a supernova and it needs to be larger than the angular resoloution - otherwise the image will be blurred. There is though, a limit to the size of the detector that the group can use - this is determined by the limit of mass that a rocket can launch into space.
http://integral.esa.int/26al_map_annotated.jpg

Gamma-Rays

What's Gamma-Ray Astronomy?

The image above is taken of our galaxy using gamma-rays. In the same way we can use infrared to see in the dark we can use gamma-rays to expand what we can see. Gamma-ray astronomy began in the early 1960's when rockets were launched into space carrying scientific equipment which could detect both x-rays and gamma rays. Gamma-rays from space had previously been undetectable because the rays are absorbed by the earth's atmosphere.
(Photo from http://veritas.adlerplanetarium.org/science/EGRET_map.jpg)


Group 2 - UG students from the School of Physics and Astronomy at the University of Southampton on the Design Course in Gamma-Ray Astronomy in Tenerife - are looking at gamma-ray bursts. These bursts of energy come from far away outside our galaxy and -because they are from so far away- they give us an insight into the early universe; the further away the source of energy, the further back in time the energy was given off. Gamma-ray bursts are so bright that if they were visible to the naked eye they would blind us.

Group 2 are designing a telescope which can tell whether gamma-rays come from the merging of very dense neutron stars (collapsed massive stars once larger than our sun, but now approximately 10km across) - or from super novas, (exploding stars at the end of their life-cycle).



Gamma-Ray Astronomy















Day one of the University of Southampton's School of Physics and Astronomy Tenerife field trip to the University of Tenerife's Physics department. The trip allows undergraduate Physics and Astronomy, and Engineering students studying Space Science to get a taste of international research work.

Students are put into groups and given research topics to explore. By the end of the week the students are to give hour-long presentations, putting forward proposals to the group on new orbiting gamma ray telescopes.

This week-long project is run (from the University of Southampton's side) by Professor Tony Dean. Prof Dean was one of the original proposers for the INTEGRAL satellite mission, which went through the European Space Agency (ESA) selection process in the early '90s. Researchers from Southampton have been active in the mission since then, responsible for aspects of the instrument design, construction and calibration up to and beyond launch.

Students have to decide on a scientific objective for a new telescope, design the instrumentation needed for the space science mission and then work out the logistics - including the orbit of the satellites, mass budget issues (the weight limit imposed by launch constraints) and how to get the equipment into space. Students have to choose which rocket they could realistically use to place the rocket into correct orbit.

Students also have to work 'internationally´ - each group has one Spanish student in it and we have Hungarians, a South American, an Italian, a Mexican, a German and a Welshman - to communicate with.

(Students From Left to Right Illeana Gomez Leal, Jon MacRae, Hector Brown, Tony Pang)

The research topics (which I don't understand yet) are; Active Galactic Nuclei, Gamma-ray bursts, solar flares, fine spectroscopy and Nucleosynthesis, a survey of X-Ray Binaries and Transient Events in Nearby Galaxies. Each group has a member of staff supporting them in their research.

(Students from Left to right: Junayd Alam Miah and Alba Casado)

Observing Astronomers Observing

"I want you to get more enthusiastic about Astronomy" said Professor Malcolm Coe, Head of the School of Physics and Astronomy at the University of Southampton "so what about accompanying the Physics, Astronomy and Engineering undergraduate students on their field trip to Tenerife?"

- Oh it'ś a hard job being the Śchools' Liaison Officer and Light Express Coordinator for the School of Physics and Astronomy. Obviously I agreed to go on the trip! Yesterday I met with 22 students, 1 Professor, a couple of Post Doctorate Astronomy Researchers and a PhD Astrophysics student at Tenerife Airport. We then traveled by minibus from the south of the island up north, using walkie-talkies to help our convoy navigate the poorly-signed roads.

I took lots of attractive photos; pictures of the spectacular volcanic landscape (which looked as though someone had chucked large sticks of dynamite at the mountains); photos of the enormous wind-turbines turning in the coastal winds - behind them a backdrop of the turquoise ocean. I took photos of the colourful houses in the valleys as we wound our way up the mountains, their gardens decorated with beautiful flowers and spectacular cacti. They were fantastic images, I was so very pleased with myself until I erased them all by mistake while trying to use LINUX for the first time - the Scientist's alternative to Microsoft Windows.

At the beginning of day one at the University of Tenerife in La Laguna I imagined an easy 10 days ahead of light work, followed by afternoons/evenings spent on the beach - a bit of a holiday -for me and the students- surely?

"We're going to do ten year's worth of work in a week" said Professor Ismael Perez-Fournon course leader in Tenerife and member of staff at the Instituto de Astrofísica de Canarias. The students eagerly got to down to work and I realised - somewhat in shock - that I have a week to get to grips with the basics of Gamma-ray Astronomy.


Wednesday, March 19, 2008

Monkeys with Car Keys











'Monkeys with Car Keys: The Artist in Response to Culture Today.'


The private view of the second of the Bargate monument annual open exhibitions - organised by A Space was held last night.

The title of the exhibition was inspired by a fridge magnet which read: - 'Without Art we'd just be monkeys with Car Keys'.

I submitted the piece 'The Good Medicine Cabinet' which I produced during a residency at the Holocenter last year. The piece explores our reflective nature, and how it can inspire personal, spiritual, and social change.

The new Bargate monument Gallery housed 12 new pieces of artwork - chosen from over 100 entries.

Thanks to Peter Penrose for showing such interest in my work. (Top left)