I'm a Scientist, Get me out of here!

In Spring 2014 I took part in a wonderful outreach event called I’m a Scientist Get Me Out of Here! This initiative brings scientists and school children together using a combination of internet chat events between scientists, school children and their teachers, and question boards that scientists post answers to. The objective is to give school children a chance to meet real scientists and ask them the sort of questions they want to ask them. I found it great fun and I got to chat to a lot of students and heard what they thought about many of the big science questions of the day.

After a fortnight of regular chat events, and trying to answer as many of the student's questions as possible, I learnt that the students had voted me their favourite of all the scientists taking part that month. I was touched to hear that I had connected with so many students and I hope they had all learnt something from me as well! The reward for winning the event was a small cash prize to spend on my outreach work, which was a wonderful gift from the organisers.

I wanted to find a way to put the prize money towards a project that provided school children with exposure to real scientific research in a fun and simple way. My original plan was to produce a series of posters that shared cutting-edge scientific ideas in astronomy with school children through simple but attractive imagery. In the end I did spend a portion of the money on this project, but I also wanted to do something more proactive that would make a longer-term impact on school children across the country.

Two of the science posters made to try to explain complex scientific ideas using attractive astronomy images.
Copies of both of these posters are still available, so please message me if you'd like one sent to your school.

The British Science Association runs an excellent scheme called CREST Awards, whereby 11-19 year old school students complete projects that help build their scientific skills. The work for these is typically done in school STEM clubs, which also provide an extra opportunity for students to engage with science. You can read more about them or find out how to get involved here.

Suitable scientific projects for CREST Awards are not easy to prepare, particularly astronomy projects and this was evidenced from the shortage of such projects currently available for schools from the CREST website. I wanted to remedy this by designing a number of astronomy-related CREST projects that used real astronomy data, yet were easy for school teachers to use, and were also really fun for students.

Most astronomy data is actually free and readily available for anyone to use, including high-quality images that can be used to answer exciting and cutting-edge questions in science. It is my hope that by helping school children access this data and providing projects that allow them to study and use this data in a real scientific experiment we could enthuse the children to pursue scientific subjects in school and possibly take up a career in science. So I started designing a few projects that used real and freely available data.

As it happened at that time a local school in Hertfordshire made a request to our local STEMNET coordinator for someone to help them set up a new STEM club. I thought this would be a perfect opportunity not only to test my CREST projects, but also to work with a school going through the process of setting up a STEM club, and in doing so see the process through the teacher’s eyes.

Me with part of an inflatable Solar System I bought with the prize money
to help teach students about the planets.

Working with the school and the teachers I was able to refine and fashion the projects, making them easy to use for the teachers, while also being new and exciting for the school children. I used the prize money to visit the school regularly, give talks to the students, and advise the teachers on how to run the CREST Award projects I had designed. By being directly involved in the STEM club itself I was also able to see how the students reacted to the projects, what worked for them and what they enjoyed the most. It was a really enjoyable experience and taught me a lot about how teachers interact with students and what scientists can most helpfully provide teachers with to help them.

These projects will soon be available through the CREST website, with information for how they can be run, where the data can be obtained, and how the results can be interpreted by students and teachers. This is all thanks to "I'm a Scientist, Get me out of here!", so thank you to all involved!

Now blogging from Keele University

The last month has been rather hectic (hence the lack of posts!), having moved both house and university. I've left my position at the University of Hertfordshire and moved to Keele University in Staffordshire to take up an STFC Ernest Rutherford Fellowship. I'm very excited to be working at Keele University and honoured to have been awarded such a high profile fellowship.

Keele Hall, part of Keele University in Staffordshire

Keele University is home to a good-sized astrophysics department, with many prominent scientists working in a wide variety of areas. As well as experts in young stars and star clusters (whose interested overlap with mine), there are also researchers studying massive stars and planetary systems. Hopefully there will be lots of opportunities for collaboration while I'm here!

Now that I'm settled into my new house and my new department I hope to be able to return to active blogging - stay tuned for more posts!

Hatfield Cafe Scientifique starts tonight!

I'm very excited because today we're launching the first University of Hertfordshire Cafe Scientifique here in Hatfield! Cafe Scientifique provides an opportunity for people to gather and discuss science while having a coffee, a pint or a glass of wine. Since it was formed in 1998 almost 50 separate Cafe Scientifiques have been set up in towns and cities across the UK, and today we start the first such gathering at the Red Lion pub in Hatfield, Hertfordshire.

Cafe Scientifique in action - discussing science!
(Credit: Cafe Scientifique)

We chose to start this venture because we (a mixed group of scientists from the University of Hertfordshire) wanted to find a way to discuss our scientific ideas and research with the general public in a venue different from the lecture halls and school rooms in which we often communicate such ideas. Furthermore since there wasn't yet such an initiative in either Hatfield or the neighbouring town of St Albans, we thought it was about time there was one!

So tonight we kick off a monthly series of talks and discussions about various scientific topics. Tonight, Dr Keith Davis will be talking about Art vs Science and how our perceptions of the two cultures have changed in the 50 years since C.P. Snow's seminar lecture. The event will start at about 7pm and is completely free (though I'm sure the pub would appreciate it if you had a drink or a bite to eat while you're there). If you're in the area feel free to come along, I hope to see you there!

Star birth and the Sea Serpent

What do sea serpents have to do with star formation I hear you ask! Well normally the two may not be connected, but this sea serpent is no ordinary snake, it is the giant constellation of Hydra, otherwise known as the Sea Serpent! Within this constellation lies a very important young star known as TW Hydrae, which has the honour of being the closest T-Tauri star to the Sun.

T-Tauri stars, as I've discussed before, are young stars, named after the prototypical example T Tauri. They are stars which have almost completely formed but are still accreting some material from their surroundings, which can cause them to glow brightly. This accretion process is not fully understood and so astronomers try to study as many different accreting stars as possible so that they can better understand how this is happening and how the accretion is affecting the star.

Artists impression of the TW Hydrae star
and its protoplanetary disk (Credit: NASA)

TW Hydrae is particularly important because it is the closest T-Tauri star at a distance of only 176 light years, and therefore it is the easiest such object to study. It was first recognised as a young star by American astronomer (and later astronaut) Karl Gorden Henize, who noted extreme H-alpha emission, typical of strongly accreting objects, in 1976.

The isolation of the star, not near any other T-Tauri stars or known star forming regions, suggested to some astronomers that it might not be a truly young star. However thanks to further observations of the star a few years later it was shown to be a bona fide and fully accreting young T-Tauri star, despite its apparent isolation.

The star itself is similar to our Sun, a little less massive and therefore a little redder, but much younger. Current estimates put its age at about 5-10 million years old, considerably younger than the 4.6 billion year old Sun that we orbit.

Fortunately for us of course the Sun is not a young star, because young stars like TW Hydrae can be very volatile objects. Young stars are surrounded by a disk of gas and dust known as a protoplanetary disk. These disks are created as material falls towards the star and gathers in a disk around it, due to a process known as the conservation of angular momentum (which basically means that things that spiral in towards a star like to keep spiralling, or at least orbiting the star and this can sometimes stop the material from falling onto the star).

Material from this disk is occasionally accreted onto the star, channeled along magnetic field lines before pummelling onto the star's surface. When this material hits the stellar surface it is heated to incredibly high temperatures, approximately 3 million degrees, which causes the star to briefly shine brightly. You don't want to be near such stars when they're accreting!

The stars and motions of the TW Hydrae association (shown in red and labelled "TW Hya" and with new members shown in black) relative to other nearby OB associations (Credit: Murphy et al. 2015).

Recently astronomers have uncovered other low-mass stars in the vicinity of TW Hydrae, creating a small group of about 20-30 stars known as the TW Hydrae association. These stars are all very young and share a common motion through our Galaxy, suggesting that they probably formed together. This discovery will be useful for astronomers looking for other young stars to study, as well as for studying how stars form in groups such as these. And importantly, TW Hydrae isn't alone any more!

Why is there a giant ring of young stars surrounding us?

A few weeks ago I talked about one of the nearest (and most important) regions of star formation, the Taurus Molecular Cloud. This region however isn't alone in being a relatively nearby region of star formation, in fact it forms part of a group of such regions that circles us in the night sky and which is known as the Gould Belt.

The Gould Belt is a ring of nearby star forming regions and young star clusters that surrounds our Sun. It was first observed by John Herschel (son of the famous William Herschel who discovered infrared radiation), who noted it as a band of bright stars that circled the sky, tilted away from the plane of the Milky Way, which also circles the night sky.

The bright stars of the Scorpius-Centaurus OB association,
part of the Gould Belt of young stars and star forming regions
(Credit: Akira Fujii)

The belt was named after an American astronomer called Benjamin Gould who performed the first detailed study of the structure in the 1870s. Gould was a pioneering and prominent astronomer, the first American to earn a doctorate in astronomy, and would go on to found the Astronomical Journal, one of the most prominent astrophysical journals in the world.

In the early 20th century astronomers were able to use spectroscopy to measure the speeds of the stars in the belt and found that they were moving with similar motions. This meant that all the stars in the Gould Belt were part of a single coherent structure. The distinctive pattern of the stellar motions has also revealed that the belt is both expanding and rotating. The rotation of the belt is thought to be caused by the fact that it sits embedded within the Milky Way galaxy, which is itself rotating as well.

The system appears to be broadly flat and pancake-shaped, approximately 2000-3000 light years across, but only about 400-500 light years thick. There is also evidence that the belt isn't perfectly circular and is more oval-shaped, a distortion that is also thought to be due to the rotation of the Milky Way as it stretches and twists the belt.

Illustration of the Gould Belt across the night sky relative to the distribution of molecular clouds in our galaxy. The Gould Belt is shown in red and the Galactic Plane is shown in blue. (Credit: Nick Wright / Thomas Dame)

The discovery of molecular clouds of hydrogen gas in the second half of the 20th century revealed that the Gould Belt was made up of many such clouds. When it was later realised that such clouds were where stars form it was quickly recognised that the Gould Belt represented a major site of star formation. It is now known that these star-forming molecular clouds make up most of the mass of the Gould Belt. This includes many well known structures such as the Taurus Molecular Cloud, the Orion Nebula, and the Rho Ophiuchi cloud complex.

While there are still many stars forming in the Gould Belt there is also a considerable history of star formation dating back almost 60 million years. This has lead to a huge collection of young star clusters (such as the Pleiades and Alpha Persei clusters), many OB associations (the famous Scorpius-Centuaurus association amongst others), and a number of luminous supergiant stars (such as Antares, the bright red star in the constellation of Scorpius). Supergiants are massive stars that are coming to the ends of their short lives and these objects were most likely born in one of the star forming regions in the Gould Belt. In fact the Gould Belt includes the majority of massive stars in the solar neighbourhood.

The young star clusters and OB associations that make up the Gould Belt,
shown in 3D relative to the plane of the Milky Way.
(Credit: New Scientist)

Since the discovery of the Gould Belt astronomers have been trying to understand how such a large and coherent structure formed within our galaxy. It was first thought that it formed when a massive star exploded as a supernova. The shock wave from the supernova would have swept up huge clouds of gas, compressing them and triggering the formation of new stars within them. However, if this were the case the ring should be aligned with the Galactic Plane and not pointing out of the plane (as the above image shows), so this theory appears to be ruled out.

A recent suggestion is that the Gould Belt was produced when a massive cloud of gas collided with our galaxy, in the same way that dwarf galaxies are known to collide with our Milky Way galaxy. This collision would have lead to a giant ring of expanding gas in the Milky Way that would be inclined at the same angle to the Milky Way of the collision itself. The shock wave from this would lead to the triggering of star formation and the creation of young star clusters, just as in the structure we see today.

This theory represents the best explanation astronomers have for the Gould Belt at this present time. Recently weight was added to this theory when astronomers found evidence for similar structures to the Gould Belt in other galaxies, suggesting that this phenomena may not be that rare.

The Gould Belt is just one of many structures in our galaxy that we can observe, from local star-forming clouds up to massive spiral arms. Understanding how these structures relate to the continual process of star birth and death and the evolution of our galaxy is one of the major tasks for astronomers today. Next time you look up at the night sky and see the bright stars and star clusters that are part of the Gould Belt think of how these objects are a part of the continual evolution of our galaxy!