Cosmic Horizons

I find myself a bit on an invalid for a couple of days, but have a mountain of stuff to get through so a brief post today. It doesn't take much digging about on the internet to find people who send  a message to their previous self ; don't worry, this is not about me writing a letter to a pimply version of myself warning of all of the mistakes I will make - it would make for a very long post! But when I was recently in  Blighty , I was invited to visit a couple of my previous schools, namely  Crynant Primary School  and  Llangatwg Comprehensive School  and talk about my journey from the  Welsh Valleys  to being an astronomer at  The University of Sydney. Visiting the schools was like traveling through time. Of course, things had changed, definitely more computers and smart boards than in my day, but the layout of the rooms brought back so many memories. The best thing was meeting the children, who were keen and were prepared with a mountain of cool astronomy questions,

After a week of battling jet-lag, it's time to get back to some science. And this week, a new paper from the PAndAS , from Heidelberg based researcher,   Michelle Collins . The target here is  dwarf galaxies . Here's one from wikipedia. There's lots of dwarf galaxies out there in the Universe. In fact, in terms of number, they represent the dominant galaxies out there, but they are much smaller than our own Milky Way, so they don't have the dominant mass. Don't believe me? Well, my colleague,  Alan McConnachie , recently compiled the most comprehensive compilation of the galaxies within our  Local Group ; you can read the details  here.  So, we have three large galaxies, the Milky Way, Andromeda and  Triangulum , and then almost 100 smaller galaxies, a sea of dwarf galaxies. Now, you might think that dwarfs are simple things, just a billion or so stars living together in a dark matter halo, just a smaller version of large galaxies, but no. There are a numb

Apologies for the continued delays, but travels have come to an end, I find myself in a warm and sunny Sydney, and normal services will be resumed as soon as possible. A brief non-astronomy post. One of my other interests is history, especially prehistory, and on my break, myself and the family walks from  Port Eynon  to  Rhossilli  on the  Gower Peninsula  in Wales. This is very near where I grew up, but I never really explored it. It is a spectacularly beautiful piece of coast line, even in the sea fog. One of the reasons I wanted to visit was not only the beauty, but the history. A while ago, I bought a fantastic book called  Homo Britannicus , detailing the prehistory of the British Isles. In this book, I learnt about an amazing discovery on this very shore line, a cave containing the remains of the  Red Lady of Paviland . This "lady" is red as the bones have been died with  red ochre . I'll let wikipedia tell the whole story, but when discovered in 1823,