Cooking with the Stars – Chris Conselice – 05/12/11

5th December 2011

In this one-off cookery ‘Come Dine With Me’ special, we chat to Professor Chris Conselice about what ingredients make a galaxy, especially the different types of stars you can find within them.

Please note: We may or may not have Dave Lamb (him off of Channel 4) in the studio with us during the show. But listen in to find out!

So what ingredients make a galaxy?

Firstly there are main sequence stars (see left) like our Sun.

Main Sequence Stars

Planetary Nebula

But what happens when a star ends its life? Well, that depends on how big the star is, and we will speak more about this during the show. A star could end its life become a ‘Planetary Nebula’ (see right) or it might even become a ‘White Dwarf’ or a ‘Neutron Star’. The biggest stars are thought to become stellar black holes!

Also, NEW for this show, we will be doing some science that you can do in your kitchen. We got our intrepid reporters, Carl and Dan, to try and generate electricity from things that you might find lying around a student home.


The Life of a Star
For starters: we shall be serving a primordial protostar soup. From the beginning, huge clouds of dust and hydrogen start to collapse into each other, producing brand new stars called protostars.

Protostars Forming from Primordial Gas

Main course: An assorted array of stars, all sorts of shapes and colours. Once stars manage to fuse hydrogen successfully they enter the main sequence. On the diagram below thats the main belt of stars in the middle. Our sun come out distinctly average with some burning hotter and faster. Like rock stars the faster they live, the younger they die. In the bottom right are the brown dwarves, these are the stars which failed to shine. Like those who dont make it past the auditions in the X-factor.

The Hertzsprung-Russell Diagram

Dessert: The red giants!
The red giants (top right of the above chart) come when stars reach the end of their hydrogen burning life. They expand to sizes significantly larger than their original size. Below is the inner solar system. On the left is what it is like today. On the right is what it would be like when the Sun becomes a red giant! We will be toasty.

The Solar System - If a red giant lived in it!

And as an aperitif, neutron stars, white dwarves and pulsars.

A Neutron Star

A White Dwarf

For the more eagle eyed among you, this may look like the Joy Division album cover, but it’s actually the first pulsar data!

The First Pulsar


Chris’ favourite galaxy: NGC 1275

NGC 1275


And here are some photos from when Dan and Carl hit the lab in search of cheap electricity.

More Lemons!