@PhysicsatSurrey follows NASA on twitter and a NASA tweet advertised science on the International Space Station (ISS). The project list is here. A whole series of the projects have a (ground based) lead of Paul Chaikin (a prof at New York University). I know Paul Chaikin a bit, we kind of work in the same field and so bump into each other at conferences, so I picked one project and took a look.

It is OK stuff, but note that the (462 word) description does not mention microgravity – the USP (=unique selling point) of the ISS – once, which is perhaps surprising. The only reference to space is that the samples will heat and cool as they move in and out of the sun’s light.

This experiment may have been launched into orbit by a space shuttle – estimated cost per launch a a bit less than £1 billion. They are of course much cheaper ways of heating and cooling samples.

Now this is a bit unfair, other projects do mention gravity. However, experiments on similar systems are also done in Cambridge/Amsterdam by a friend of mine, Erika Eiser. These are of course done on the ground, and yet they have suspended magic carpets and all sorts.

Both the experiments on the ISS above our heads and in Cambridge/Amsterdam are on balls of polystyrene maybe a micrometre or a tenth of a micrometre across and in water. These small balls of polstyrene have DNA on their surface. DNA is used to stick the balls together in a controlled way.

You can just buy DNA strands, call them A, B and C, such that strand A sticks to B but not C. They are cheap too, this company quotes a bit less than £1 per DNA base. Delivery to the ISS is probably extra.

So, it is perhaps a little difficult to see why it is necessary to use a £100 billion facility in orbit when rather cheaper labs Earth-bound can do similar work, but we will see what results they come up with. If I had a chance to work with an experiment on the ISS, I would jump at the chance but I am afraid they built the ISS first, then thought what can we do with it second.