08 February 2009

Star jelly

This evening there was a broadcast on UK radio 4 about the mystery of "star jelly."

You can read about it on
BBC Scotland outdoors.

Although some theories have been suggested, there is no certainty as to what "star jelly" is. It is rather unlikely that it has fallen from the stars.

When we listened to the programme, we realised that we had found some star jelly on a walk on 22nd September 2008.

It was lying on grass at the edge of a farm road and looked like featureless transparent jelly. We thought that it might be a slime mould.

We took some of the star jelly home, and when Fred examined it under his microscope he could see small black dots and transparent hair-like structures.

22nd August 2009

Today I found more star jelly. This time it was at 675m on a Scottish hill, close to a small pool. You can see it in the foreground in this picture.

The most favoured explanation now seems to be that star jelly is unfertilised frog or toad spawn which is left when the frog/toad has been eaten by a predator.

19th September 2009

The Times has published an article on star jelly today

4th November 2009

Yet more star jelly. A friend found this while we were out on a walk together. Once again, it was on grass on open moorland.

We returned on 15th November and the star jelly was still there, though it had been trampled and didn't look so fresh. We also found two more lots of star jelly, each more than 1 km apart so apparently unrelated to each other. This suggests that it cannot be uncommon, at least not in this area.

3rd October 2010

More star jelly, this time near Helensburgh.

For some more far-fetched explanations as to what star jelly is, see the New Scientist and the Mearns Leader among others.

05 February 2009

More ice spikes

Yesterday morning the temperature was around -5ºC and had become quite suddenly colder overnight. I found two ice spikes, so the conditions must have been near perfect. Unusually, neither was in the paint tray that has been so productive in the past.

The larger ice spike appeared to have frozen at its tip and produced another tip on the upper side. It had a vertical height of 38mm, though the length from the right side of the base (as seen in the 1st picture) to the tip of the spike was 55mm.

The next picture shows the large tray in which this spike had formed. It measures 52x52mm and the water depth was around 40mm.

A second spike had formed in a flooded plant pot. This one was much smaller - 30mm in height.

To the right of this spike were 3 small humps. Maybe there were 4 competing gaps in the ice, and the spike on the left won comparatively late in the process of formation.

There are more ice spikes on our website and you can read more on the website of the Physics Department of the University of Toronto.