We’ve been delivering some workshop for Public Libraries in Hull over the summer, on volcanoes of the solar system, in keeping with their reading scheme space theme. But how different can volcanoes actually be? The answer is, very! But the mechanism causing them to erupt is basically the same. It’s all about pressure building under the surface. That pressure has to balance and release somewhere. That’s when a volcanic eruption occurs.
Active volcanoes are those which are currently erupting or have erupted in human history. We mainly use this term in regards to volcanoes on Earth, but the most active place in our solar system is one of Jupiter’s moons. Io is the innermost of Jupiter’s moons and is a little larger than our moon, with a radius of 1,131 miles. It has over 400 active volcanoes on its surface, produced by the gravitational pull of Jupiter creating tidal heating inside Io. This means that Io is being pushed and pulled by Jupiter, which causes friction deep inside the moon and creates this volcanic activity. Although Io has an icy surface, lava erupts hundreds of miles above the surface due to this tidal heating and low gravity.
Back to volcanoes on Earth. They erupt lava. They can occur on the surface of the Earth and also under the sea. Imagine that the Earth’s crust is a bit like a cracked eggshell. The pieces of the eggshell are the tectonic plates. Hotspots sometimes occur in the middle of the Earth’s tectonic plates and cause eruptions on the seabed with the lava cooling to rock. The hotspot itself is fixed but the plates move, sometimes creating a series of islands, like Hawaii!
Further out in the solar system where temperatures are extremely cold, a different kind of volcano occurs. Ice volcanoes. In the far reaches of the solar system on Pluto, where the temperatures are around -200 degrees C, ice volcanoes exist. Otherwise known as cryovolcanoes these icy giants tower around 3500 m above the surface of Pluto.
Although we have no observations of cryovolcanoes erupting on Pluto, there is evidence to suggest that it could possibly be geologically active. So how do volcanoes erupt ice? Well, we’re not 100% sure but imagine geological activity inside bodies like Pluto have warmed the frozen surface into a Slush Puppy! The moving ice sheets grind together inside and expel this above the surface as a cryovolcano! Unfortunately our observations of Pluto were very brief as the New Horizons spacecraft whizzed by in 2015, so we didn’t actually see any eruptions! We saw the very first cryovolcano on Neptune’s moon Triton as Voyager 2 flew by in 1989.
So Earth isn’t the only body of our solar system with volcanoes! We’ve also seen evidence of past volcanism on Mars, Venus and our very own moon! And the children in our workshops love learning about the different volcano types and designing their own!
If you haven’t managed to book onto the library sessions then we have spaces available on our own workshops (including volcanoes) in Hull, Scunthorpe and Beverley. Book online now!
Have a great weekend!
Katies, Carol, Anita and Lauren
The Lab Rascals Team xx