Tag Archive for: Solar System

View the transit of Mercury on 9th May

This May will provide us with a fantastic opportunity to observe a transit of Mercury. It should be possible to view the eclipse from your school or home, but we will need to keep our fingers crossed for good weather.

What’s a transit of Mercury?

Like a solar eclipse, when the Moon obscures the Sun, a transit occurs when Mercury or Mars (the only planets between us and the Sun) partially block the view of the Sun from the Earth. A transit is much rarer than a solar eclipse. A solar eclipse may occur a few times a year, while transits of Mercury occur between 3.5 and 13 years apart, and transits of Venus come along only every century or so.

The next transit of Mercury will start just after midday on 9th May and will finish at around 7:40pm

How to observe the transit safely

The best way to observe in a group is to project an image of the Sun onto a shaded white surface using a telescope. CLEAPPS Guidance leaflet provides excellent information about how you can set this up: www.cleapss.org.uk.

However if you do not have a telescope, or the weather is poor on the day, live streams of the transit will be available on the internet.  ESA will be providing one and the link will be provided on their website closer to the event.


Never look directly at the sun!

You could permanently damage your eyesight



The Royal Astronomical Society have produced a teachers activity pack (PDF link) which contains a range of different worksheets and activity suggestions for use with primary and secondary students. The pack also supports literacy and numeracy, and features Mercury-themed cupcake investigations.

You could ask pupils to compare the size of Mercury and the Sun. They could do this by looking at the diameter of the two objects, the area of the disc, or their volume. Which approach gives the best idea of the relative scale of the two? NASA has created a solar system explorer website that will help students investigate further.



The Wonders of the Sun

Tag Archive for: Solar System

19th November: Space Maths

Today, Carol and James were back at Heworth Grange for more Space Maths. We looked at the size and scale of our solar system (using sprinkles, no less), and got up close and personal with some meteorites.

Find some more information on our space maths workshop page and make sure you check out the link to the “tediously accurate scale model of the solar system”. Seriously, you won’t regret it.

Tag Archive for: Solar System

Space Maths

Scaling and ageing the solar system, in our Space Maths workshop.

The 2015 Solar Eclipse

Think Physics’ guide to the partial solar eclipse visible from the UK on 20th March 2015.

You won’t believe the scale of this activity…

We recently had a request from a local school for a workshop that linked maths and space.  A natural fit, of course, and an example of the sort of workshop we can pull together to fit in with your teaching needs.

As a starter, we looked at the first half of the classic ‘Powers of Ten’ film:

It’s a great film to use to show the massive range of scales over which physics is useful, from galaxies to people to quarks. However, for this session, I wanted to focus just on the journey out to the edge of the observable universe.

After than we turned out attention to our nearest (natural) neighbour – the Moon.  Although the diagrams of the solar system often show the Moon as being very close to Earth, you can visualise the distance easily because the Moon is about 10x the diameter of the Earth away from us.  Using any ball to represent the Earth, wrap a piece of string around the middle of the ball ten times.  Unwrap, and there you have a nice visual representation of how far away the Moon is.

When I was teaching in a school, one of my regular activities was to make a scale model of the solar system.  The problem with the solar system is that space is BIG. It’s really hard to create a solar system model which has the same scale for both the diameter of the planets and the distances between the planets.  The activity I used for Think Physics is one which is adapted from ‘The Earth as a peppercorn,’ and there are variations on the theme all over the internet.

How big are the planets in relation to each other?

food stuffs

Objects to use in our scale model of the solar system.

There are online calculators which will allow you to do the scaling without effort, but as we were doing a maths workshop, we got out our scientific calculators and did the maths ourselves.  We used a football (diameter 20cm) as the Sun, and used scaling to work out the diameter of the planets.  If you don’t want to do your own calculations then I like the Thinkzone version of the solar system calculator.  In the picture you can see the options that I offered as possible objects that would be the right size for our model.

Having worked out that hundreds and thousands are about the right size for mercury, silver dragées work for Earth, and cherry tomatoes would be good for Jupiter, we then tried to put the objects in the correct place – using the same scale.

We used a toilet roll to help with the distances (similar to this NRICH activity) – and the students quickly realised that there just wasn’t enough space in our lab.  In fact, using our scale (the Sun as a football), the only planet we could fit into Think Lab was Mercury.  The maps show where we would have to put our objects.

The orbits of the inner planets, if the sun is 20cm in diameter.

The orbits of the inner planets, if the sun is 20cm in diameter.

The orbits of the outer planets (and Pluto) according to our scale model.

The orbits of the planets (and Pluto) according to our scale model.


If you want to do this activity – you could use the Thinkzone calculator and center the solar system on your own school – you just need your latitude and longitude, which you can find by placing a marker on Google Maps.  Students can then work out where their house is on the map, or you could even go on a solar system safari and walk the distances involved using a trundle wheel and your map.


Interactive Solar System Map

If you want to know our position in the Solar System as this very moment, there’s no better way of finding out that by visiting www.solarsystemscope.com

You can explore the position of the planets throughout history and into the future. Why not try navigating to your birthday and checking for any planetary alignments?