Whatever I had imagined Lichfield Cathedral would contain I certainly wasn’t prepared for a huge model of planet Earth. Called Gaia, it’s an imposing artwork by Luke Jerram.

It brought home to me just how far up the planet from the South Pole the British Isles are. From most angles of the cathedral’s floor they couldn’t be seen:-

Gaia from the cathedral choir:-

Only 24 people have ever had the chance to see a view like this – or photograph it. The 24 astronauts of the Apollo Programme who made it to the Moon and back.

From Astronomy Picture of the Day for 29/4/21, a digitally restored photograph of the whole of planet Earth from its nightside, the last picture of its kind so far to be taken by human hands.

Wow. Just wow.

From Astronomy Picture of the Day for 12/10/19.

On the left the pale blue dot (Earth) as seen from Saturn. On the right Earth and Moon from Mercury.

A stunning picture of Saturn’s rings backlit by the sun from yesterday‘s Astronomy Picture of the Day. And between them the spot of light is Earth with the tiny pinprick to its left, the Moon.

This is a view that would have been difficult to imagine seeing when I was a lad.

The sun gives out light across the visible spectrum (the colours of the rainbow) and beyond. We see the sun itself as yellow or red according to its position in the sky and what we experience as “white” light is made up of all the colours. If that light is passed through a prism or difraction grating it splits up into these colours.

What about when the sun’s rays are blocked?

Constantine Emmanouilidi caught a great picture of the sun’s spectrum split in this way but during an eclipse. This was Astronomy Picture of the Day for 15/11/13.

Thanks to Mr Emmanouilidi for permission to copy his picture.

It was through images similar to this where a line spectrum is obtained that the chemical element helium was discovered in the sun’s atmosphere before it was isolated on Earth.

The above is a photo of the Earth and Moon as taken from the Cassini spacecraft in orbit around Saturn.

A slightly different view is given on yesterday’s Astronomy Picture of the Day.

The photo was taken on July 19^th.

The JPL site (Jet Propulsion Laboratory) has more.

This picture (from Astronomy Picture of the Day 14/5/12) shows all the water of Jupiter’s moon Europa as if gathered into a ball and a similar depiction is done for Earth.

If you look at the sizes of the two spheres of water you can see Earth actually has comparatively little. It’s just spread over a large area (the oceans.) Europa has more water in total. A good place to look for extraterrestrial life then, perhaps.