Posted on 26 August 2011, 4:57
OK, it’s 750 light years away from me, so I’m unlikely ever to encounter it for myself. But there was something to make the blood run slightly colder in last week’s news that a planet orbiting a distant sun is the darkest world ever discovered.
The planet, with the catchy (and French-sounding) name of TrES-2b, only reflects a miserly one per cent of the light that falls on it from its nearby sun. Which means it’s as dark as coal. Close up, it must be hard to see against the blackness of space, and you would only know it was there by the stars it would blot out – which would be rather a lot, given that TrES-2b is the size of Jupiter.
David Spiegel, one of the astronomers to make the discovery, says: ‘It’s not clear what is responsible for making this planet so extraordinarily dark. However, it’s not completely pitch black. It’s so hot that it emits a faint red glow, much like a burning ember or the coils on an electric stove.’
TrES-2b immediately reminded me of one of the stay-with-you episodes in CS Lewis’s Narnia book, The Voyage of the Dawn Treader. In it, the Dawn Treader sails into a darkness in the middle of the open, sunlit sea and finds it a place of terror and madness, where escape again into the light seems impossible.
But it also made me reflect on the opening words of Psalm 19...
The heavens declare the glory of God;
the skies proclaim the work of his hands.
‘Glory’ is a first cousin to the words we use for light, so if the stars of the universe speak of the shining glory of God, then what do the dark objects say about him? The writer of Psalm 19 couldn’t have imagined that the night sky above him contained not just brilliant stars, but also black holes, occult planets and dark matter.
I’m interested in this because Christian theology doesn’t seem to have made much adjustment to the huge amount of new information about the universe that has accumulated in the past century. In the 1920s and 30s, Edwin Hubble and others discovered that the universe doesn’t consist of just our galaxy (as was argued at the time) but countless galaxies – at least 100 billion, according to the Institute of Physics, each containing anything from millions to trillions of stars.
So while it was credible back in the days of Psalm 19 to see the stars as a kind of celestial wallpaper, put there solely for humans to admire and praise the Lord who made them, the vast scale of what is actually out there makes that model look like over-engineering on a cosmic scale. For me, the incredible size of it all and the discovery of objects such as TrES-2b is a severe challenge to the New Testament’s assertion that the human story is critical to the story of the universe as a whole. Our size in the mind-boggling scheme of things is surely too microscopically tiny.
So what does TrES-2b tell us about God? Maybe it speaks of the hidden side of God, the God who ultimately cannot be known, the darkness of God. These themes have been explored by Pseudo-Dionysius the Areopagite and other offbeat theologians, but has its roots back in the early books of the Old Testament. On Mt Sinai, for example, ‘Moses approached the thick darkness where God was.’
So here’s to TrES-2b. A dark and unknowable world reflecting nothing but the darkness and mystery of God.