Under the sea at a planetarium? Tom Jeffreys is at the London première of Coral – Rekindling Venus.

Last night the Royal Observatory in Greenwich was just one of the hosts for the global launch – in 25 countries pretty much simultaneously – of a rather unusual film. Coinciding with Venus’ transit of the sun (apparently one of the rarest occurrences in astronomy), Lynette Wallworth’s Coral – Rekindling Venus has been specially produced in order to fit the particular specifications of the massive, dome-shaped, overhead screens of a planetarium.

Produced in collaboration with Forma and Felix Media and featuring music from Antony and the Johnsons, Max Richter and others, the 45-minute film seeks to explore the incredible diversity of life sustained by the world’s coral reefs, as well as to alert viewers to the fragility of these precariously balanced ecosystems. That the film, which is being screened at the Peter Harrison Planetarium until early July, is part of the London 2012 Festival and therefore sponsored by oil giants BP (directly to blame for coral destruction off the Gulf of Mexico) is ironic at best and at worst reprehensibly hypocritical. But then, that’s often the side-effect of thoughtless corporate partnerships.

Which is a shame, as Coral – Rekindling Venus has clearly been a massive labour of love for Wallworth. Following the London première she talks with passion about the incredible coral community, its beauty, and its importance. The film’s links with the transit of Venus may be a little tenuous, but it’s hard to argue with the similarity that Wallworth herself draws between the trans-national efforts made to observe the transit in the eighteenth century and the need for a similar approach to tackle climate change today: the film, she hopes, will act as “a marker of an attempt at global scientific co-operation”. “On this sort of scale,” she adds, “territories really don’t matter.” Unfortunately one might say the same about multinational oil companies.

There’s another correlation, although again it’s a little tangential. By being screened at the Royal Observatory, but depicting a sub-aquatic world, the film neatly ties together the different institutions that fall under the banner of Royal Museums Greenwich. It also shows us that, in some ways, there are galaxies at every level, from the astronomical to the sub-atomic. Certainly, there’s a galactic feel  to Coral – Rekindling Venus as we’re plunged head-first into a whirling world of fluorescent light and movement. It takes a while to get your bearings.

Coral has a wonderful sense of rhythm – from the silent, stately sea turtle to the frenzied panic induced by a crown-of-thorns starfish. And the footage – taken across the world by scientists and researchers, with no digital manipulation – is quite breath-taking. From start to finish, it’s a beautiful cascade of sea anemones, jelly fish and strange, brightly-coloured creatures. Look out in particular for an incredible sequence of spawning brain corals.

But the film is not entirely without problems: a minor one is that in places it seems a little blurry and out-of-focus, but that may just be opening night teething problems / my eyesight. More significant is that, because of the high standards set by today’s nature documentaries, there’s not that much, aside from the format, that really elevates Coral to the status of ‘art’. And because its aims are relatively straightforward, it doesn’t leave you with all that much to ponder, other than a sheer sense of awe. But then, perhaps in this instance, awe alone is enough.

Coral – Rekindling Venus  is at the Peter Harrison Planetarium until 6th July 2012.