How much does it cost to land on a comet?

Today, the space probe Rosetta’s lander Philae made spaceflight history by touching down on the surface of a comet. We’ve produced an infographic making sense of the cost of the project. Please share it!

We’ve also started making translations of the infographic (it’s in nine languages so far!), so please share them in your local language if you like!

So what do we get for our €1.4bn? Rosetta is both an astounding feat of engineering (catapulting a tonne of spacecraft across billions of kilometres of space and ending up in orbit around a comet just 4 km across) and an extraordinary opportunity for science (allowing us to examine the surface of a lump of rock and ice which dates from when the Solar System formed).

Like a lot of blue-skies science, it’s very hard to put a value on the mission. First, there are the immediate spin-offs like engineering know-how; then, the knowledge accrued, which could inform our understanding of our cosmic origins, amongst other things; and finally, the inspirational value of this audacious feat in which we can all share, including the next generation of scientists.

Whilst those things are hard to price precisely, in common with other blue-skies scientific projects, Rosetta is cheap. At €1.4bn, developing, building, launching and learning from the mission will cost about the same as 4.2 Airbus A380s—pretty impressive when you consider that it’s an entirely bespoke robotic spacecraft, not a production airliner. On a more everyday scale, it’s cost European citizens somewhere around twenty euro cents per person per year since the project began in 1996.

Rosetta has already sent us some stunning images of Comet 67P/Churyumov–Gerasimenko and today’s landing has provided us with our first close-up glimpse of the chaotic surface of this dirty snowball (as well as other valuable scientific data about the comet’s composition). If you’re a sci-fi fan, then, you might consider the mission to have been worth its price tag just for the pictures. The total cost for the Rosetta mission is about €3.50 per person in Europe; based on the average cinema ticket price in the UK (€8.50), it has cost less than half of what it will cost for you to go to see Interstellar .

So huge congratulations to the team at ESA for landing Philae on the comet’s surface! It’s not often you can make history for half the price of a cinema ticket.

All the data we used in this infographic are available in a Google Spreadsheet.

UPDATE: In light of the comment below we’ve slightly updated the graphic to include the non-EU members of the European Space Agency. There is a full explanation below, and you can see version 1.0 of the graphic, for reference.

UPDATE: The text of the article has been changed to reflect that the attempt was successful!