Rosetta NAVCAM images now available under a Creative Commons licence

Guest blog post by Marco Trovatello, ESA cross-media coordinator and Mark McCaughrean, ESA senior scientific advisor. 

Four-image mosaic of Comet 67P/C-G on 30 October. Credits: ESA/Rosetta/NAVCAM -CC BY-SA IGO 3.0

Four-image mosaic of Comet 67P/C-G on 30 October. Credits: ESA/Rosetta/NAVCAM -CC BY-SA IGO 3.0

As of today, we will be sharing all Rosetta NAVCAM images under a Creative Commons licence. In particular, we will be releasing them under the so-called “attribution share-alike” version of the licence, ported for use by intergovernmental organisations, referred to in short as CC BY-SA 3.0 IGO.

We’ll explain the background and how this works in more detail below, but essentially it allows you to share them with whoever you like, to publish them on your blog or elsewhere, to adapt or remix them (e.g. to add in the Eiffel Tower for size comparison purposes), or to post them on Wikipedia. You can even use them for commercial purposes under certain conditions.

You can do all of this without our additional permission, as long that you clearly credit ESA as the source. You also have to mention and provide a direct link to the licence, and if any changes are made to the images, your remix or adaptation must be published under the same licence terms (CC BY-SA 3.0 IGO). You must also not give any suggestion that ESA necessarily endorses the modifications that you have made.

Sound complicated? It isn’t at all. Here’s the credit you need to give us:

Image: ESA/Rosetta/NAVCAM, CC BY-SA IGO 3.0

That’s it (and don’t forget to make the last part a link!).

When space is really tight, in a tweet for example, it is sufficient if the original source (e.g.. your blog post containing the image) carries this credit line.

So far, so good.

For those who never heard of Creative Commons licences and how they work, let us get into a bit more detail now.

Creative Commons (CC) is a non-profit organisation that provides a free-to-use, modular suite of licences designed for the digital age. It was founded in 2001 by Lawrence Lessig, today a Professor of Law and Leadership at Harvard University, with the aim of making the exchange and usage of cultural goods compatible with a rapidly-developing digital cultural and economic world.

The CC licence suite encompasses a whole range of options designed to encourage the sharing of material, albeit with differing levels of restriction. For example, CC BY is the most liberal licence and allows sharing, remixing, and tweaking of works, even commercially, just as long as credit to the source is given. At the other extreme, the most restrictive licence is CC BY-NC-ND, which allows them to be downloaded and shared as is, with credit given, but no commercial uses and no derivative products. CC also provides tools for placing works fully in the public domain.

One of the most remarkable aspects of the CC licence suite is its comprehensibility for laypeople, with a ‘human readable’ version of each licence designed to make them easily understood and usable without having to have a background in copyright law.

While the CC licence suite has been available for quite some time, it became apparent that some of the legal backing was not entirely suitable for Inter-Governmental Organisations (IGO’s) that operate across many legal jurisdictions.

Thus, in December 2013, a working group of IGO’s, in close collaboration with CC, brought another so-called ‘ported’ Creative Commons licence suite to life. The effort was initiated and led by WIPO, the United Nations World Intellectual Property Organisation, and the working group includes not only ESA, but also other IGO’s such as CERN, UNESCO, the OECD, and the World Bank.

There are no differences between the standard CC licences and those of the IGO-ported equivalents in the ways that content is made available, only in the mediation and arbitration processes that are applied if the licence is violated. More information is available on the CC wiki.

With the licence suite now in force, it then falls to each IGO to implement it according to the materials they are making available and their specific needs. For example, CERN has started making images and some plots and graphs resulting from some of the Large Hadron Collider experiments available under CC licences.

Within ESA, we have now started implementation and intend to gradually introduce CC licencing for still and moving images to which ESA holds the full rights. As this is true for Rosetta’s NAVCAM images, these are among the first ESA works to be released this way.

In particular, we have chosen to go with the CC BY-SA 3.0 IGO licence, which allows sharing, tweaking, and remixing, even commercially, as long as credit is given as described above, and as long as any derivative works are also similarly licenced. We are also applying the licence to all NAVCAM images released to date, although it may take us a while to go back and change the credit lines for all of those images online.

In many ways, CC is similar to open source software licencing and is aimed at encouraging broad sharing of materials, whether original or derived from the original. Importantly, it is the licence used by Wikipedia and similar projects, important vectors for getting our images and other products into as many hands as possible.

Ultimately, we hope that our partners in scientific organisations and institutions throughout Europe and the world that also hold some of the rights to images and data taken by instruments paid for with national funding and flying on ESA spacecraft will also join us in releasing works this way: we are starting discussions on that now.

So why is it important for public organisations to support Creative Commons licencing? On one hand, the taxpayer funds the works created by those organisations and it seems perfectly reasonable that they be made available to the public in a timely, orderly fashion, while also recognising the rights of others involved in their creation.

And more philosophically perhaps, this quote from Creative Commons sounds very good to us:

“Our vision is nothing less than realising the full potential of the Internet — universal access to research and education, full participation in culture — to drive a new era of development, growth, and productivity.”

And, let’s be frank: we are, of course, also hoping for a wider dissemination of our content and a wider understanding of the amazing things we do at the European Space Agency.



  • Dave Harvey says:

    Is there any likelihood of Holger Sierks at the OSIRIS team joining this commendable sharing with "his" images?

    • logan says:

      Hi Dave. Most of the 'heat' have gone to OSIRIS, but think that -excepting H. NAVCAM team- public has had very little of the endeavor. No doubt this is by design.

    • Cathy Easthope says:

      I completely agree. European taxpayers paid for this mission and the data and images belong to all of us. It isn't a single person's property.

  • Bill says:

    This is great news. Thank you ESA/Navcam Team.

    Details: on earlier online image presentations, I credit the image by adding this text _to the image_: "Image Source: ESA/Rosetta" without using the exact word "Credit". And also without using the license terms "-CC BY-SA IGO 3.0"

    Do the earlier images used need to be modified to include the wording for this new CC license, including the actual "-CC BY-SA IGO 3.0" _LINK_?

    It seems that the earlier images should be good and "grandfathered" in since they do contain reference to the source of the image.


    • Yes, each image should be 're-credited' as you describe above, including mention and link of the new licence.

      Many thanks for your support!

      -- Marco

  • Ralf says:

    Great! Does this also include the prospect that many more Navcam images - or even the complete set of images acquired during the mission! - could be made available?

  • MRW says:

    This is fantastic news. Thank you! Very pleased with how the ESA appears to be listening and responding to the concerns of the public. Looking forward to those images!

    A thought on annotating images with a credit line: it would be relatively easy to write a script for a tool like ImageMagick to add a bar containing the credit text to the bottom of each image in an archive. Better yet may be to use such a script to add the credit line to the image EXIF data tags.

    • meme says:

      Yes, I don't see the problem either .. any (good) web designer could do that to thousands of html pages with images a day

  • logan says:

    This path will bring the beauty and excitement of 'ongoing' space science closer to the public as never before. Know how hard this change is. Bravo!

  • Robin Sherman says:

    How much this will increase the flow of images in the short term remains to be seen. The attempt to address these issues is, however, to be applauded and we can only hope that it will encourage some to be feel more able to share the pride and excitement in their discoveries with the public. We have got to know Mark quite well and I am pretty sure he wants to do more and is quite irked by the bureaucracy preventing everyone from learning more about this great adventure, as no doubt are many of his colleagues.

    The proposed release of more NAVCAM images leads me to ask, where? Do we have to navigate the minefield of the ESA official archives, or will a separate site be set up with a link from the main ESA homepage and this blog, or will they be posted on the existing Rosetta webpage?

    Many thanks for your efforts so far.

  • Thanks!

    As we like to say in Spain: Nunca es tarde.

  • Piotr Witek says:

    At last! I'm so glad they finally understood, that free license is a great opportunity for ESA to promote their space missions: to let their work circulate is to let people recognize there is more to space exploration than NASA. Hope we've just seen the tip of the iceberg with more free images waiting in line (Philae cams, Mars Express maybe..?).

    As we like to say in Poland: Lepiej późno niż wcale 🙂

  • Leopold says:

    fantastic! very good initiative that could serve as example

  • Johnny says:

    Just curious, we have to credit ESA as the source? You mean I can't claim I personally sent a probe to the comet to take my own pictures? Darn! j/k

  • Piotr Witek says:

    By the way, are there any Lutetia/Steins images from NavCam? as far as I understand, they are CC-licensed now, aren't they?

  • Kaetemi says:

    Concerning the CC-BY-SA license, as I've heard several conflicting opinions on this topic;
    When using or sampling the imagery to create textures for 3D models, for use in computer games, it is fairly clear that the derived texture would be under the same CC-BY-SA license. However, when applying these textures to a 3D model, and using said textures and models inside a game; does the CC-BY-SA license also need to be applied to the model and/or all other included game assets, or is only the texture itself considered a derivative work?

    • Sorry for the late (and simple) answer, I guess your request drowned in the thousands of messages we received during landing week: It is only the texture itself.

  • Yann Forget says:

    Is the images here are also under the same free license?

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