Actors, security, and privacy: should you be concerned?

What are the issues to deal with more actors and improved resolutions?

Our first article aimed at giving you the keys to navigate the world of satellite images and invent your own use case. Then, we studied the different processings the images required to be useful. However, one major question remains: who owns the data and how to acquire it?

As the conception and launch of satellites are expensive, the cost to enter the market is high. Rationally, satellite owners are the most powerful government spatial agencies such as NASA (USA), CNSA (China,) or ESA (Europe) but also some private actors like Airbus or Maxar.

Once acquired, these images need to be treated in order to offer navigable maps. Again, a variety of actors offer such services, with few public and free actors and many private ones. Nonetheless, this wide diversity of satellites, ownerships, and the highness of the current resolutions do not come without concerns.

Controlling satellites is not for everyone

When analyzing imagery satellite owners, three business models can be identified:

  1. Governmental agencies: NASA (USA), ESA (Europe), and ISRO (India) own their satellites. If the European and American organizations offer a large and free distribution, India prefers to restrict access to the armed forces
  2. Governmental agencies working with private companies: the Chinese (CNSA) and Korean (KARI) agencies own their satellite but granted the distribution labs to private companies, respectively Space Will and SIIS Sensors
  3. Private companies such as Maxar, Airbus, or more recently Planet Labs
Headquarters of imagery satellite owners

Unfortunately, tiles rarely come for free

Satellite tiles are particularly useful for anyone wishing to work on well-processed pictures without having to choose a specific satellite provider. With zoom level going from 0 (the entire planet) to more than 20 (depending on the providers, the largest zooms are often a pixelated version of a smaller one), this notion allows to easily access the GSD (Ground Sample Distance) determined by a specific use case. Zoom level 19 offers a GSD of 0.30 meters at the equator, corresponding to approximately 0.21m in France.

Besides, if tiles are usually free to visualize online, the conditions concerning their download, price, resolution, and update frequency largely vary from one provider to another. For instance, the French Government aims to guarantee free access to its data through its solution Géoservices, offering a resolution of 20cm. If it may suit some use cases, the low update frequency (maximum every five years) is a major drawback for any application aiming at analyzing quick evolutions from one frame to another or requiring regularly updated inferences on an area.

Other providers offer an improved update frequency, such as Google delivering weekly updates for the most crowded places of the USA, or Geoserve with data from 2013 to today. If they frequently offer the opportunity to freely navigate the map online, each provider defines its own rules regarding: the option to massively download tiles and store them as a database, the price to acquire data, or the opportunity to request old and current tiles. Hence, a benchmark of these providers, adapted to your use case, is necessary. For instance, it would not be possible to use Google Maps or Bing tiles for a tool in a production environment as they forbid massive downloads.

Should privacy and security be a subject of concern?

Since the first photos taken by the U.S Explorer 6 in 1959, satellite image resolution has tremendously increased. With a 30-centimeter resolution for panchromatic images, satellites now have the ability to distinguish very clearly some fine details. Even if the clear identification of a person with such a resolution remains nearly impossible, this quick evolution raises concern. The first one was formulated by governments themselves, worried about the ability to visualize military or other critical installations. As done for the Velizy-Villacoublay airport used by the French President, these installations were pixelized to prevent infrastructure studies based on satellite images. If these facilities are protected against civilians having access only to commercial data, the problem remains the same when another country wants to spy on your infrastructure. The only safe answer would be to hide your facilities under a building.

Military airport of Vélizy-Villacoublay, France credit: Google Earth

If national facilities are safe, yours are not as much. If you can easily blur your house on a service like Google Street View, the same does not apply to services like the satellite view of Google Maps, Google Earth, or even on the French service Géoportail. Indeed, as stated in the Guidelines 3/2019 on the processing of personal data through video devices by the European Data Protection Board, “Recordings from a high altitude only fall under the scope of the GDPR if under the circumstances the data processed can be related to a specific person”. But how will it evolve when satellite images will enable people identification from space? How to handle the fact that every country has different rules regarding the processing of these pictures and that every actor with a satellite (regardless of their nationality or public status) will be able to identify you? This is still an open question.

The rise of private actors in the space sector, illustrated by the 250 satellites of Planet Labs, SpaceX or the state-of-the-art resolution of some of the private actors (cf Table below), comes with an unexpected problem: the satellite traffic jam. With nearly 6,000 satellites in April 2020 and more than half useless, the way humans are using space is becoming a subject of concern. Adding satellite destructions as done by Russia and which created around 1,500 fragments, the astronauts’ security in the International Space Station or the observation of distant planets are becoming sensitive. It is important to highlight that the Russian action was not prohibited by international laws. Surprisingly, space activities are poorly regulated. As an example, you simply need to register your satellite to the United Nations and check the emitted frequencies with the IUT (International Telecommunication Union) to avoid interference to launch your own satellite.

Table summarizing available satellite resolutions
Debris in the Low Earth orbit, the region of space within 2,000 km of the Earth’s surface. Photo courtesy of NASA ODPO

Conclusion

If satellite images are widely available, their owners are rare. Even if ESA and NASA have demonstrated their will to facilitate access to their data, a large part of the actors sell their data.

Concerns are raised about this activity. The multiplication of satellites (and not only imagery satellites) threatens astronauts’ security and increases the complexity of astrophysicists’ works. If even the best available resolution does not allow to identify a person from space, it is a matter of time and regulations should probably be adopted.

This article marks the end of our series on satellite images and their associated use cases. We hope these 3 articles helped you to discover the variety of satellite images and their usages, the processing and the storage they require, and the influential actors in this domain.

References

European Data Protection Board, Guidelines 3/2019 on processing of personal data through video devices, January 29 2020, <https://edpb.europa.eu/sites/default/files/files/file1/edpb_guidelines_201903_video_devices_en_0.pdf>

Peter Schottenfels, October 5 2020, accessed February 2022, <https://blog.google/products/maps/how-do-satellite-images-work/>

Wikipedia, February 9 2022, accessed February 2022, <https://en.wikipedia.org/wiki/Satellite_imagery#ASTER>

Wikipedia, February 28 2022, accessed February 2022,

<https://en.wikipedia.org/wiki/Google_Earth#Controversy_and_criticism>

The Conversation, June 18 2014, accessed February 2022

<https://theconversation.com/ruling-on-sharper-satellite-images-poses-a-privacy-problem-we-can-no-longer-ignore-28133>

Laurence Nardon, March 2022, ‘Satellite Imagery control: an american dilemma’

Megan M. Coffer — Center for Geospatial Analytics, North Carolina State University, Raleigh, North Carolina 27513, United States; http://orcid.org/0000-0003-3188-4729

Dr. Shyama Prasad, ‘Pre-Processing & Correction of Digital Image’, <http://www.dspmuranchi.ac.in/pdf/Blog/Pre-Processing%20&%20Correction%20of%20Digital%20Image.pdf>

France Soir, ‘Mais au fait, qui gère quoi dans l’espace’, July 31 2020, <https://www.francesoir.fr/societe-science-tech/mais-au-fait-qui-gere-quoi-dans-lespace#:~:text=Un%20trait%C3%A9%20international&text=Chapeaut%C3%A9es%20par%20le%20Comit%C3%A9%20des,trait%C3%A9s%2C%20accords%20et%20conventions%20internationaux>

[1] https://www.piqsels.com/en/public-domain-photo-sxmje

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