Commentary | Space Situational Awareness Sharing for the 21st Century

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As space becomes more congested, maintaining  a timely and accurate picture of space activities simultaneously becomes both more important and difficult. With an ever-increasing number of spacefaring entities comes the expectation of the utmost protection for their satellites. This only increases the workload for operators at satellite operation centers around the world.

International partners expect the U.S. government, as a leader in space, to head the effort in protecting each and every asset. The greatest example of this is the collision between the U.S. Iridium LLC and Russian Cosmos satellites. The net result of the incident was more than 2,000 additional pieces of debris. Considering that there are roughly 100,000 objects orbiting Earth, it becomes clear that there is a cumulative effect to such collisions. It cannot be emphasized enough that as the number of assets orbiting Earth increases, the danger and effects of collisions also increase.

The United States has an extensive network of space surveillance sensors; however, no one nation has the resources and full access to the geographic locations necessary to precisely track all orbiting space objects. To meet this challenge, the U.S. is implementing a new approach to the exchange of information regarding space objects. This approach empowers others in the space community to make more informed decisions regarding their assets, thereby reducing the dangers of miscommunication, mishaps, misperception and mistrust.

In a time when barriers to entry in the space environment are decreasing, it is beneficial to re-evaluate the utility of data sharing and its effects on spaceflight safety. Such changes should occur gradually, however, to allow other governments, international organizations and private industries to mature their space situational awareness capabilities in a deliberate fashion.

As an example of international cooperation, U.S. Strategic Command (Stratcom) has worked with multiple foreign entities, commercial and governmental, in updating the Conjunction Summary Messages currently used for notification of a predicted on-orbit close approach. The updated format was jointly developed with these partners to ensure a universal approach to space situational awareness, and such practices will be applied to formatting more data and products as we move further down the road toward greater integration.

Today, the U.S. Department of Defense publicly releases data on tens of thousands of objects. Of these, only about 1,100 are satellites performing an active mission; the bulk of the orbiting population is debris, rocket bodies and retired or inoperable payloads, many of which cannot maneuver. Additionally, there is still an indeterminate amount of small debris for which we cannot generate reliable orbital estimates. While these objects are smaller than a pebble, NASA estimates the total number of objects to be in excess of 100,000. Despite their small size, these pieces can harm satellites and degrade operations.

The long-term cumulative effect of debris in space is becoming one of the greatest hazards spacefaring entities must contend with. As an increasing number of objects fill the low Earth orbit regime, there is a risk that a tipping point exists where there is so much clustering that collisions and debris make the orbit nearly unusable. It is imperative to share as much actionable information as possible with other spacefaring parties, consistent with our national security interests.

To that end, space situational awareness data sharing is intended to improve safety and transparency in space. Due to the responsible sharing of information with like-minded partners including foreign governments, private industries and intergovernmental organizations, the space community is becoming increasingly cognizant of its environment. This sharing has become not only a mechanism to exchange data but also a transparency and confidence-building measure that has resulted in the creation of underlying norms of behavior for many leading space entities. In a relatively short period, great strides have been made in releasing U.S. information. But greater potential for opportunities to share information exists. Using a dynamic approach to space situational awareness information sharing has helped make it possible for other spacefaring entities to further develop their body of knowledge for space expertise.

The 2009 collision of the Iridium and Cosmos satellites generated the driving force behind many of the current U.S. space data sharing policies. In 2009, Congress passed legislation authorizing the sharing of space situational awareness data outside the U.S. government. In 2010 and 2011, respectively, President Barack Obama signed the National Space Policy and the secretary of defense and director of national intelligence jointly signed the National Security Space Strategy. These two documents further the importance of the responsible use of space, spaceflight safety and U.S. leadership. The space situational awareness sharing program is one way to do that.

Stratcom’s space data sharing program is designed to reduce the chances of future satellite collisions and improve the sustainability of the space environment. Prior to Stratcom assuming this mission, many budget and human resource challenges needed to be met. The first step for Stratcom was to focus on identifying information necessary for satellite and launch operators to conduct responsible space operations. Within that context, different categories of support exist, from basic support to highly tailored information for owner/operators.

There are three levels of space situational awareness support services that comprise the program. The first is emergency notifications, which alert satellite operators to potential collisions. The second level is the Stratcom-sponsored website, which serves as an available repository of basic satellite catalog information, including positional data and background information (country of origin, launch date, etc.). The third level includes specific advanced services supporting safe spaceflight operations during launch, on-orbit, and decay or re-entry operations. This third level of services is available to commercial and governmental satellite and launch operators. Together, these support services increase the safety, security and sustainability of the space domain through an enhanced understanding of satellite positional information. However, without a better understanding of the three levels of space situational awareness support it is impossible to fully comprehend this enterprise.

First, in practice, Stratcom’s Joint Space Operations Center (Jspoc) seeks to identify close approaches for active payloads in Earth orbit with any known object. On average, 20 to 30 close approach notifications are sent per day. To the greatest extent possible, the Jspoc contacts the affected owner/operator with information regarding the predicted close approach. The information provided is in the form of a Conjunction Summary Message. This information allows the owner(s)/operator(s) to make informed and educated operational decisions to protect their assets and the space environment. At no point does the Jspoc direct another entity to conduct a maneuver to avoid a potential conjunction. Stratcom products are merely advisory. Once a Conjunction Summary Message has been provided to an affected operator, the Jspoc offers to evaluate any potential maneuver to avoid a second potential conjunction in the process of avoiding the first conjunction. To give an idea of global reach, of the 1,100 active payloads in orbit today, the Jspoc currently has sufficient contact information to provide emergency notifications to the operators of more than 98 percent of those payloads.

Second, is the next level of support. For any interested person or entity, Stratcom offers this website as a source of basic satellite catalog products. Anyone wishing to access the site must acknowledge a user agreement and submit a Web-based request for an account. To date, over 88,000 total users from 185 countries have registered for an account. Considering that there are only 195 countries in the world today, Stratcom is very proud of our global outreach efforts.

Third, advanced services are designed to support safe spaceflight operations during launch, on-orbit, and decay or re-entry operations. U.S. law requires the Department of Defense to establish written agreements with satellite owners and operators, launch providers and country partners in order to permit advanced service data exchanges. With agreements in place, entities may request specific support for their operations, and Stratcom can provide this support, within resource constraints, with the caveat that it is consistent with U.S. national security interests. This information can be viewed in seven categories: conjunction assessment, launch support, deorbit and re-entry support, disposal/end-of-life support, collision avoidance, anomaly resolution and electromagnetic interference investigation. These agreements help develop relationships among the Jspoc, commercial firms’ operations centers and partner nations’ space operations centers worldwide. By exercising this valuable exchange of orbital data, Stratcom works to preserve the ability for all nations to use and explore space and provide a safer and more responsible environment.

In summary, as a global leader in space, the United States is creating a safer, more stable space environment through the responsible exchange of actionable information via the space situational awareness sharing program. By sharing this information, Stratcom is reducing the possibility for miscommunication, mishaps and mistrust. The command has recognized and is addressing many of the problems that led to incidents such as the Iridium-Cosmos collision and have turned the tide with the space data sharing program. There is now an established process to improve the safety and reliability of space today and for future generations.


Davis Florick is a space policy analyst in the Policy and Doctrine Division at U.S. Strategic Command, and Col. Lina Cashin is chief of the division.