The Space Reviewin association with SpaceNews

GSSAP satellites
While Russia is experimenting with rendezvous and proximity operations missions, the US military has been doing such missions for years, including the recent GSSAP spacecraft. (credit: US Air Force)

Dancing in the dark redux: Recent Russian rendezvous and proximity operations in space

<< page 1: the mysterious Objects E

Deep space moves

Mysterious Russian satellite maneuvering has not been limited to just LEO. On September 28, 2014, a Proton-M SLV was launched at 20:23 UTC from Baikonur Cosmodrome. Onboard was a satellite built for the Russian Ministry of Defence and Federal Security Service (FSB), which was destined for the GEO region. The actual name of the satellite was somewhat of a mystery. Russian state media referred to the satellite as “Luch,” a name usually used for satellites that are part of the Russian Satellite Data Relay Network (SDRN), a constellation of civilian satellites in GSO that are similar to NASA’s Tracking and Data Relay Satellite System (TDRSS). However, according to Anatoly Zak, several Russian manufacturers involved in the program referred to it as “Olymp” or “Olymp-K” in public documents, leading him to suspect that the public declaration of “Luch” was a bungled effort to create a cover story for what is effectively a military satellite.

In the case of the September 28 launch, the way Luch eventually got to GSO was largely consistent with a typical Proton-M launch.

In addition to uncertainty over its name, there is also a lot of uncertainty about the mission of Luch. The name and satellite bus it is based on indicate it is likely performing some sort of communications or data relay function, and is perhaps a military version of the real Luch satellites. Some initial reports have indicated that it might serve as a signals intelligence (SIGINT) platform, while others indicated it was providing some sort of a reference signal to boost the accuracy of the Russian GLONASS satellite navigation system or testing out laser communications equipment. Many outside observers have their doubts about all of these theories, although most suspect some sort of SIGINT or communications role.

At this point it is important to pause and discuss how satellites get to GSO, which is a more difficult and lengthy process than getting to LEO. The geostationary belt is by definition 35,786 kilometers (22,236 miles) above the Earth’s equator and at zero degrees inclination (i.e., following the Equator.) This means all satellites going to GSO need to conduct several maneuvers to get there, and there are many different approaches that are used. The fastest, but most energy-expensive, method is to launch the payload(s) and an attached upper stage into a LEO parking orbit of a few hundred kilometers altitude. Shortly thereafter, the upper stage executes a large burn to place itself and the payload(s) into a highly elliptical geosynchronous transfer orbit (GTO), which has its perigee at the LEO parking orbit and apogee at or near GSO. After several hours, the satellite will reach apogee and execute another large burn, either itself or with an apogee kick motor, to circularize its orbit near GEO. This is the method typically used by the Briz-M upper stage.

GSO profile
Typical five-burn, nine-hour flight profile for a Briz-M to inject a payload into GEO. Image credit: International Launch Services, Inc.

The slowest method to get to GSO, but one that is increasingly popular, is to use a GTO that has a very high apogee, sometimes on the order of 100,000 kilometers (60,000 miles). The reason for this is that it makes it much more efficient to change the inclination—the more elliptical the orbit, the slower a satellite is moving at apogee and the less energy it takes to conduct a plane change maneuver. The satellite then conducts many burns over a much longer period of weeks or months to slowly lower apogee, raise perigee, and zero out its inclination to reach GSO. This technique has risen in popularity due to the increased use of electric propulsion systems on communications satellites, which are less powerful than traditional chemical thrusters but much more fuel efficient. Some companies are even switching to all-electric satellites that forgo chemical propulsion entirely.

Once a satellite has reached the GEO region, it’s far from done. GSO can be thought of as a large, circular racetrack with all the cars going in roughly the same direction at roughly the same speed. A newly launched satellite needs to “merge into traffic” and find a slot in the lineup, sort of like a car coming back into the race from pit road. In the case of a GSO satellite, the slot is the equatorial longitude over which it wants to provide services. If the satellite is a communications satellite, this slot will often be registered with the International Telecommunication Union (ITU) to keep enough distance between other satellites transmitting on the same frequencies in order to prevent radio frequency interference (RFI).

A GSO satellite can change its slot, or longitude, by raising or lowering the altitude of its orbit. Raising the altitude of its orbit means the satellite will move slower relative to the rest of the GSO satellites, and thus appear to drift westward through the GSO belt (from the perspective of an observer on Earth). Lowering its altitude means the satellite will move relatively faster, and thus appear to drift eastward. Satellites are sometimes maneuvered into one slot for initial checkout, and then maneuvered again to reach their operational slot. Sometimes a satellite may be moved to a new location to replace another satellite that is being retired or serve new customers. And in some cases, multiple satellites occupy the same slot in what’s called a cluster. Usually, all the satellites in a cluster belong to a single satellite operator and they follow a very closely-choreographed dance to prevent collisions.

Even after a GSO satellite has reached its operational slot, it is still constantly maneuvering. While in a slot, a GSO satellite is continually affected by orbital perturbations due to the bulging of the Earth and the gravity of the Sun and Moon that work to pull it north-south or east-west. Most active GSO satellites execute periodic station-keeping maneuvers to counteract these perturbations and keep it in the orbital “box” for its mission. At the end of their life, satellites are also supposed to conduct a set of maneuvers to boost their orbit into the graveyard region at least 235 kilometers (146 miles) above the active belt in accordance with the IADC space debris mitigation guidelines.

What this all means is that it is much harder for analysts at the JSpOC to track and catalog objects going to and in the GEO region compared to LEO objects. Newly launched objects going to the GEO region make many maneuvers, sometimes over weeks or months, and could follow any one of several different strategies. Finding them requires searching millions of cubic kilometers of space, a much harder task than surveillance of polar LEO orbits. Often while this process is ongoing, the JSpOC does not publish updates for the orbital elements of the satellite, making it difficult for outside observers to know where it is as well.

Observers began to wonder why it stopped at this location, noticing that there were no Russian satellites in the area. However, this location did place Luch right in between two operational Intelsat satellites, Intelsat 7 and Intelsat 901 , where it remained until mid-September.

In the case of the September 28 launch, the way Luch eventually got to GSO was largely consistent with a typical Proton-M launch. The initial set of burns placed the Briz-M upper stage and payload complex (meaning the two were still connected) into an initial highly elliptical GTO of 498 by 35,684 kilometers (309 by 22,173 miles) with an inclination of 46.3 degrees. The JSpOC cataloged the complex as the first piece from the launch, satno 40258 (Object A). At this point, the Auxiliary Propellant Tank (APT) separated from the complex, its fuel having been expended for the initial GTO burn. Roughly nine hours after launch, the Briz-M upper stage executed a burn to (mostly) circularize the orbit at 35,764 by 35,589 kilometers (22,222 by 22,113 miles) and also zero out the inclination. After separating from the payload, the Briz-M then conducted another burn to boost it out of the active GEO belt and into a disposal orbit of 41,089 by 35,688 kilometers (25,531 by 22,175 miles), in accordance with the IADC debris mitigation guidelines. The Briz-M upper stage and the APT were cataloged on October 4 as satnos 40259 (Briz-M R/B) and 40260 (Briz-M Deb Tank), respectively. Satno 40258 was renamed as Luch (Olymp) by October 16.

However, once in orbit, the normal pattern of behavior for Luch ended. The launch process left Luch at approximately 57 degrees east longitude, roughly due south of Yemen and the tip of the Arabian Peninsula. It originally began to drift eastward, towards the Indian Ocean, but around October 7 changed its orbit to begin drifting westward back towards Africa at a relatively high rate. Towards the end of October it began to slow its drift rate, and around October 28 appeared to settled into position at around 52–53 degrees east. The only known Russian orbital slot nearby was that of the Express AM-6, a Russian commercial communications satellite that was launched on October 21, 2014. Luch stayed in this general area for nearly three months.

In late January 2015, Luch began to move again. By January 31 it had begun to drift eastwards again, at what began as a fairly high rate and slowed over time. It eventually arrived near 95–96 degrees east longitude, almost due south from Myanmar, around February 21. Observers once again wondered why Luch was in this area, and hypothesized that it might be due to the presence of the Russian Luch5V satellite, which was launched on April 28, 2014.

Around April 4, 2015, Luch began to move again. This time it began to drift westward at a lower rate, eventually coming to a stop around 18.1 degrees west, due south of the very western tip of Africa, on June 25, 2015. Observers began to wonder why it stopped at this location, noticing that there were no Russian satellites in the area. However, this location did place Luch right in between two operational Intelsat satellites, Intelsat 7 at 18.2 degrees west and Intelsat 901 at 18 degrees west, where it remained until mid-September.

Screenshot of the status of GSO satellites near 18 west longitude as of September 21, 2015. Source.

On September 25, 2015, Luch left its parking spot between the Intelsat satellites and began to drift again, heading westward.

As of September 29, 2015, Luch had not yet been registered with the United Nations Office of Outer Space Affairs.

But everyone else is doing it

The RPO activities of the four Russian satellites described above, and in particular those of Cosmos 2499 and Cosmos 2504, have created a significant amount of concern within the US national security space community. They have reportedly been the subject of classified briefings to US Congress on space threats, and part of the current political push for a more aggressive US space posture. Yet, based on the evidence of their activities in orbit, it is hard to determine exactly what has caused such concern, particularly since these Russian RPO activities are very similar in nature to US RPO capabilities that have been developed and tested over the last decade, supposedly for peaceful purposes themselves.

Looking back across all three Rockot launches discussed earlier, there is clear evidence of an organized testing program.

The first similarity is that it appears that Russia and China are taking a similar approach as the United States in moving towards more collaboration among the government, industry, and universities, and more rapid space technology development using small satellites. The US military, and in particular the National Reconnaissance Office (NRO), has had a program for several years to encourage university research and development programs for small satellites, including offering “ride shares” on US national security space launches. The Yubilyeniy program is a joint effort by a Russian company, JSC-ISS (Joint Stock Company-Information Satellite Systems), and a university, SibSAU (Siberian State Aerospace University) of Krasnoyarsk, to develop small satellite technology. Perhaps Russia has put in place a similar rideshare program for their national security space launches as well. Meanwhile, China recently debuted its Long-March 6 SLV by placing 20 university and research institute cubesats into orbits of roughly 530 by 520 kilometers (329 x 323 miles) in LEO, which is likely a sign of its own government-university partnerships and rideshare program.

Looking back across all three Rockot launches discussed earlier, there is clear evidence of an organized testing program. All three “Object Es” share very similar physical and radiofrequency characteristics, which appear to be linked to the Yubilyeniy-2 platform. Each launch also appears to have tested or demonstrated increasingly challenging activities. The first satellite, Cosmos 2491, separated from the rocket body and transmitted, but never maneuvered. The second satellite, Cosmos 2499, did all the activities of 2491 and also conducted a series of maneuvers to rendezvous with its upper stage. The third satellite, Cosmos 2504, did all the activities of 2499 but also appeared to bump into the Briz-M it was orbiting near.

The incident with Cosmos 2504 was also not the first time two robotic satellites bumped during RPO. In 2005, the NASA Demonstration of Autonomous Rendezvous Technology (DART) satellite bumped into a US Navy communications satellite, the Multiple Paths Beyond-Line-of-Sight Communications (MUBLCOM) satellite, during an attempted RPO. NASA’s public version of the mishap report provides some details as to why the collision happened, but other details are still classified. In 2010, two Chinese satellites, the SJ-12 and SJ-06F, appeared to bump during another RPO, under what appeared to be very similar circumstances as DART and MUBLCOM, albeit at about one tenth the velocity. All four spacecraft from these two minor collisions appeared to be unharmed, and no additional debris was created.

It is also worth noting that the Russian and Chinese RPO activities appear very similar to that of other US military satellites, notably the XSS-10 and XSS-11. Both were part of a series of US Air Force Research Laboratory experimental microsatellites designed to develop and demonstrate a satellite-oriented space logistics and servicing capability. XSS-10 was launched on January 29, 2003, as a secondary payload on a Delta II rocket carrying a US military GPS satellite. After the GPS satellite was deployed and the Delta upper stage conducted its passivization burns, the XSS-10 was released. It then conducted a pre-planned series of RPO maneuvers near the Delta upper stage, eventually closing to within 50 meters (165 feet).

XSS-10 plan
XSS-10 RPO mission plan. Image credit: AFRL

XSS-11 was launched on April 11, 2005, and according to the official fact sheet, proceeded to “successfully demonstrate rendezvous and proximity operations with the expended rocket body [that placed it in orbit].” The fact sheet also states that over the next 12 to 18 months, the spacecraft would “conduct rendezvous and proximity maneuvers with several US ¬≠owned, dead or inactive resident space objects near its orbit.” This would demonstrate the capability to not only conduct RPO with a nearby space object, but also to detect, track, and locate other more distant space objects for RPO. However, it is impossible to verify whether or not these activities occurred, and whether or not XSS-11 visited any non-US space objects, because the US military did not publish any positional information for the XSS-11 while on orbit.

Minotaur image
Image of a Minotaur upper stage taken by XSS-11 from a distance of approximately 500 m. Image credit: AFRL.

The RPO conducted by Cosmos 2499 and Cosmos 2504 appear, based on the publicly available evidence, to be very similar to the RPO of the American XSS-10 and the Chinese SJ-12, and somewhat similar to DART. Four of the five cases (XSS-10, SJ-12, Cosmos 2499, and Cosmos 2504) involved a drawn-out series of maneuvers to slowly approach and rendezvous with another object, with DART being the exception. DART attempted to rendezvous with MUBLCOM on the same day it was launched.

There is also a similarity between GSO maneuvering of Luch and the activities of a US military satellite in GSO. Officially designated USA 207, the satellite was launched on September 8, 2009, under unusual secrecy. Normally, at least the federal agency sponsoring classified US national security satellites is made public, even when it’s the National Reconnaissance Office (NRO), an organization whose existence was not declassified until 1992. But in the case of USA 207, no federal agency was provided, and the launch was not given a NRO launch designator. Some details did emerge with the release of the official mission patch, which referred to the satellite as PAN, an acronym for Palladium at Night (see “PAN’s labyrinth”, The Space Review, August 24, 2009). After launch, more details emerged that the satellite was built by Lockheed Martin for an unnamed government customer and was based on a commercial communications satellite bus.

Like most US military satellites, there are no details of PAN’s orbit in the Space Track catalog maintained by the US military. However, it has been consistently tracked by hobbyist observers. Based on their observations, PAN was originally located at 33 degrees east longitude, but has moved several times to different orbital slots over the Middle East. According to one observer, PAN moved to 38 degrees east in May 2010, 49 east in December 2010, 44.9 east in the spring of 2011, 39.1 east in the summer of 2011, 52.5 east by January 2012, back to 38 degree east in May 2012, 42.5 degrees east in December 2012, and 47.9 east in May 2013. It has remained at 47.9 east for the last two years and has not maneuvered again, except for the stationkeeping required to maintain that slot.

While PAN has maneuvered often to different GSO slots, it is not known to have purposefully maneuvered close to another space object. However, there are other US military satellites programs that have done so in GSO.

The actual nature of PAN’s mission is unknown, although there has been some speculation. Satellite observer Greg Roberts detected it emitting UHF radio signals that were unique to the US Navy’s Ultra High Frequency Follow-on (UFO) spacecraft. The UFO satellites are used to communicate with ships at sea, and the speculation is that PAN was a quick-turnaround satellite used to fill in a gap between the older UFO satellites and the Multi-User Objective System (MUOS) satellites slated to replace them. However, both UFO and MUOS are acknowledged military satellite programs, leading some to suspect that PAN had other missions. These could include a SIGINT role, or potentially in support of data relay for US intelligence agencies.

On September 16, 2014, the United States launched what many observers believe to be the follow-on to PAN. Named CLIO in the press and officially designated USA 257, the mission bore many similarities to PAN. CLIO was also built by Lockheed Martin, made use of the same A2100A commercial communications satellite bus, and was developed for an unnamed US government customer. While CLIO has not been as well tracked by observers as PAN, indications are that it has also maneuvered between orbits slots multiple times.

While PAN has maneuvered often to different GSO slots, it is not known to have purposefully maneuvered close to another space object. However, there are other US military satellites programs that have done so in GSO. The earliest one that is believed to have conducted RPO in GSO is a still heavily classified satellite reportedly called Prowler. Based on publicly-available data, satellite observer Ted Molczan concluded that Prowler was secretly launched from a Space Shuttle mission in 1990, and matched the description given in a 2004 NBC news article about a classified US government satellite program that had run afoul of Congress. The satellite had reportedly maneuvered close to multiple Russian GSO satellites to collect intelligence on their characteristics and capabilities, and utilized stealth technologies to remain undetected by Russian optical space surveillance systems. To this day, the US has never officially acknowledge the existence of Prowler, and lists it as an extra rocket body from the shuttle launch in its public catalog. The satellite is not registered with the UN.

While Prowler is thought to have been decommissioned in around 1998, it was followed by programs designed for similar missions. In 2006, the US Air Force launched two small satellites into GSO. Officially designated as Micro-satellite Technology Experiment (MiTEx), the two satellites were designated USA 187 and USA 188. Their official mission was to identify, integrate, test, and evaluate small satellite technologies to support and enhance future US space missions. Observers speculated that the MiTEx satellites would be conducting RPO in GSO (see “Mysterious microsatellites in GEO: is MiTEx a possible anti-satellite capability demonstration?”, The Space Review, July 31, 2006). In 2009, news reports revealed that they had been used to conduct “flybys” of the US early warning satellite DSP 23, which had mysteriously failed on orbit shortly after launch. Observations from hobbyists noted that the two MiTEx satellite maneuvered from their parking slots in GSO to drift towards the location of DSP 23, passing it around December 23, 2009, and January 1, 2010.

On February 21, 2014, Air Force Space Command publicly revealed the existence of another program to conduct similar inspections in the GEO region using RPO. The new program, dubbed the GEO Space Situational Awareness Program (GSSAP), would deploy two pairs of small satellites to near-GEO orbits. The satellites would be placed at altitudes slightly above and below the GSO belt, allowing them to drift east and west and provide close inspections of objects in the GEO region. The official Air Force fact sheet states that the GSSAP satellites would be able to conduct RPO of “resident space objects of interest.” The artist’s depiction of GSSAP bears a resemblance to the form factor of the XSS-11.

GSSAP satellites
While Russia is experimenting with rendezvous and proximity operations missions, the US military has been doing such missions for years, including the recent GSSAP spacecraft. (credit: US Air Force)

The Air Force also announced that the first two GSSAP satellite would launch along with a satellite from another RPO program, the Automated Navigation and Guidance Experiment for Local Space (ANGELS) Program. The goal of ANGELS is to provide a clearer picture of the local area around important US national security satellites in GSO. The first ANGELS satellite would stay attached to the Delta IV upper stage while it placed the first GSSAP pair into GSO and conducts a disposal maneuver to place it a few hundred kilometers above GSO. At that point, ANGELS would detach from the upper stage and conduct a series of RPO maneuvers to close within a few kilometers.

The first two GSSAP satellites and ANGELS were launched into orbit on July 23, 2014, and assigned the official designators of USA 253, USA 254, and USA 255. As is usually the case with US military satellites, the US military has not published any orbital elements for them, nor provided information on where they are located. However, on September, 18, 2015, General John E. Hyten, Commander of US Air Force Space Command, remarked at a public forum that the two GSSAP satellites had been “pressed into early service” to provide information to an un-named customer. According to General Hyten, the two satellites provided what he deemed “eye-watering” pictures of one or more objects in GSO.

It is more likely that the main US concern is with the implications of Russia (and China) developing RPO capabilities for the ability of the United States to maintain its dominance in space.

Ultimately, it is clear that the recent Russian RPO activities in both LEO and GEO are, at least from the outside, not very different from American RPO activities in LEO and GEO over the last decade. Furthermore, through programs such as XSS-11 and ANGELS, the United States has demonstrated far more advanced RPO technologies and capabilities than Russia or China. Conducting RPO at an altitude of more than 36,000 kilometers (22,000 miles), as ANGELS plans to do, or among active GSO satellites, as with GSSAP, is in some ways more challenging than doing so in LEO. The US Air Force itself has talked publicly about the immense challenges of the precision command and control needed to ensure that such activities occur safely.

The similarity between the Russian RPO and US RPO activities raises the question of why Russian RPO activities have created such concern in the US national security community. Part of this concern could be the heritage of some of these programs. The Rockot booster used to place Cosmos 2499 and Cosmos 2504 into orbit began life in the mid-1980s as part of a Soviet co-orbital ASAT program known as Naryad. The Naryad system utilized a rocket based on the UR-100N ICBM (NATO designation SS-19 Stiletto) that was fitted with a powerful upper stage that could place one or more kill vehicles into orbits as high as 40,000 kilometers (24,850 miles), allowing them to independently target and home in on multiple target satellites.

After the demise of the Soviet Union in 1991, the Naryad system was repurposed as the Rockot SLV and the Briz upper stage. The first orbital launch of the Rockot placed a small amateur radio satellite, Radio-ROSTO, into an orbit of 1,900 by 2,145 kilometers (1,180 by 1,332 miles) orbit in 1994. Radio-ROSTO was based on the Strela-1M military communications satellite, a predecessor of the Rodnik satellites launched with Cosmos 2499, further deepening the potential perceived link between the original Naryad program and the current RPO activities.

Another possibility is that the United States has specific classified intelligence that indicates the activities are actually part of Russian and Chinese counterspace programs. However, if that is the case, it creates a significant public diplomacy and political challenge for the US government on how to characterize these Russian and Chinese activities as “bad” or “irresponsible” while not hindering similar US activities. This is a similar challenge to what the United States faces in the cyber world.

It is more likely that the main US concern is with the implications of Russia (and China) developing RPO capabilities for the ability of the United States to maintain its dominance in space. The United States has long enjoyed a significant lead in space capabilities over every other nation in terms of both numbers of satellites and the qualitative capabilities that they deliver. The fact that other nations, and in particular those who some consider to be future adversaries, are beginning to close the gap is probably very troubling for US commanders who have always been ten steps (or more) ahead. The recent Russian and Chinese RPO activities suggest that these countries are working on developing some of the same capabilities as the United States, including the ability to do close up inspection of, and possibly cause physical harm to, satellites in orbit. Coupled with the US reliance on its space capabilities, this is a significant change for the US national security space community to deal with.

The specific capability that is likely feared the most is that small satellite RPO will give Russia and China the ability to deploy so-called “space mines.” Space mines have long been theorized as small co-orbital ASATs that can maneuver into an orbit that brings them close to the target satellite. The mines can stay in this position for extended periods of time and, when necessary, can be maneuvered close enough to the target to deploy a conventional explosive or nuclear detonation that can destroy the target or cause significant damage. Against larger, more expensive satellites, space mines were theorized to be a useful and hard-to-counter ASAT capability that was a direct outcome of developing RPO technology. This is partly because they are harder to detect, and partly because their pre-positioning means they could act much faster than a direct ascent ASAT launched from the ground, particularly against GSO targets. One US strategist concluded in the mid-1980s that “once the Soviets achieve a satellite-to-satellite docking capability, they also automatically achieve a conventional ASAT capability.” It is likely the same conclusion is being made about Russian and Chinese RPO activities today by US strategists, and perhaps vice versa about the United States by Russian and Chinese strategists.

page 3: policy implications and recommendations >>