National Aeronautics and Space Administration Orbital Debris Quarterly News Volume 15, Issue 3 July 2011 International Space Station Again Inside... Dodges Debris For the fifth time in 2 1/2 years, the during 2 April if no action was taken. Additional New Evidence of International Space Station (ISS) had to execute a tracking data was acquired, and new predictions Particle Impact on collision avoidance maneuver in early April to ensure were performed, leading to even higher calculated Jason-1 Spacecraft 2 a safe miss distance for a piece of orbital debris. As values of probability of collision. A plan was Reentry of U.S. solar activity increases during the next few years, the developed to use the European Automated Transfer Rocket Stage Over frequency of ISS collision avoidance might increase Vehicle 2 (ATV-2), which had docked at the aft end South America 3 as many hundreds of resident space objects drift of the ISS complex on 24 February, to conduct a down through the ISS orbital regime. small evasive maneuver. The burn, which lasted 50th Anniversary The subject of concern in late March 2011 3 minutes and 18 seconds, was executed early 2 April of First On-Orbit was a fragment from Cosmos 2251, the Russian (GMT), imparting a change in velocity to ISS of only Satellite communications satellite which had accidentally 0.5 meters per second. Fragmentation 3 collided with the U.S. Iridium 33 communications This maneuver was the 12th collision avoidance satellite in February 2009, producing more than maneuver conducted by ISS since October 1999. MMOD Impacts on 2000 large debris. Designated as Satellite Number ISS Airlock Shields 5 continued on page 2 34443 in the U.S. Satellite A Note on Active Catalog (International Debris Removal 7 Designator 1993-036SL), 800 the fragment had Meeting Report 9 an apparent size of 10-15 cm. Initially 700 Space Missions thrown into a moderately and Satellite elliptical orbit by the 2009 Debris Apogee Box Score 10 600 collision, the debris had Debris Perigee spent essentially its entire km) orbital lifetime passing ( 500 e through the orbital ud t regime of the ISS many lti A times each day (Figure 1). 400 On 30 March a collision risk in excess of 1 in 10,000 (the 300 Orbital regime of International Space Station threshold above which collision avoidance 200 maneuvers are normally 2009 2009.5 2010 2010.5 2011 2011.5 A publication of dictated) was predicted Time the NASA Orbital to occur on three Debris Program Office successive revolutions Figure 1. Orbital decay of debris which caused the ISS collision avoidance maneuver. Orbital Debris Quarterly News ISS Dodges Debris continued from page 1 Although maneuvers prior to 2008 had been stage (18 July 2009), and from the NASA UARS was available to prepare for and to conduct a required to evade intact spacecraft or launch spacecraft (26 October 2010). collision avoidance maneuver. As a precaution, vehicle stages, the last five maneuvers were In late June another close approach by a on 28 June the six members of the ISS crew caused by decaying fragmentation debris. The tracked, but uncataloged, debris was identified, retreated to the two attendant Soyuz transport four events prior to 2011 involved debris from leading to a calculated probability of collision ships to be ready to undock and return to Earth the Russian Cosmos 2421 spacecraft (27 August on the order of 1 in 360, with a miss distance of should a collision occur. In the end, the debris 2008), from a Chinese launch vehicle stage 725 m. However, due to the rapidly changing passed the ISS without further incident, and the (22 March 2009), from a Russian launch vehicle elliptical orbit of the debris, insufficient time crew returned to their normal duties. ♦ New Evidence of Particle Impact on Jason-1 Spacecraft Nine years after the event, new analyses left solar array from above on the segment Subsequent orbital analyses by SSN indicate that the joint U.S.-French spacecraft closest to the main structure (Figure 1). The specialists indicated that the debris indeed Jason-1 was struck by a high-speed particle attitude upset was accompanied by a temporary originated from Jason-1 on 16 March 2002, only three months after launch. Although at (a few hours) electrical current disturbance. although the objects were not officially least two detectable debris were generated, Although not linked, at the time, to the cataloged until 2009 and 2011 as Satellite the spacecraft continues to this day to provide spacecraft anomaly, the U.S. Space Surveillance Numbers 35414 and 37379. valuable data on the topography of the Earth’s Network (SSN) soon detected two new objects It is not possible to discern whether oceans. in orbits slightly lower than that of Jason-1 the impacting particle was natural or man- Following a launch from Vandenberg AFB (Figure 2). The debris were determined to have made. At the altitude of Jason-1, the orbital in California by a Delta 2 rocket on 7 December been ejected from the spacecraft with moderate debris population is relatively slight. Jason-1 2001, Jason-1 (International Designator 2001- velocities of 24 and 46 meters per second, experienced a second anomaly (including 055A, U.S. Satellite Number 26997) quickly respectively. Both debris are also small (less temporary loss of command) in 2005, but there reached its operational orbit of 1336 km with an than 20 cm) and exhibit relatively large area-to- is no evidence that the event was caused by a inclination of 66 degrees, where it coordinated mass ratios (> 2 m2/kg). particle impact. ♦ operations with the earlier U.S.-French spacecraft TOPEX/Poseidon. However, on 16 March 2002, spacecraft controllers noted 113.0 a distinct attitude upset of the vehicle. A detailed study of the spacecraft’s perturbations Impact Event: 16 March 2002 suggested that a small particle had struck the 112.5 Jason-1 Spacecraft 112.0 ) in 111.5 (m od 111.0 Jason-1 Debris #1 al Peri 110.5 bit Or 110.0 Jason-1 Debris #2 109.5 109.0 2011 2002 2003 2004 2005 2006 2007 2008 2009 2010 2012 Time Figure 1. Jason-1 spacecraft configuration. Figure 2. Orbital history of Jason-1 and two debris released in March 2002. 2 www.orbitaldebris.jsc.nasa.gov Reentry of U.S. Rocket Stage over South America In early March 2011, the titanium casing of SRM, Navstar 53 inserted itself into the desired a solid rocket motor (SRM) landed harmlessly operational orbit, leaving the ~230-kg Delta 2 in northern Uruguay. A remnant of the third third stage to gradually fall back to Earth. stage of a U.S. Delta 2 rocket which had been in Reentry began over the Pacific Ocean as orbit for 7 years, the former orbital debris had the stage, known as a Payload Assist Module or a diameter of 1.2 m and an estimated mass of PAM-D, approached South America. Traveling about 50 kg upon impact. over Chile and Argentina, the STAR-48B SRM The Delta 2 was launched on 21 December casing, sans nozzle, came to rest near the town 2003 on a successful mission to place a new of Artigas, Uruguay, at about 10:00 pm local Global Positioning Satellite (GPS), Navstar 53, time on 2 March (Figure 1). This was the fourth into a circular, semi-synchronous orbit. The report in 10 years of a STAR-48B casing being third stage of the launch vehicle (International found after reentry. Earlier recoveries occurred Designator 2003-058C, U.S. Satellite Number in Saudi Arabia (2001), Argentina (2004), and 28131) lifted the spacecraft from a low Earth Thailand (2005) (see ODQN, April 2001, p. 1; orbit into a highly elliptical transfer orbit of April 2004, p. 1; and April 2005, p. 2). All four Figure 1. STAR-48B motor casing which landed approximately 180 km by 20,300 km with an SRMs had supported GPS missions. ♦ in Uruguay during the evening of 2 March 2011 inclination of 39 degrees. Using a separate (local time). PROJECT REVIEW Fiftieth Anniversary of First On-Orbit Satellite Fragmentation N. JOHNSON orbit (LEO) region with some of the fragments other breakup events.] Due to the high altitude On 29 June 1961, a U.S. Ablestar upper reaching to altitudes above 2000 km. of the event, 60% of these debris (176 in all) stage exploded into nearly 300 large pieces, Despite the rudimentary nature of space remain in Earth orbit today (Figure 3). overwhelming the then official total Earth surveillance sensors in the early 1960s, this A thorough orbital population of only 54 objects. The 50th satellite breakup remains one of the best investigation continued on page 4 anniversary of this seminal event was marked documented since the vehicle was being into the possible this year with both reflection and optimism: observed with both radio and optical means at causes for the reflection on the more than 200 known the time of the event. From a southeasterly catastrophic event satellite fragmentations which followed and launch from Cape Canaveral, Florida (Figure 1), was immediately optimism that current space vehicle designs the Ablestar stage led the Transit 4A and the still- undertaken. A and operations will continue to curtail such joined Injun 1 and Solrad 3 satellites as the trio preliminary report accidental occurrences in the future. passed for the first time over the western United identified two basic The Ablestar stage (International States. At 0608 GMT a Baker-Nunn camera in mechanisms which Designator 1961-015C [aka 1961-Omicron 3], Organ Pass, New Mexico, clearly photographed might have caused U.S.