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A publication of Technical Editor Robert C. Reynolds NASA Johnson Space Center Managing Editor Houston, Texas 77058 Cindi A. Karpiuk October - December 1997 Volume 2, Issue 4. NEWS Naval Space Operations Center Finds New Evidence of Debris Separations from Three Spacecraft N. Johnson traced to Transit 10 (1965-109A, Satellite to the design or materials selection of the Number 1864) which was also involved in a vehicles. Transit spacecraft are likely to During July and August personnel of the Naval late 1996 release. The debris was found in exhibit multiple events, whereas the Vostok Space Operations Center, which serves as the early August, but orbital analysis could not upper stages appear limited to a single event. alternate Space Control Center for the US determine when it had been created. The two However, only a small percentage of vehicles Space Surveillance Network, detected five new debris pieces remain in orbits very similar to in these families are involved in anomalous debris from three spacecraft, each more than 15 that of the parent. events. years old. The causes of these "anomalous events", which involve very low separation In late August the NOAA 7 spacecraft (1981- A newly cataloged debris (Satellite Number velocities, remain a mystery, although material 59A, Satellite Number 12553) spawned at 24893) from the Kosmos 1939 Vostok upper degradation or small particle impacts are least three new debris, one of which was stage (Satellite Number 19046) had actually probable agents. cataloged as Satellite Number 24935. The been tracked by the SSN for nearly five years, debris appear to have been released, perhaps at and a sister debris remains in track but not yet At least six polar-orbiting Transit satellites the same time, during 23-24 August. The cataloged. Normally, the total number of debris have generated debris more than 20 years after spacecraft had previously released two debris released by a satellite does not exceed six, launch. Sometime between 20 and 23 July, a on 26 July 1993, three years after spacecraft although in two cases, Snapshot (1965-27A) single object was released from Transit 17 deactivation, but both decayed the following and COBE (1989-89A), the debris counts were (1967-92A, Satellite Number 2965), marking year. 50 or more. To date, the number of orbital at least the fourth such event for this spacecraft debris produced during anomalous events since 1981. The last previous debris release The mechanism behind the generation of accounts for only 2% of the total cataloged was in December 1996 (see Orbital Debris anomalous event debris large enough to be satellite population, but this figure could Quarterly News, January 1997). The five tracked by ground-based sensors remains increase as the large resident space object debris previously cataloged with this source all poorly understood. Some space objects, e.g., population increases and ages. exhibited high area-to-mass ratios and have U.S. Transit spacecraft and Soviet Vostok decayed from orbit. upper stages, seem predisposed to such Another newly discovered debris has been incidents and, therefore, are probably related Inside... Intentional LEO Spacecraft Breakup in September ..............................................2 Orbital Debris as Detected on Exposed Spacecraft ............................................... 3 Launch Record for Last Quarter ............................................................................11 Orbital Box Score .....................................................................................................12 1 The Orbital Debris Quarterly News NEWS, Continued Intentional LEO Spacecraft Breakup in September N. Johnson event, the NASA Johnson Space Center Space Kosmos 2343 had just completed a four-month Science Branch initiated an immediate threat On 16 September the Russian Military Space mission when it brokeup at 2208 GMT while assessment of the debris cloud with respect to Forces destroyed a reconnaissance spacecraft passing 230 km over the Kamchatka pennisula. the Mir space station. Assuming a complete in low Earth orbit, producing a cloud of short- Three of the five previous vehicles (Kosmos fragmentation of the estimated 6500 kg dry lived debris. Kosmos 2343, launched on 15 2101, 2163, and 2225) were destroyed at mass of Kosmos 2343, a debris cloud of 1 mm May 1997, was the sixth in a new generation of virtually the same location. During the next 48 and larger particles was simulated and military spacecraft which debuted in 1989. hours the U.S. Space Surveillance Network propagated for a week. Even though some Unlike other reconnaissance spacecraft which (SSN) was able to characterize the orbits of 32 tracked debris possibly came within 20 km of occasionally have been destroyed when debris, three with apogees near 900 km Mir, 70% of the threat had passed after the first malfunctions prevented planned reentry indicating ejection velocities on the order of 24 hours. No tracked debris triggered a operations (14 such incidents during 1964- 200 m/s. collision warning, i.e., predicted penetration 1993), this new class of vehicles appear to into a 4 km by 10 km by 4 km box centered employ self-destruction as a standard end-of- Although half of the debris (those ejected in a around Mir. An assessment was also made to life operating procedure. Previous missions of retrograde direction) reenter very quickly, determine if any unacceptable risk might be this type include Kosmos 2031, Kosmos 2101, historically as manay as 180 debris have been posed to the forthcoming Space Shuttle Kosmos 2163, Kosmos 2225, and Kosmos detected by the SSN. Consequently, upon mission, STS-86 on 25 September, to Mir, but 2262. being notified of the Kosmos 2343 breakup no significant hazard was found. Detection of Very Small Debris With Haystack G. Stansbery recent impacts on the Space Shuttle have to improve the sensitivity of Haystack. NASA suggested that the population of smaller debris has contracted with MIT Lincoln Laboratory to NASA/JSC has been using the Haystack radar (0.1-0.2 cm diameter) has recently increased. perform a study to select the optimum radar under a Memorandum of Agreement (MOA) At its current sensitivity, Haystack has detected parameters with the goal of detecting 0.25 cm with the U.S. Air Force to statistically no such increase. It is possible to “tweek” the diameter debris at Space Shuttle altitudes and characterize the orbital debris population in low pulselength, pulse repetition frequency (PRF), 0.5 cm diameter debris at 1000 km altitude. earth orbit (LEO) for debris sizes between and the number of pulses integrated over a Further, they will implement and test the about 0.6 - 30 cm diameter since 1990. Several limited range window at Space Shuttle altitudes chosen parameters to ensure data validity. Meeting Report IAA Subcommittee on Space Debris The International Academy of Astronautics one of the debris sessions at this Congress be problem for many years and issued the IAA (IAA) Subcommittee on Space Debris met in devoted to satellite constellations, perhaps in a Position Paper on Orbital Debris in 1993. Be- Turin in conjunction with the International As- joint session with one of the spacecraft commit- ing concerned about this problem which causes tronautical Federation (IAF) Congress. The tees. The Aerospace Corporation also presented a growing threat for the future of space flight, meeting was chaired by Professor Walter Flury an overview of its recently established Center the IAA initiated a study to be performed under and was attended by 20 members. for Orbital and Reentry Debris Studies. the supervision of its Committee on Safety, Rescue, and Quality. The objectives were to The primary topic of discussion at the meeting Abstract for the Space Debris Mitigation Paper: elaborate on the need and urgency for mitiga- was a draft of a debris mitigation paper that is tion actions and to identify implementation being prepared by the subcommittee for the The International Academy of Astronautics methods. Since the issue is so complex, it may Scientific and Technical Subcommittee of the (IAA) is glad to be given the opportunity to not be possible to come to a final solution in UN Committee on Peaceful Uses of Outer address the Scientific and Technical Subcom- due time. Therefore, some preliminary guide- Space (UNCOPUOS). An abstract of this paper mittee of the United Nations’ Committee on the lines, codes of conduct, or principles address- appears below. Peaceful uses of Outer Space on the important ing the minimization or avoidance of space matter of space debris. Our allocution will fo- debris could be proposed as an interim solution. The 1999 IAF meeting, to be held in Amster- cus on this year’s topic—space debris mitiga- dam, was also discussed. It was proposed that tion. IAA has been aware of the space debris 2 The Orbital Debris Quarterly News Project Reviews Orbital Debris as Detected on Exposed Spacecraft R.P. Bernhard, E.L. Christiansen in LEO resulting in such collisions could be between the Inconel Thermal Spring and the derived. Foam RTV Seal material (figure 1). Traces of Several projects of major importance to Aluminum were also detected on tape pull understanding of the particulate population in With the advent of Space Shuttle flights in the samples taken from the penetration in the LEO were derived from Space Transportation 1980’s a number of Orbiter structures have Inconel thermal spring. Calculations show System (STS) flights in 1984. Mission STS- received impact craters large enough to that the colliding orbital debris particle was 41C retrieved about 3 square meters of Solar warrant repair. STS-7, flown in June of 1983, approximately 1.0mm in diameter. Maximum Satellite hardware after being sustained significant damage to the right exposed 4.15 years in LEO, and deployed the middle window from a Aluminum Residues 2 3.4mm 130 meter Long Duration Exposure Facility Earth-orbiting spacecraft RTV Seal (2.54mm) (LDEF) satellite. In November 1984 STS-51A paint particle. To date Inconel 0.2m m RTV 0.15mm retrieved the PALAPA-B2 satellite after 9 several thousand impacts Al 2024 2.4mm x 1.7m m 0.3m m RTV 0.15mm months in space.