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As of February 2022, the catalogue of space objects in the geostationary regime consists of about 5000 objects. Although not all of them are visible from a single telescope station, it is not possible to observe all of them in a single night. Together with the search for new objects, the task of catalogue maintenance becomes challenging. With the telescope network SMARTnet, we test different strategies to optimise planning of observation times of the individual stations. One strategy is called Optimal Catalog Maintenance and Survey Tasking (OMST) and tries to achieve the maximum number of detections with the minimum amount of viewing directions in sum of all involved telescopes. The strategy may be applied to a single telescope as well as to a sensor network. In the latter case, an optimisation trade-off is made in terms of sensor availability, probability of detection including the local viewing conditions and sensor capabilities. SMARTnet’s telescope stations are located on the Southern hemisphere utilising winter nights during the observation period. The observation plan is calculated for each station at the German Aerospace Centre (DLR) and distributed to the telescope stations. Conditions permitting, each plan is executed as complete as possible. Afterwards, the observation tracklets are analysed. Using subsequent nights, the performance of single object tasking – also called classical tasking – and OMST tasking is evaluated. Evaluation criteria are the comparison between the predicted and actually successfully observed objects, the total number of successfully observed objects and the rate between already catalogued objects, for which the tasking was run and previously uncatalogued objects.

Operation of satellites and research of their orbital regions depend on both modelling e. g. of the environment and data banks consisting of objects with preferably high accuracy ephemerides and, if possible, completeness of the number of objects in this region. If concentrating on the geostationary regime, it is assumed that a detection size of an object of 30cm or larger is sufficient for the aforementioned topics. It is of international interest to exchange and access this data on a low cost basis. For this reason, SMARTnet™ was developed, allowing for interchanging data, especially tracklets, within the community of sensor owners or sensor operators on a no exchange of funds basis. The first contributors to SMARTnet™ are operating optical telescopes and produce tracklets. In this context, a tracklet is a series of the angle pair right ascension and declination including the corresponding epoch of a single object. In 2017, SMARTnet™ was opened for international co-operations. The main objective of SMARTnet™ is the exchange of tracklets, allowing for each participating entity to develop own catalogues, own algorithms, and own products. Since then, Applied Defense Solutions has joined SMARTnet™ and is the first Partner. A basic statistic of the data available through SMARTnet™ is shown as well as first results with respect to a first data bank of objects, which can be derived from this data.

Operation of satellites and research of their orbital regions depend on both modelling e. g. of the environment and data banks consisting of objects with preferably high accuracy ephemerides and, if possible, completeness of the number of objects in this r egion. If concentrating on the geostationary regime, it is assumed that a detection size of an object of 30cm or larger is sufficient for the aforementioned topics. It is of international interest to exchange and access this data on a low cost basis. For this reason, SMARTnet™ was developed, allowing for interchanging data, especially tracklets, within the community of sensor owners or sensor operators on a no exchange of funds basis. The first contributors to SMARTnet™ are operating optical telescopes and produce tracklets. In this context, a tracklet is a series of the angle pair right ascension and declination including the corresponding epoch of a single object. In 2017, SMARTnet™ was opened for international cooperations. The main objective of SMARTnet™ is the exchange of tracklets, allowing for each participating entity to develop own catalogues, own algorithms, and own products. Since then, Applied Defense Solutions has joined SMARTnet™ and is the first Partner. A basic statistic of the data available through SMARTnet™ is shown as well as first results with respect to a first data bank of objects, which can be derived from this data.

One of the main aim of the scientific research in the space debris field is the characterization of the space debris population. Questions like: how many debris objects are there, where are they, how big are they, what are they made of, and therefore how their population will evolve with time could not be answered without the help of measurements acquired with ground-based sensors. The Swiss Optical Ground Station and Geodynamics Observatory Zimmerwald (SwissOGS), owned and operated by the Astronomical Institute of the University of Bern (AIUB), has performed astronomical observations over the last 60 years. First, performing “classical” astronomical observations focusing on sky surveys to detect supernovae, minor planets, and comets; then, especially in the last 40 years, also performing satellite laser ranging measurements and passive optical observations to discover and characterize space debris. In order to be autonomous in the discovery, the cataloguing, and the characterization of the space debris and to still fulfill the duties within the satellite laser ranging community, substantial extension of the SwissOGS sensor suite was needed. First, the historical Schmidt-Cassegrain telescope was substituted with the new 0.8-meter Zimmerwald Multiple Applications Instrument (ZimMAIN); then, two new domes were built and equipped with state of the art telescopes: the Zimmerwald Twin Widefield Instrument and the Zimmerwald Network Telescope (ZimTWIN and ZimNET, respectively). Nonetheless, the capabilities of the “old” telescopes are still under development and improvement. In this paper, we will present the new capabilities of the SwissOGS for both, space debris and NEO research, showing the main aims and activities which can be performed through the use of the newly implemented telescope systems. Then first results and performance figures of the new telescopes will be shown and finally, we will report on the current status and the recent improvements of the existing telescopes.

Operation of geostationary satellites and research of the geostationary region depend on both modelling e. g. of the environment and data banks consisting of objects with preferably high accuracy ephemerides and, if possible, completeness of the number of objects in this region. Of course, due to physical reasons, not all objects are detectable, but for now it is assumed that an object size of 30cm or larger is sufficient for the aforementioned topics. It is of international interest to exchange and access this data on a low cost basis. For this reason, SMARTnetTM was started, allowing for interchanging data, especially tracklets, within the community of telescope owners or telescope operators on a no exchange of funds basis. In this context, a tracklet is a series of the angle pair right ascension and declination including the corresponding epoch of the same object. Over one year ago, SMARTnetTM was opened for international co-operations. The main objective of SMARTnetTM is the exchange of tracklets, allowing for each participating entity to develop own catalogues, own algorithms, and own products. In this paper, the consortium, consisting of the Astronomical Institute of the University of Bern (AIUB) and the German Space Operation Center (GSOC) at DLR, is presenting the current partners of SMARTnetTM, statistics of data collected as well as results like e. g. tracklet correlation. Furthermore, an outlook of future contributions is given.

Situation awareness of objects in the geostationary regime is of great interest for collision avoidance by active satellites as well as for scientific research on the space debris population and their evolution over time. As the number of satellite operators and researches in this field is large, it makes sense to set up a sensor network with multiple entities to combine all available sensor measurements for a comprehensive situational picture. This will allow for cost sharing and optimising observation strategies to gain as much information as possible about the desired objects. Therefore, the German Space Operation Center, GSOC, together with the Astronomical Institute of the University of Bern, AIUB, are setting up a global optical sensor network called SMARTnet(TM): the Small Aperture Robotic Telescope Network. The main objective is the free exchange of all information gathered, mainly in form of tracklet observations, within all partners involved. In this paper, the operation of the first half year of SMARTnet is presented. Results on object correlation, loss of objects of the catalogue, statistics on observable nights as well as accuracy on orbit determination is shown. Furthermore, an outlook on future stations is given. Additionally, the partnering system is introduced including the possibility for other entities to join the network and it is shown how tracklets are exchanged.

Requirements for the automation of an SLR system may stem from different applications. In Zimmerwald the main goals are in particular the automation of the routine ILRS observations, the Space Debris observations, the interleaved SLR and optical observations, as well as experimental measurements (e.g. time transfer, multi-static space debris observations, etc.). An overview will be provided on the different components related to automation, including the hardware, the hardware independent and hardware dependent software parts, and safety related issues. Different strategies of automation are shown for two of our measurements systems. Firstly for the ZIMLAT legacy SLR system which is by now 20 years old and requires replacement of old hardware and electronics components and porting of software onto new operating systems and computer hardware. Secondly we will present the development of a new measurement system, originally designed for space debris observation, based on completely new hardware (telescope and mount). This system is currently validated and its tracking performance for LEO objects is being optimized and characterized.

Space debris in geostationary orbits may be detected with optical telescopes when the objects are illuminated by the Sun. The advantage compared to Radar can be found in the illumination: radar illuminates the objects and thus the detection sensitivity depletest proportional to the fourth power of the d istance. The German Space Operation Center, GSOC, together with the Astronomical Institute of the University of Bern, AIUB, are setting up a telescope system called SMARTnet to demonstrate the capability of performing geostationary surveillance. Such a telescope system will consist of two telescopes on one mount: a smaller telescope with an aperture of 20cm will serve for fast survey while the larger one, a telescope with an aperture of 50cm, will be used for follow-up observations. The telescopes will be operated by GSOC from Oberpfaffenhofen by the internal monitoring and control system called SMARTnetMAC. The observation plan will be generated by MARTnetPlanning seven days in advance by applying an optimized planning scheduler, taking into account fault time like cloudy nights, priority of objects etc. From each picture taken, stars will be identified and everything not being a star is treated as a possible object. If the same object can be identified on multiple pictures within a short time span, the trace is called a tracklet. In the next step, several tracklets will be correlated to identify individual objects, ephemeris data for these objects are generated and catalogued . This will allow for services like collision avoidance to ensure safe operations for GSOC’s satellites. The complete data processing chain is handled by BACARDI, the backbone catalogue of relational debris information and is presented as a poster.

During the last years the use of tracking cameras for SLR observations became less important due to the high accuracy of the predicted orbits. Upcoming new targets like satellites in eccentric orbits and space debris objects, however, require tracking cameras again. In 2013 the interline CCD camera was replaced at the Zimmerwald Observatory with a so called scientific CMOS camera. This technology promises a better performance for this application than all kinds of CCD cameras. After the comparison of the different technologies the focus will be on the integration in the Zimmerwald SLR system.

The Zimmerwald SLR station is operated in a monostatic mode with 532nm laser pulses emitted at adjustable frequencies of 90-110Hz with energies slightly less than 10mJ. A rotating shutter protects the CSPAD receiver from the backscatter of the transmit beam. These systems are located below the telescope in an operator room housed within the observatory building with the laser system located in a separated, air-conditioned part of the room. All hardware components may be automatically accessed by the control software and from remote if required. Thanks to the fully automatic and remotely controllable SLR operations, the Zimmerwald station is one of the most productive stations in the ILRS network. Key characteristics of the hardware are shown. Specialities like the tracking of the full GLONASS constellation, one-way ranging to the Lunar Reconnaissance Orbiter, and photon reception from bi-static experiments with the Graz SLR station are highlighted as well.