SJR is a measure of scientific influence of journals that accounts for both the number of citations received by a journal and the importance or prestige of the journals where such citations come from It measures the scientific influence of the average article in a journal, it expresses how central to the global scientific discussion an average article of the journal is. It is based on the idea that 'all citations are not created equal'. The SJR is a size-independent prestige indicator that ranks journals by their 'average prestige per article'. SCImago Journal Rank (SJR) 2022: 0.342 ℹ SCImago Journal Rank (SJR): The Journal Impact Factor is the average number of times articles from the journal published in the past two years have been cited in the Journal Citation Reports year.ĬiteScore is the number of citations received by a journal in one year to documents published in the three previous years, divided by the number of documents indexed in Scopus published in those same three years. The Impact Factor itself is based only on Web of Science Core Collection citation data from the last three years and thus reflects only recent impact. This is calculated differently from the Journal Impact Factor, so it is not simply an average of the Impact Factors in the time period. Thus, the impact factor of a journal is calculated by dividing the number of current year citations to the source items published in that journal during the previous two years.ĥ-Year Impact Factor: 1.944 ℹ 5-Year Impact Factor:Ī 5-Year Impact Factor shows the long-term citation trend for a journal. The annual JCR impact factor is a ratio between citations and recent citable items published. The impact factor is one of these it is a measure of the frequency with which the “average article” in a journal has been cited in a particular year or period. The JCR provides quantitative tools for ranking, evaluating, categorizing, and comparing journals. In-depth reports on the communication subsystems of many of the JPL-led missions with which the DSN has communicated are available at the the DESCANSO Design and Performance summary series page.Impact Factor (JCR) 2021: 2.299 ℹ Impact Factor (JCR): More information is also available at the Canberra Deep Space Communications Center and the Madrid Deep Space Communications Center. General information on the DSN is available at the DSN Website. In some instances, testing of hardware that was customized for a long-finished mission may cause a ‘phantom’ spacecraft to appear on DSN Now, such as Cassini. These are names the engineers apply to the test they’re conducting so data can be tracked through the subsystems that support DSN operations. These may trigger a flow of data suggesting the antenna is preparing to talk to a non-existent spacecraft such as DOUG or SHAN. When this occurs, engineers ask the antenna to ‘drop lock’ and the hunt for the spacecraft continues.Įngineers occasionally need to conduct system tests with an antenna or its subsystems. For example, attempts to recover the Opportunity Rover (MERB) may appear successful when the antenna has actually locked on to a signal from one of the orbiters around Mars such as MAVEN or MRO. This is particularly common with spacecraft at Mars as multiple spacecraft are within the field of view of a single DSN antenna. While the ground station is searching for a signal, it may ‘lock on’ to a signal from a different spacecraft and wrongly identify it as the spacecraft being searched for. In off-nominal scenarios when a project may be attempting to recover a spacecraft that is in safe mode or experiencing other operational challenges, an antenna may wrongly report that is receiving data from the spacecraft in question. If all the antenna of one or more of the three complexes are showing no activity it may be a ‘global downtime’ maintenance activity or a temporary glitch in the pipeline of data to DSN Now. It is not referencing a schedule of planned communication sessions. Data SourcesĭSN Now is driven by real-time data provided by the ground stations of the Deep Space Network and is updated every 5 seconds. Click a dish to learn more about the live connection between the spacecraft and the ground. Below is the current state of the Deep Space network as established from available data updated every 5 seconds.
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