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1. UNDERSTANDING THE IMPACT OF SATELLITES ON RADIO ASTRONOMY OBSERVATIONS

   Peel, M; Eggl, S; Rawls, ML; Qui, H; Clements, DL (May 2025, European Space Agency Space Debris Office)

   Lemmens, S; Flohrer, T; Schmitz, F (Ed.)

   Radio telescopes observe extremely faint emission from astronomical objects, ranging from compact sources to large scale structures that can be seen across the whole sky. Satellites actively transmit at radio frequencies (particularly at 10±20 GHz, but usage of increasing broader frequency ranges are already planned for the future by satellite operators), and can appear as bright as the Sun in radio astronomy observations. Remote locations have historically enabled telescopes to avoid most interference, however this is no longer the case with dramatically increasing numbers of satellites that transmit everywhere on Earth. Even more remote locations such as the far side of the Moon may provide new radio astronomy observation opportunities, but only if they are protected from satellite transmissions. Improving our understanding of satellite transmissions on radio telescopes across the whole spectrum and beyond is urgently needed to overcome this new observational challenge, as part of ensuring the future access to dark and quiet skies. In this contribution we summarise the current status of observations of active satellites at radio frequencies, the implications for future astronomical observations, and the longer-term consequences of an increasing number of active satellites. This will include frequencies where satellites actively transmit, where they unintentionally also transmit, and considerations about thermal emission and other unintended emissions. This work is ongoing through the IAU CPS. 

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2. A Newly Documented Whole‑Sky Circumpolar Constellation in Alaskan Gwich’in

   Cannon, Chris; Holton, Gary (January 2014, Arctic anthropology)

   Traditional approaches to the documentation of indigenous astronomical knowledge often assume a one-to-one or near one-to-one correspondence between indigenous and classical constellation terms. Only a single constellation, equated with the Big Dipper, is robustly attested across the Northern Dene languages. Here we provide evidence from Gwich’in (Dene) that shows that the equation of this single Gwich’in constellation with the classical constellation is only partial. The Gwich’in constellation yahdii is actually a whole-sky constellation that maps nearly the entire sky. The Big Dipper is the tail of yahdii, and the remaining stars in the constellation are identified by other Gwich’in body-part terms, forming a unified functional conceptualization of the sky. Our work demonstrates how observational and cultural biases can prejudice the description of cultural astronomy. Dene astronomy is much richer than has been previously claimed and provides the first well-documented indigenous example of a whole-sky constellation. 

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3. Toward Spectrum Coexistence: First Demonstration of the Effectiveness of Boresight Avoidance between the NRAO Green Bank Telescope and Starlink Satellites

   https://doi.org/10.3847/2041-8213/ad6b24  

   Nhan, Bang D; De_Pree, Christopher G; Iverson, Matt; Gregory, Brenne; Dueri, Daniel; Beasley, Anthony; Schepis, Brian (August 2024, The Astrophysical Journal Letters)

   Abstract NRAO and SpaceX have been engaged in coordinated testing efforts since Fall 2021, including conducting experiments on different interference avoidance schemes for the Karl G. Jansky Very Large Array in New Mexico, and the Green Bank Telescope (GBT) inside the National Radio Quiet Zone in West Virginia. The Starlink system is capable of avoiding direct illumination of telescope sites with their adaptive tasking to place downlink beams far away. Nevertheless, even satellites operating in this mode can potentially present strong signals into the telescope’s receiver system if they pass close to the telescope’s main beam at the boresight. For additional protection, Starlink satellites can either momentarily redirect or completely disable their downlink channels while they pass within some minimum angular separation threshold from the telescope’s boresight, methods that are referred to as “telescope boresight avoidance.” In two separate experiments conducted since Fall 2023, NRAO and SpaceX arranged to have the GBT observe a fixed R.A./decl. position in the sky, chosen to have a large number of close-to-boresight Starlink passages. Preliminary analysis from these two experiments illustrates the feasibility of these avoidance methods to significantly reduce, if not eliminate, the negative impact of close-to-boresight satellite passages. Importantly, these experiments demonstrate the value of continuing cooperative efforts between NRAO and SpaceX, and expanding cooperation between the radio astronomy and satellite communities more generally. 

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4. Optimization of the Observing Cadence for the Rubin Observatory Legacy Survey of Space and Time: A Pioneering Process of Community-focused Experimental Design

   https://doi.org/10.3847/1538-4365/ac3e72  

   Bianco, Federica B.; Ivezić, Željko; Jones, R. Lynne; Graham, Melissa L.; Marshall, Phil; Saha, Abhijit; Strauss, Michael A.; Yoachim, Peter; Ribeiro, Tiago; Anguita, Timo; et al (December 2021, The Astrophysical Journal Supplement Series)

   Abstract Vera C. Rubin Observatory is a ground-based astronomical facility under construction, a joint project of the National Science Foundation and the U.S. Department of Energy, designed to conduct a multipurpose 10 yr optical survey of the Southern Hemisphere sky: the Legacy Survey of Space and Time. Significant flexibility in survey strategy remains within the constraints imposed by the core science goals of probing dark energy and dark matter, cataloging the solar system, exploring the transient optical sky, and mapping the Milky Way. The survey’s massive data throughput will be transformational for many other astrophysics domains and Rubin’s data access policy sets the stage for a huge community of potential users. To ensure that the survey science potential is maximized while serving as broad a community as possible, Rubin Observatory has involved the scientific community at large in the process of setting and refining the details of the observing strategy. The motivation, history, and decision-making process of this strategy optimization are detailed in this paper, giving context to the science-driven proposals and recommendations for the survey strategy included in this Focus Issue. 

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5. Share and Share Alike? An Exploration of Secure Behaviors in Romantic Relationships

   Park, Cheul Young; Faklaris, Cori; Zhao, Siyan; Sciuto, Alex; Dabbish, Laura; Hong, Jason (August 2018, Fourteenth Symposium on Usable Privacy and Security ({SOUPS} 2018))

   Security design choices often fail to take into account users' social context. Our work is among the first to examine security behavior in romantic relationships. We surveyed 195 people on Amazon Mechanical Turk about their relationship status and account sharing behavior for a cross-section of popular websites and apps (e.g., Netflix, Amazon Prime). We examine differences in account sharing behavior at different stages in a relationship and for people in different age groups and income levels. We also present a taxonomy of sharing motivations and behaviors based on the iterative coding of open-ended responses. Based on this taxonomy, we present design recommendations to support end users in three relationship stages: when they start sharing access with romantic partners; when they are maintaining that sharing; and when they decide to stop. Our findings contribute to the field of usable privacy and security by enhancing our understanding of security and privacy behaviors and needs in intimate social relationships. 

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