# Advances in Remote Sensing and Propulsion Systems for Earth Observation Nanosatellites
## 1 Introduction
The article discussed the increasing number of applications for nanosatellites and planned EO missions across various scientific fields, which universities, space agencies, and private sector organizations are pursuing. Private sector companies are primarily leading the development of new missions, proposing projects that range from smaller constellations to more ambitious ones involving over a thousand nanosatellites. The authors highlight ongoing efforts to improve image quality, increase data acquisition frequency by utilizing more significant constellations, and cater to specific applications such as monitoring natural disasters. The \begin{table}
\begin{tabular}{c c} \hline \hline
**Study** & **Key Insights** \\ \hline [PERSON] and [PERSON] [6] & Overview of small satellite evolution, highlighting the shift toward smaller, dedicated satellites. \\ \hline [PERSON] et al. [7] & Affordability and growing applications of nanosatellites for EO, with a focus on enhancing image quality. \\ \hline [PERSON] and [PERSON] [8] & Global survey on nanosatellite projects, highlighting the impact of CubeSat standard and subsystem technologies trends. \\ \hline [PERSON] [9] & Review of small satellite formation flying missions, with a focus on constellation design and Earth science missions. \\ \hline [PERSON] et al. [10] & Exploration of CubeSat mission goals, subsystems, and future challenges in deploying CubeSat networks. \\ \hline [PERSON] and [PERSON] [11] & Assessment of CubeSats advantages, including lower costs and the concept of large constellations for EO missions. \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Surveys on nanosatellites. survey focuses on the most successful private constellation, PlanetScope (PS) and Doves. It includes a systematic review of published articles that shed light on the most recent innovations and advancements in nanosatellite technology. [PERSON] and [PERSON] [8] present the findings of a comprehensive global survey on publicly known pico- and nanosatellite projects. They emphasize the significant impact of the CubeSat standard on the proliferation of nanosatellites, particularly toward the end of the twentieth century, resulting in approximately a hundred projects worldwide by August 2009. Compared to larger satellites, pico- and nanosatellites are distinguished by their shorter development time, cost-effectiveness, and utilization of cutting-edge technologies. The survey aims to enhance understanding of the current technological landscape and applications of nanosatellites and identify trends in the global development of such projects. Noteworthy discoveries include the overall advanced nature of most subsystem technologies, except attitude control systems and related performance characteristics. The authors highlight that education and technology demonstration remain the predominant mission objectives, although some projects have also ventured into scientific experiments. [PERSON] [9] conducted a comprehensive review of thirty-nine small satellite missions, mainly focusing on popular nanosatellite platforms like CubeSats. The primary emphasis is on formation flying missions, leveraging small satellites' modular nature and cost-effectiveness. The surveyed missions are analyzed and categorized based on several criteria, including mission type, mission status, number of satellites, leading organization, funding source, and the necessity for constellation or formation flying. The study reveals that Earth science-related missions are the most prevalent among the surveyed projects, and most multi-satellite missions only require a constellation. Notably, six missions aim to demonstrate formation-flying capabilities using two to three small satellites, while only two formation-flying missions plan to utilize four or more small satellites. This survey provides valuable insights into the landscape of small satellite missions, shedding light on their diversity, applications, and the evolving trend toward formation flying. [PERSON] et al.