The Autonomous System Architecture of the Small SAR Satellite Operation System and On-Orbit Autonomous Operation Experiences

We are developing a small SAR (Synthetic Aperture Radar) satellite for our commercial solution business. Our goal is to deploy at least 30 small SAR satellites in orbit and enable frequent and persistent observations until the Mid 2020s. We launched the satellite on 15th December 2020 by Rocket Lab\u27s Electron. We waited for a month until we took the first image to confirm the complete evacuation of the residual air and contaminations to prevent any hazardous electrical discharge. We took the first image on 8th February. The satellite is now operating in a fine state and acquiring images requested by the customers. We will make six satellite constellation until 2023. We also describe our system architecture including our solution business and the satellite development. Our business development team and the satellite development team are communicating with each other for adequate system architecture and agile satellite development. Our business development team acquires many novel needs from our customers. One of our goals is an agile reflection of the user\u27s needs for the satellite development. We are now establishing a process and an organization to extract those business needs, analyze them and identify the key requirements for the satellite performances and functions. We believe that one important challenge is to achieve application layer integration from a customer business system to a satellite on-board software through solution platform, data platform, satellite control ground system, and the satellite itself. We try to harmonize the software and information processes of the application layer, although the platform where the application is located, the organization where staffs belong, and their culture are different. We wish our activities contribute to our small satellite community or ecosystem and a system architecture including component suppliers, communication service providers, and data processing service providers

Launching Small Satellites on the H-IIA Rocket

Over the last 40 years, the lowest cost transportation to space for small payloads has been achieved by utilizing excess capacity on large launches. Because the mass and volume used by small payloads on large vehicles are otherwise unused, often the pricing only needs to cover manifesting, integration and qualification of the so-called piggyback payload. Unfortunately this lack of economic incentive has suppressed supply – large rocket developers and operators may have little or no incentive to invest in small payload accommodations. In taking on the management of Japan\u27s newest and largest rocket, the H-IIA, from the National Space Development Agency of Japan (NASDA), Mitsubishi Heavy Industries has decided to aggressively pursue opportunities for comanifesting nano, micro and mini-satellites, leveraging proven capabilities developed by NASDA for small satellite launches on Japan\u27s largest launch vehicle. This new capability, to be demonstrated on the next H-IIA launch this year, has the potential to more than double the secondary space available to small payloads worldwide, and will reduce queuing time for launching small satellites

Structure of an antagonist-bound ghrelin receptor reveals possible ghrelin recognition mode

Ghrelin is a gastric peptide hormone with important physiological functions, including growth hormone release and appetite-stimulating activity. Here, authors solved the crystal structure of the ghrelin receptor bound to antagonist and suggested a possible mechanism of activation by acyl-modified ghrelin