###### Abstract
Split Light Studio developed an educational Solar System VR App ([[http://splitlightstudio.com/pages/movies_solar_system.html](http://splitlightstudio.com/pages/movies_solar_system.html)]([http://splitlightstudio.com/pages/movies_solar_system.html](http://splitlightstudio.com/pages/movies_solar_system.html)), accessed on 1 September 2021) that involves a tour of the planets and the Moon. Although it can help users understand the planets with colorful graphics, the contents are produced manually and cannot reflect the ever-changing appearances of celestial bodies. On 11 January 2010, the U.S. National Aeronautics and Space Administration (NASA) launched the Solar Dynamics Observatory (SDO) ([[https://www.nasa.gov/pdf/418329](https://www.nasa.gov/pdf/418329)]([https://www.nasa.gov/pdf/418329](https://www.nasa.gov/pdf/418329)) mainS_SSDOS_5 PressKit.pdf, accessed on 1 September 2021) that can continuously observe the Sun, as shown in Figure 1. This allows anyone, and not just experts, to observe the changes in the Sun. In this study, an IVR-based distance education system was proposed to enable multiple remote users to share and experience SDO images in real time via streaming. The requirements for building the IVR-SDO distance education system are as follows:  
**R1**: _Low-barrier of entry for people who are interested in SDO_. The system must be easy to use, even for non-experts. Only limited experts, such as space scientists or aeronautical meteorologists, have shown interest in existing SDO data. Although not well-known to the public, the SDO data provided on the web can be easily accessed by ordinary people. However, expert knowledge is still required to handle the data. Hence, it is necessary to lower the barrier to entry for the general public by providing a more accessible education method. Low-priced HMDs can replace expensive large-screen displays, and the limitations of place can be overcome by eliminating the need for remote visits using a network. **R2**: _Streaming immersive data visualization platform_. The system should provide users with immersive data visualization of SDO images via streaming through an HMD-based visualization platform. Streaming is required because it is practically difficult to archive large SDO images at a local site. An HMD is used because in desktop VR and CAVE, the user recognizes the screen, thus lowering immersion. A virtual space can immerse users by freely adjusting the size of the Sun image and arranging it in various ways. **R3**: _Realistic avatar-based embodied interactions_. To improve the social presence of participants, a realistic avatar model should be provided and controlled based on motions synchronized with the user. Furthermore, free communication using verbal interactions is possible. **R4**: _Physically distributed multiuser support for group learning._ It should enable group learning in which many physically distant users can participate together without being physically present. This is achieved by making them feel as if they are receiving education in the same space. The remainder of this paper is organized as follows. Section 2 introduces related work. Section 3 details the IVR-SDO distance education system. Specifically, the proposed system structure, network structure, and multichannel-based data transfer method for SDO image streaming are described. Section 4 presents the quantitative experiment results for the network utilization of the proposed IVR-SDO distance education system and the qualitative preference analysis results from user experiments. Finally, Section 5 provides the conclusions and directions for future research.