Syuzo Isobe

Overview of JAXA Space Debris Surveillance Operations

S Sputnik 1 was launched on 4 October 1957, approximately 6000 satellites have been launched. With increasing launch and development of space activities, the space debris environment has also started to take shape. So far, nearly 30,000 objects including satellites, rocket bodies, and those fragmentations have been put into orbit. Twenty thousand have already decayed, whereas more than 7000 space debris objects are still drifting around the Earth. Depending on the solar activity, 150–500 space debris objects reenter the atmosphere each year. On the other hand, the number of reentering space debris objects are still limited, and referring to the database of U.S. Space Track [1], the total number of space debris objects has increased by roughly 800 in the past 10 years, even though this increase is becoming more gradual than it was in the 1970s or 1980s.

Wide field NEO survey 1.0-m telescope with 10 2k×4k mosaic CCD camera

We developed a new 1.0 m telescope with a 3 degree flat focal plane to which a mosaic CCD camera with 10 2k×4k chips is fixed. The system was set up in February 2002, and is now undergoing the final fine adjustments. Since the telescope has a focal length of 3 m, a field of 7.5 square degrees is covered in one image. In good seeing conditions, 1.5 arc seconds, at the site located in Bisei town, Okayama prefecture in Japan, we can expect to detect down to 20th magnitude stars with an exposure time of 60 seconds. Considering a read-out time, 46 seconds, of the CCD camera, one image is taken in every two minutes, and about 2,100 square degrees of field is expected to be covered in one clear night. This system is very effective for survey work, especially for Near-Earth-Asteroid detection.

Mosaic array cameras for NEO and space debris: an update

The recent interest in detecting asteroids and Reentrant Space Debris has developed a need for large field of view, high-resolution focal plane array cameras to provide for mapping and tracking of these objects. Ideally, a number of these cameras would be used around the world to provide a compete sky map. The Japan Space Forum is currently constructing one such facility in Japan. This paper is an update to the construction of tow cameras for the SJHF Bisei Spaceguard Facility. The camera for the 0.5 meter telescope has been installed and is operation. The camera for the 1.0 meter telescope is scheduled to be completed in June of 2001.

The position of the Japanese Spaceguard Association with regard to NEO problems

Abstract The Japanese Spaceguard Association, set up in October 1996, has been proposing a scenario to solve NEO problems. In addition to activities such as public lectures and publication of a newsletter, we are trying to get support from the government and private organizations to build ground-based, space-based and lunar-based telescopes. The construction of two ground-based telescopes began in January 1999, and will be operational in 2000. Proposals for lunar-based and space-based NEO missions are under discussion within NASDA, Japan. In this paper, we show the basis for the ideas at each stage although there is still continuing discussion within the JSGA.

Cost-effective advanced technology telescope system for detecting near-Earth objects and space debris

We are currently constructing a 0.5-meter and a 1-meter wide-field telescope that will operate in tandem to detect and track Near Earth Objects and space debris. The telescopes have a single flat-plane Cassegrain focus, are optimized for a specific range of wavelengths of light, a small focal ratio with a wide field of view, and hold a single multi-chip CCD camera as their only observational instrument. Because these telescopes are designed for a specific type of observation, the costs of the telescopes are greatly reduced compared to similar sized multipurpose telescopes systems. To achieve high-quality NEO/Space Debris observations, the manufacturers of the telescope systems, CCD cameras, facilities, and software work together to integrate their cutting-edge technologies into a single robust system. In this paper we discuss the strategy, design, and implementation of our manufacturing team approach to building cost-effective advanced technology telescope systems.

Mosaic array cameras for NEO and space debris

The recent interest in detecting asteroids and Reentrant Space Debris has developed a need for large field of view, high-resolution focal pane array cameras to provide for mapping and tracking of these object. Ideally, a number of these cameras would be used around the world to provide a complete sky map. The Japan Space Forum is currently constructing one such facility in Japan. This paper describes the construction and features of two cameras to be used at the Japanese facility. One camera will be used in conjunction with a half-meter telescope and the second camera will be used with a one meter telescope. Features of the camera included radiative cooling of the focal pane array to minimize stress on the detector assembly, a specially designed focal pane array mount to maintain flatness, a 24 hour hold time liquid nitrogen dewar, and high speed fiber optic readout. The cameras feature arrays of up to ten SITe ST002 2048 by 4096 backthinned CCDs for high performance and wide field of view.

Education and research opportunities for mining the data of the Bisei Spaceguard Center

The Bisei Spaceguard Center is an observatory complex located in Bisei Town Japan that comprises a 0.5-meter and a 1.0-meter very wide field automated telescope system. It is a joint project of the Japan Space Forum and the Japan Spaceguard Association. The mission of the Bisei Spaceguard Center is to detect Near Earth Objects (NEOs) and to do follow up observations to help determine the orbits of the newly detected and currently known NEOs.

Proposed lunar-based telescopes for NEO observations

Abstract The first lunar-based telescope for a test of NEO observations is discussed within a scenario of NASDAs sequence of lunar missions. There have been no real telescopes on the moon as yet, and therefore we have to step up from a primitive level of telescope to real NEO telescopes. The first telescope with an aperture of 30 cm is expected to be launched around 2005.