A Mitsubishi Heavy Industries H-IIA rocket placed the Michibiki 4 spacecraft into orbit yesterday. This is the latest element of Japan’s indigenous satellite navigation constellation. The Michibiki constellation, which means “guiding the way”, is also called QZS – quasi-zenith satellite – because the complementary orbits of the four spacecraft will ensure that there is always a satellite near the zenith (as long as you’re in the Eastern Hemisphere, anyway, and particularly near a band from Japan to Australia). They are all intended to operate at geosynchronous altitude, much higher than the GPS constellation, but at a significant inclination. Geostationary satellites orbit on the plane of the Earths’ equator, which allows them to appear fixed in the sky. Since these have an inclined orbit, they will trace a figure-8 pattern in the sky over the course of a day. This variation will give GPS receivers something to track. Yes, I did say GPS — Japan says this will be fully compatible with GPS signals. It will be particularly beneficial in the dense urban areas of Japan, where GPS struggles to be accurate due to all the buildings blocking satellite signals. With satellites that stand high in the sky all the time, it will be much easier to get enough signals for a fix.
This was H-IIA’s thirty-sixth launch.
Japan has launched their newest radar spy satellite, the Information Gathering Satellite (IGS) Radar 5, aboard the H-2A rocket from Tanegashima Space Center. It joins an existing constellation of spy satellites which Japan began assembling in 1998 following a North Korean missile launch that flew over Japanese territory. Officially, the IGS program supports civilian needs, such as disaster awareness, but the unspoken main goal is to keep tabs on Japan’s enemies. This launch of course was not in response to last week’s North Korean missile tests; satellites and launch vehicles take years to plan and procure. But I am sure Japan hopes for it to send a message all the same: we are watching.
Himawari 9, Japan’s latest weather satellite, has been launched into orbit by the H-2 rocket from scenic Tanegashima:
Himawari 9 will head up to geosynchronous orbit, where it will sit as an on-orbit spare for Himawari 8.
Meanwhile, Mitsubishi Heavy Industries, maker of the H-2 rocket, has announced their intention to offer the H-2 on the commercial launch market. It’s going to be interesting to see how things heat up over the next few years; it almost starts to seem as if we may have too many commercial providers. But if nothing else, it will create competition, and that’s usually good for business. It’s going to be a fun few years for space geeks!