Update for 10:05 p.m. ET on Dec. 16: The planned Dec. 16 launch of the Michibiki 5 navigation satellite was scrubbed with less than a minute left in the countdown. A new target date has not yet been announced.
Japan will launch a new navigation satellite to orbit tonight (Dec. 16), and you can watch the action live.
An H3 rocket is scheduled to launch the Michibiki 5 spacecraft from Tanegashima Space Center today at 9:10 p.m. EST (0210 GMT and 11:10 a.m. local Japan time on Dec. 17).
You can watch it here at Space.com, courtesy of the Japan Aerospace Exploration Agency (JAXA), or directly via the agency. Coverage will begin at 8:15 p.m. EST (0115 GMT).
The 10,580-pound (4,800-kilogram) Michibiki 5 will be part of the Quasi-Zenith Satellite System (QZSS), Japan's homegrown navigation network in geosynchronous orbit.
"This system is compatible with GPS satellites and can be utilized with them in an integrated fashion," Japanese officials wrote in a description of the QZSS project.
"QZSW can be used even in the Asia-Oceania regions with longitudes close to Japan, so its usage will be expanded to other countries in these regions as well," they added.
Five QZSS satellites have reached orbit to date, starting with a pathfinder that launched in September 2010. That spacecraft, called Michibiki 1, was replaced by Michibiki 1R, which flew in October 2021.
Michibiki 5 will make QZSS a five-satellite system. But the launches won't end there: The constellation will eventually consist of 11 spacecraft, if all goes to plan.
Tonight's launch will be the seventh to date for the two-stage H3, the successor to Japan's workhorse H-2A, which retired this past June after 24 years of service.
The H3 failed during its debut launch in March 2023, resulting in the loss of the ALOS-3 Earth-observing satellite. But the medium-lift rocket bounced back strong, acing its next five missions, including a February 2025 launch that sent another Michibiki satellite to orbit.
Editor's note: This story was updated at 10:05 p.m. ET on Dec. 16 with news of the launch scrub.
