Compared to the exuberance at similar NASA mission events, it feels quite subdued! The Akatsuki team achieved something that no mission has done before – put a spacecraft into orbit around a planet using only the attitude control thrusters. An event that one could not even conceive or propose!

Takeshi Imamura comes out of the control room into the work/break room and looks greatly relieved. He still has work to do. In fact now that the spacecraft is in orbit, the attitude of the spacecraft has to be continuously updated. The commands will be generated manually and uploaded until the orbit is known better.

For the insertion burn, the high-gain antenna could not be used because the orientation of the spacecraft required to be such as to produce thrust counter to the direction of motion to reduce the speed. The medium-gain antenna was receiving signal from the ground station and transponding it back to provide the two-way Doppler, since the entire maneuver was visible from Earth. However, the signal received from the medium-gain antenna is quite weak. When the telemetry data from Akatsuki started to be received after the 8 minute 20 second one-way light time delay, a graph was flashed on the right screen showing the expected cumulative velocity change for maximum thrust from the four rockets and several other curves showing values for different fractions of the maximum thrust. We are all watching the data trickle in – the real delta-V points were falling on the maximum thrust curve! Exciting!! Trajectory calculations were done elsewhere using the data from Usuda (JAXA) and Canberra (NASA/JPL DSN). At one moment there is a break in the graph, a gasp is heard, but the graph resumes again as the data flow continues. The Usuda DSN had switched to a different orbit model, which caused a few seconds break.

12:00 PM JST Press Briefing

JAXA's press release on the successful arrival at Venus is posted on their website.

The conference hall at ISAS is full of media persons. Nakamura arrives and an ISAS Press Officer asks him some questions, a after a few words begins taking questions from the media. No handlers for the briefing, no senior officials from ISAS or JAXA – is the Program Manager’s show. I notice only a few persons from the Akatsuki team. Very different from a typical NASA briefing.

Masato is smiling answering questions – it is all in Japanese, so I cannot understand anything, except guess at the question and the answer from Nakamura when he uses the spacecraft model to illustrate. At one point there was laughter - Prof. Nakamura said that unfortunately he cannot give a refund for the express ticket to Venus, but glad that he took us to Venus.

In half an hour the briefing is over.