posted 11-10-2009 05:00 AM               

We will deliver your message to the bright star Venus

The Venus Climate Orbiter "AKATSUKI" (PLANET-C) is the world's first planetary meteorological observation satellite to unveil the mysteries of wind on Venus. It will explore the mechanism of the Venus climate by observing the atmospheric movement and cloud formation process. Ultimately, this mission aims to deepen our understanding of the formation process of the Earth's environment and its future by comparing Venus and the Earth.

JAXA would like to enhance people's interest in space and the Earth by holding a "message campaign" in which we invite people to send us messages that will be printed in fine letters on an aluminum plate and placed aboard the Venus Climate Orbiter "AKATSUKI".

Above: Location of plates and Aluminum plate image. (JAXA)

We will accept messages both from Japan and overseas so that we can bind the feelings and thoughts of everybody in the world into one, and inject it into the orbit of Venus. Through this campaign, we would like to boost the public's knowledge about Japanese space science research activities in Japan as well as abroad.

With the cooperation of the "International Year of Astronomy 2009 Japan Committee," we would like to carry out the "message campaign" to collect messages to be attached to the Venus Climate Orbiter "AKATSUKI.

posted 11-10-2009 07:31 AM               

Venus Climate Orbiter "PLANET-C" Nicknamed "AKATSUKI"

The Japan Aerospace Exploration Agency (JAXA) is scheduled to launch the Venus Climate Orbiter "PLANET-C" in Japan Fiscal Year 2010.

JAXA has decided the nickname of the PLANET-C as follows.

1. Name: Venus Climate Orbiter "AKATSUKI" (meaning "Dawn")

2. Reasons for naming:
   • The name was discussed and decided by the PLANET-C project team.

   • "AKATSUKI" means "dawn" when Venus shines most brightly as the first graying of dawn appears in the east sky just prior to sunrise.

     The AKATSUKI is scheduled to arrive at Venus, which beautifully shines as the "morning bright star" at dawn, in the winter of 2010. The name also reflects the purpose of the PLANET-C project to newly create planetary meteorology by exploring Venus. The word "AKATSUKI", which indicates the start of a day, implies not only a beautiful scenic image, but also the power of achieving a goal, thus the name carries the thoughts and determination toward the success of the mission.

   • By publishing the nickname well in advance of its launch, we intend to make people more familiar with the satellite and its launch preparations, actual launch, and on-orbit operations.

Venus is a similar planet to earth and rotates around the Sun, but Venus's rotation orbit is a bit closer to the Sun than that of the Earth. Venus is believed to have been formed in a similar process to the Earth's formation about 4.6 billion years ago, hence the two planets are thought to be like twins. However, the environment on Venus is quite different from that of Earth. There are no oceans there, and its atmosphere consists of heavy carbon dioxide that causes the greenhouse effect to make Venus a tropical heat world of 460 degrees Celsius. Up above Venus, clouds of sulfuric acid are swiftly flowing at a speed of 400 km per hour.

The Venus Climate Orbiter "AKATSUKI" (PLANET-C) is the world's first planetary meteorological observation satellite to unveil the mysteries of wind on Venus. It will explore the mechanism of the Venus climate by observing the atmospheric movement and cloud formation process. Ultimately, this mission aims to deepen our understanding of the formation process of the Earth's environment and its future by comparing Venus and the Earth.

posted 05-17-2010 04:18 PM               

H-IIA F17 with Akatsuki and Ikaros onboard moved to Pad 1

The H-IIA Launch Vehicle No. 17 with the Venus Climate Orbiter "AKATSUKI" and the Small Solar Power Sail Demonstrator "IKAROS" onboard left the Vehicle Assembly Building at 6:01 a.m. on the morning of the 17th (JST, 4:01 p.m. CDT Sunday) and arrived at the Launch Pad 1 at 6:25 a.m. JST.

We will load propellant to be ready for the launch at 6:44:14 a.m. on the 18th (Tue., JST, 4:44:14 p.m. CDT Monday).

posted 05-17-2010 04:53 PM               

Launch Postponement of Venus Climate Orbiter 'AKATSUKI'

Mitsubishi Heavy Industries and the Japan Aerospace Exploration Agency would like to announce that we have decided to postpone the launch of the Venus Climate Orbiter "AKATSUKI" by H-IIA Launch Vehicle No. 17 as we observed clouds including a freezing layer that exceeded the restrictions for suitable weather.

The launch was originally scheduled for May 18, 2010 (JST) from the Tanegashima Space Center.

We will inform the new launch date as soon as it is determined.

posted 05-18-2010 09:34 AM               

New Launch Day of Venus Climate Orbiter 'AKATSUKI'

After studying weather conditions from tomorrow, we decided to carry out the launch at 6:58:22 a.m. JST on May 21, 2010 (4:58:22 p.m. CDT May 20) because the weather is expected to recover in that time frame.

posted 05-20-2010 07:18 PM               

Launch Result of the Venus Climate Orbiter Akatsuki (Planet-C) aboard H-IIA Launch Vehicle No. 17

Mitsubishi Heavy Industries and the Japan Aerospace Exploration Agency launched the Venus Climate Orbiter Akatsuki (Planet-C) aboard H-IIA Launch Vehicle No. 17 (H-IIA F17) at 6:58:22 a.m. on May 21, 2010 (Japan Standard Time, JST) from the Tanegashima Space Center.

The launch vehicle flew smoothly, and, at about 27 minutes and 29 seconds after liftoff, the separation of the Akatsuki was confirmed.

posted 07-07-2010 09:40 AM               

Orbit Control Maneuver Result of the Venus Climate Orbiter 'Akatsuki'

The Venus Climate Orbiter "Akatsuki," which was launched on May 21, 2010 (Japan Standard Time), turned on the orbital maneuvering engine (OME) to jet 500 Newton (N) of thruster on June 28 (JST) at a distance of 14.6 million km from the earth or 1.06 astronomical units (AU) from the sun.

As a result, we have successfully performed on-orbit verification of the ceramic thruster, made of silicon nitride (Si3N4) for the first time in the world. The thruster was newly developed in Japan.

This thruster is a liquid rocket engine using hydrazine and nitrogen peroxide, and it is mainly used for retrofiring when the orbiter is injected into the Venus orbit.

The thrust emitted this time is not only for adjusting the access to Venus, but is also an imperative operation to evaluate the thrust characteristics of the engine for Venus orbit insertion. As a result of our detailed orbit tracking by the JAXA Uchinoura Space Center, JAXA Usuda Deep Space Center, and NASA Deep Space Network (DSN) stations, we have confirmed that about 12 meters per second of velocity correction was performed by 13-second firing of the OME, and that met the range of the scheduled orbit control.

The next orbit control (fine adjustment) is scheduled in early November, and Akatsuki will go to the nearest point of Venus and be injected into the Venus orbit on December 7 (JST).

Currently, the explorer and its onboard devices are working properly, and the Ultra-Stable Oscillator (USO) was also found to be functioning well to achieve the frequency stability as expected in addition to the Ultraviolet Imager (UVI,) 1µm Camera (IR1) and Longwave IR Camera (LIR,) whose initial functional verifications were already completed on the launch day evening.

posted 12-07-2010 10:57 PM               

Venus Climate Orbiter 'Akatsuki' Venus Observation Orbit Injection (VOI-1) Result

The Institute of Space and Astronautical Science of the Japan Aerospace Exploration Agency (ISAS/JAXA) performed Venus orbit insertion maneuver (VOI-1) for the Venus Climate Orbiter "Akatsuki" at 8:49 a.m. on December 7 (Japan Standard Time) but unfortunately, we have found that the orbiter was not injected into the planned orbit as a result of orbit estimation.

The "Akatsuki" was launched from the Tanegashima Space Center on May 21, 2010 (JST).

JAXA has set up an investigation team led by ISAS Director within JAXA to study the cause of the failure. We will update you with the countermeasures and investigation results.

posted 12-08-2010 04:38 AM               

Akatsuki Venus orbit injection plan to be reviewed

JAXA found that we have failed to inject the Venus Climate Orbiter "Akatsuki" into the planned Venus orbit after conducting the Venus orbit insertion maneuver (VOI-1) on December 7.

While we set up a new investigation team to study the cause and countermeasures, we will also review the Venus orbit injection plan again to take the next opportunity in six years when the Akatsuki flies closest to Venus.

posted 12-05-2015 07:54 PM               

Akatsuki: Second attempt to enter Venus orbit

The Venus Climate Orbiter Akatsuki will try to enter the orbit of Venus on Dec. 7 (Monday) after five years of operation. We are welcoming support messages.

After Akatsuki's failure to enter Venus' orbit on Dec. 7, 2010, JAXA investigated the cause and considered a second attempt schedule while operating the satellite for a long period. Now, on Dec. 7, 2015, coincidentally the same day on the calendar as the previous attempt, we will perform the injection for the second time.

The Akatsuki is in a good condition and it will take a few days of confirmation to know the result. Your support for the Akatsuki and its project team members is very much appreciated.

posted 12-06-2015 09:11 PM               

Akatsuki attitude control engine thrust operation performed as scheduled

JAXA performed the attitude control engine thrust operation of the Venus Climate Orbiter "Akatsuki" for its Venus orbit insertion from 8:51 a.m. on December 7 (Japan Standard Time).

As a result of analyzing data transmitted from the orbiter, we confirmed that the thrust emission of the attitude control engine was conducted for about 20 minutes as scheduled!

The orbiter is now in good health. We are currently measuring and calculating its orbit after the operation. It will take a few days to estimate the orbit, thus we will announce the operation result once it is determined.

posted 12-09-2015 06:36 AM               

Venus Climate Orbiter "Akatsuki" Inserted Into Venus' Orbit

The Japan Aerospace Exploration Agency (JAXA) successfully inserted the Venus Climate Orbiter "Akatsuki" into the orbit circling around Venus.

As a result of measuring and calculating the Akatsuki's orbit after its thrust ejection, the orbiter is now flying on the elliptical orbit at the apoapsis altitude of about 400 km and periapsis altitude of about 440,000 km from Venus. The orbit period is 13 days and 14 hours. We also found that the orbiter is flying in the same direction as that of Venus's rotation.

The Akatsuki is in good health.

We will deploy the three scientific mission instruments namely the 2μm camera (IR2), the Lightning and Airglow Camera (LAC) and the Ultra-Stable oscillator (USO) and check their functions. JAXA will then perform initial observations with the above three instruments along with the three other instruments whose function has already been confirmed, the Ultraviolet Imager (UVI), the Longwave IR camera (LIR), and the 1μm camera (IR1) for about three months. At the same time, JAXA will also gradually adjust the orbit for shifting its elliptical orbit to the period of about nine days. The regular operation is scheduled to start in April, 2016.

posted 12-10-2015 08:15 AM               

Akatsuki successfully inserted into Venus' orbit

As a result of measuring and calculating the Akatsuki's orbit after its thrust ejection on Dec. 7, JAXA found that the Akatsuki was inserted into the Venus orbit.

We have already received images from three instruments whose function has already been confirmed, namely the Ultraviolet Imager (UVI), the Longwave IR camera (LIR), and the 1μm camera (IR1).

We will check the function of the three other scientific mission instruments and perform initial observation for about three months while gradually adjusting the orbit for shifting its elliptical orbit to the period of about nine days. The regular operation is scheduled to start in April, 2016.

Above: Venus image taken by AKATSUKI immediately after its attitude control ejection. By 1μm camera (IR1) at around 1:50 p.m. on Dec. 7 (Japan Standard Time) at the Venus altitude of about 68,000 km.

Above: By Longwave IR camera (LIR) at around 2:19 p.m. on Dec. 7 (Japan Standard Time) at the Venus altitude of about 72,000 km.

Above: By Ultraviolet Imager (UVI), at around 2:19 p.m. on Dec. 7 (Japan Standard Time) at the Venus altitude of about 72,000 km.

posted 05-29-2024 07:48 AM               

Communication status with the Venus probe 'AKATSUKI'

The Japan Aerospace Exploration Agency (JAXA) launched the Venus probe "AKATSUKI" in 2010, and has been operating it for about 14 years since it was put into orbit around Venus in 2015, achieving high scientific results. After completing its regular operations following the project completion review in 2018, "AKATSUKI" was conducting observations as part of its later phase of operations. However, during operations at the end of April 2024, it was unable to establish communication due to a long period of control mode with low attitude maintenance accuracy.

Since then, various measures have been taken to restore communication, but communication has not yet been restored. We are currently working to restore communication.

The probe has already exceeded its design life of four and a half years since launch, and is now in the later phase of operations, so we are considering future responses. We will notify you as soon as JAXA's policy is decided.