Venus Climate Orbiter “AKATSUKI” Press Kit

Venus Climate Orbiter “AKATSUKI”

Japan Aerospace Exploration Agency PLANET-C Project1

Venus Climate Orbiter “AKATSUKI” Press Kit

Overview of the AKATSUKI
 Japan’s first Venus explorer
 Scientific purpose
To understand the evolution of the climate ofVenus, Earth’s sister planet, by studying theoverall movement of the Venus atmosphere.
 Launch in May 2010
Arrive at Venus in Dec. 2010

Venus
Venus has been well known as the “morningbright star” and “evening bright star” sinceancient times, and its size and mass are mostsimilar to the Earth.
However, its environment is quite different
from that of the Earth. Venus is covered by athick carbon dioxide atmosphere and sulfuric
acid clouds with extremely strong winds of
100 meters per second called “super rotation.”- Why does super rotation occur?
- How does the meridian-planecirculation work?
- How are clouds formulated?
- Do lightening and thunder occur?
- Are there active volcanoes?

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Venus Climate Orbiter “AKATSUKI” Press Kit

Characteristics of AKATSUKI
Major characteristics

Shape/Size

Scheduled orbit

Design life

Box shape with two wing-typesolar array paddles(1.04 m x 1.45 m x 1.40 m)
Venus elliptical orbit
Peri-Venus altitude: 300 km
Apo-Venus altitude: about 80,000
kmOrbit period: 30 hours
Orbit inclination angle: 172
degrees
About two Earth years after
arriving at Venus

Mass

About 500 kg at the time of liftoff

Generated Power

About 500 w in the Venus orbit (atthe end of the mission)New
technologies
adopted toAKATSUKI
Regenerative ranging
transponder

Lithium-ion battery

High-gain flat-type RLSA
antenna

Ceramic thruster

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Venus Climate Orbiter “AKATSUKI” Press Kit

AKATSUKI Onboard Observation Devices
 AKATSUKI is equipped with six
observation devices--

Five observation cameras that can capture
various wave lengths ranging fromultraviolet to long-wave infrared (IR1, IR2,LIR, UVI, and LAC)
Basic signal source for radio occultation
measurement (USO) Four cameras and their data except LAC
are controlled, processed and recorded by
the Sensor Digital Electronics Unit (DE, a
comprehensive mission systemcomputer.) Compared to the satellite mass of about
500 kg, the total mass of six observation
devices and DE is only about 37 kg.

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1μm Camera (IR1)
PI: Naomoto Iwagami (University of Tokyo)
With wavelength of around 1 μm which enables it to penetrate through
Venus clouds to the ground, the IR1 will study cloud movement in thelower atmosphere, distribution of vapor, mineral composition on theground and existence of active volcanism.
1μm Camera (IR1)
Mass

About 6.7 kg*

View

12 degrees

Detector

Si-CSD/CCD(1024 pixel x 1024 pixel)
1.01 μm (Night: ground surface, clouds)Observation
wavelength(Observationtargets)

0.97 μm (Night: vapor)
0.90 μm (Night: ground surface, cloud)0.90 μm (Day: clouds)* Including the circuit part (about 3.9 kg) shared with IR25

Venus Climate Orbiter “AKATSUKI” Press Kit

2μm Camera (IR2)
PI: Takehiko Sato (ISAS/JAXA) With wavelength of around 2 μm which enables to see through Venus
clouds, the IR2 acquire basic data of circulation in the lower atmosphereand cloud physics based on its observations of cloud concentration, size ofcloud particles, and distribution of carbon monoxide.
 During its trip from the Earth to Venus, it also observes zodiacal light toclarify the behavior of interplanetary dust clouds.
2μm Camera (IR2)
MassAbout 18 kg*View

12 degrees

Detector

PtSi-CSD/CCD(1024 pixel x 1024 pixel)
1.735 μm (Night: clouds, particle size
distribution)

Observation
wavelength(Observationtargets)

2.26 μm (Night: clouds, particle size
distribution)
2.32 μm (Night: carbon monoxide)2.02 μm (Day: cloud top altitude)
1.65 μm (Zodiacal light* Including a freezer and thecircuit part (about 3.9 kg)
shared with IR26Venus Climate Orbiter “AKATSUKI” Press Kit

Long wave IR camera (LIR)
PI: Makoto Taguchi (Rikkyo University)
By translating cloud temperatures into images using infrared of 10 μm in
wavelength, the LIR clarifies wave motion and convection current motion
in stratus and wind speed distribution at a cloud top altitude on the nightside.
Long wave IR camera (LIR)
Mass

About 3.3 kg

View

12 degrees

Detector
Observation
wavelength(Observationtargets)

Uncooled bolometer(320 pixel x 240 pixel)
10 μm (Day/Night: cloud toptemperature)

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Venus Climate Orbiter “AKATSUKI” Press Kit

Ultraviolet Imager (UVI)
PI: Shigeto Watanabe (Hokkaido University)

By capturing ultraviolet radiation, the UVI observes sulfur dioxide which
relates to the formation of clouds and unidentified chemical substancesthat absorb ultraviolet wavelengths, then, through the changes of sulfur
dioxide and chemical substances, we will clarify wind speed distribution
at a cloud top altitude.
Ultraviolet Imager (UVI)
Mass

About 4.1 kgView

12 degrees

Detector
Observation
wavelength(Observationtargets)

Si-CCD(1024 pixel x 1024 pixel)
283 nm (Day: sulfur dioxide at cloudtop)
365 nm (Day: unidentified absorbent)

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Lightening and airglow camera (LAC)
PI: Yukihiro Takahashi (Hokkaido University)
The LAC observes faint light called airglow emitted from oxygen in theupper atmosphere at an altitude of about 100 km by visible spectrum totranslate changes of day and night circulation and atmospheric wave intoimages.

It will also clarify if lightening flashes of lightening discharge exists inVenus by high-speed exposure of 30,000 times per second (32 μsec
temporal resolution.)Lightening and airglow camera (LAC)
Mass

About 2.3 kg

View

16 degrees

Detector

8 x 8 APD matrix array
777.4 nm (Night: lightening flashes oflightening discharge)

Observation
wavelength(Observationtargets)

480-650 nm (Night: oxygen molecularairglow)
557.7 nm (Night: oxygen atom airglow)

545 nm (For calibration)

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Venus Climate Orbiter “AKATSUKI” Press Kit

Ultra-stable oscillator (USO)
PI: Takeshi Imamura (ISAS/JAXA)The USO is onboard for radio occultation measures. It will acquire
information on the thermal structure and perpendicular transmission waveof the Venus atmosphere by understanding altitude distribution oftemperatures based on changes in frequency and intensity of radio
waves emitted from PLANET-C to the ground through the Venus
atmosphere.
Ultra-stable oscillator (USO)
Mass

Observation
wavelength(Observationtargets)

About 2 kg
USO frequency 38 MHzTransmission frequency 8.4 GHz(Temperature, sulfuric vapor, electrondensity)

The USO is installed in theinside of the satellite.

Image of radio occultation measures

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Venus Climate Orbiter “AKATSUKI” Press Kit

AKATSUKI Scientific Goal
By remote sensing from the Venus orbit, the AKATSUKI aims at taking images of three-dimensional
movement inside the thick Atmospheric layer.

Research topics
To clarify the following: Comprehensive observation of wave
motions and turbulent currents, and theircontribution to the super rotation.
 Structure of the meridian-planecirculation
 Substance circulation in the cloud layer
and its role in maintaining the cloud layer Time and space distribution of lightening
discharge and its generation process
 Time and space distribution of airglow
and upper layer atmospheric circulation

Three-dimensional image of AKATSUKI observation

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Venus Climate Orbiter “AKATSUKI” Press Kit

AKATSUKI Observation Plan

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Venus Climate Orbiter “AKATSUKI” Press Kit

Pipeline for Image Data Processing
Data acquired by five onboard cameras will betransmitted to the ground, then it is processed
through the half-automated “pipeline process.”

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Venus Climate Orbiter “AKATSUKI” Press Kit

AKATSUKI Operation StationsCMD, TLM, RNG
Receiving only
VLBI ranging signals
onlyESAstationDomestic VLBIstation

Stations participating in anexperiment of deciding theVLBI orbit

USC34(Uchinoura)

UDSC64(Usuda)

Main and sub operational stations

DSN station: Goldstone, Canberra,
MadridSupport stations for launch / cruise /Venus orbit injection phases

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Venus Climate Orbiter “AKATSUKI” Press Kit

Launch Site Operation ScheduleDay
March 19March
30/31
April 2
April 27

April 30

May 4May 9May 18Operation
AKATUKI delivery

AKATSUKI to be transported to the Tanegashima
Space Center

Detailed electric test

Final electric verification to confirm onboard device
operation

Dress rehearsal

Confirm the launch operation including the groundsystems

Final visual inspection

Final visual inspection before launch

Mating with the payload attach fitting (PAF)
and payload support structure (PSS)AKATSUKI to be attached to the PAF, then to beloaded onto
the PSS, on which small secondary satellites areloaded.

AKATSUKI fairing encapsulation

AKATSUKI to be encapsulated in a fairing

AKATSUKI loading onto H-IIA

Encapsulated AKATSUKI to be loaded onto the H-IIA
Launch VehicleLaunch

Launch at 6:44:14 a.m. (Japan Standard Time)(Launch window: until June 3, launch time will be different day by day.)* The above schedule is subject to change due to operational progress.
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Venus Climate Orbiter “AKATSUKI” Press Kit

Trip to Venus
 Venus’s plane of revolution trajectory is tilted by 3
degrees.
Arrive at Venus

EarthVenus

Sun

 AKATSUKI launched from the Earth will fly to Venus
along the Earth’s plane of revolution trajectory.
 AKATSUKI can reach Venus with a small amount ofenergy because Venus is on the Earth’s revolution
trajectory plane when AKATSUKI comes closer toVenus.
[Image]Venus

Leave EarthVe
rev nusolu ’stiont

AKATSUKI
Ear th Launch in May 2010
→Arrive at Venus in Dec. 2010’s revoluti

ontr aje ct orSun
rajectoryÎyÎEarth16

Venus Climate Orbiter “AKATSUKI” Press Kit

Post Launch Operation Schedule
Operation schedule after launch






About 0.5 days after launch: First visible opportunity (check the satellite status)
About 1.5 days after launch: Second visible opportunity
try to take images of the EarthAbout 2.5 days after launch: Third visible opportunity
While traveling to Venus orbit: Observing zodiacal light by 2μm camera (IR”)
Early December: To be injected into the Venus orbit
January 2011: Regular operation starts

For more information about Venus Climate Orbiter “AKATSUKI”
 Special Site :http://www.jaxa.jp/countdown/f17/index_e.html
 AKATSUKI Project Site:
http://www.stp.isas.jaxa.jp/venus/top_english.html(Mission introduction, Scientific explanation of Venus, Project’s latest information)

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Venus Climate Orbiter “AKATSUKI” Press Kit

Development Organization – Domestic and International Cooperation
JAXA has been proceeding with this project through collaboration with domestic
universities and research institutes while maintaining strong promotional andcooperative ties with the Venus Express (Venus exploration) mission of theEuropean Space Agency.
InternationalUniversities
Hokkaido Univ. Tohoku Univ.
Univ. of Tokyo Rikkyo Univ.
Osaka Univ.

researchorganizations

Obser
deve vation delopm
vices
entInternational
cooperation

Communication equipment
development

Collaborative
observation

Tokyo Institute of Technology
Nagoya Univ. Kyoto Univ.
Tokyo Gakugei Univ.
Kobe Univ. Okayama Univ.
Univ. of Aizu Kyushu Univ.
Wakayama Univ.
Seoul National Univ.

Researchorganizations
Institute of Statistical
Mathematics
AIST
National Astronomical
Observatory of Japan

PLANET-C

NASA、ESA、
MPIVenus Express(ESA Venus explorer)

Observation data discussion

Projectmrisogaling ntse
esoc lopmrP veed
sse
deroc
fpoon
isiv
o
Pr tada(Note) MIP: Max-Planck Institute
IRF: Swedish Institute of Space Physics

Level 2 data (Verifiedscience data)

Planetary Meteorology
researchers in the world18

Venus Climate Orbiter “AKATSUKI” Press Kit

Nickname “AKATSUKI”
The nickname has been studied and decided among the project
team who has been involved in the development of the explorer.
It was announced on October 23, 2009, well before its launch, inorder for people to feel familiar with the explorer.
 “AKATSUKI” means dawn or daybreak, when Venus shines
most beautifully in the first graying of the east sky. The Venus
Climate Orbiter “AKATSUKU” will arrive at Venus, the morning
bright star in the dawn, in the winter of 2010.
 The name also matches with the image of newly creating a fieldof planetary meteorology through this exploration.
 The word “AKATSUKI” also implies not only the beautiful
daybreak scenery, but also power to achieve a goal, thus thename reflects the determination and eagerness for themission's success.

19Venus Climate Orbiter “AKATSUKI” Press Kit

Mission Logo
The mission logo mark of the "AKATSUKI" wasdesigned by reflecting its original nickname, "VCO,"
the abbreviation of the Venus Climate Orbiter, which
has been used since the initial study phase. In thelogo, the AKATSUKI is flying over Venus, which isshown by "O" in the drawing, on an orbit depicted by"C." It was designed by the AKATSUKI project team.

Two mascot characters were also introduced forpeople to feel more familiar with the AKATSUKI.

"AKATSUKI-KUN""KINSEI-CHAN"
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Venus Climate Orbiter “AKATSUKI” Press Kit“AKATSUKI” Message Campaign
 Campaign Overview“We will deliver your message to the brightest morning star Venus”
JAXA held the "AKATSUKI Message Campaign" in order to enhance people's understanding of the Venus Climate
Orbiter "AKATSUKI" and JAXA activities, to make people feel more interested in the exploration to the solar system,and to improve recognition of JAXA both in Japan and abroad.
In the campaign, we invited people to send us messages thatwould be placed aboard the AKATSUKI.
- Campaign Period
October 23 (Fri.) 2009 thru January 10 (Sun.) 2010
Î About 260,000 people sent messages.

Messages and names wereprinted on aluminum plates andloaded onto the AKATSUKI.
They will travel to Venus.

Aluminum plates printed withnames and messages

Loading position of Aluminum plates (Three locations)21