JAXA’s Space Exploration Scenario for the Next

Twenty Years- Science Strategy -

Masato NakamuraSteering Committee of Space Science

Institute of Space and Astronautical ScienceJapan Aerospace Exploration Agency

ISASISAS NASDANASDA NALNAL

October 2003

ISASISAS

Japan Space Exploration Japan Space Exploration CenterCenter

JAXA

2007

ISAS’s mission from 1980s

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ISASISAS NASDANASDA NALNAL

October 2003

ISASISAS

Japan Space Exploration Japan Space Exploration CenterCenter

JAXA

2007

In 2006, the steering committee of space science of ISAS/JAXA started to renew its solar system exploration plan, which originally announced in late 1990’s and early 2000’s

Preparation committee of exploration center of JAXA also started to work on its original solar system exploration plan in 2006

Joint committee of above two worked on JAXA’s exploration plan and it is announced in May 2007.

JAXA’s approach to Solar System Science

4 Major Scientific Objectives for exploration of the solar system

Empirical explanation of the origin of the solar system

Explanation of the evolution and diversity of planets

Explanation of the environment required for life to occur and evolve

Understanding the origins of space plasma processes

Empirical explanation of the origin of the solar system

The objective here is to clarify how primordial solar nebula forms into planets. Towards that goal, Japan will explore primitive bodies in the solar system. These bodies contain a record of the initial stages in the formation of our solar system. From the exploration of Jovian planets and their satellites, it is possible to clarify the origin of gas planets and thereby impose restrictions on primordial solar nebula. Clarifying initial conditions and evolution of primordial solar nebula also plays an important role in the observation of protoplanetary disks and planetary systems outside our solar system. These observations rely heavily on cooperation with astronomical satellites, especially infrared astronomy satellites.

Explain the evolution and diversity of planets

Why is our Earth the only planet in the solar system with the appropriate conditions (e.g. atmosphere, oceans) to sustain life? What is the ultimate cause of planetary climate change? How are planetary magnetospheres generated and how do they become extinct? How does the mechanism that drives the crust and mantle differ among planets? The objective here is to clarify both our current environment and the 4.5 billion-year history since the birth of planets. To answer these fundamental questions, it is necessary to clarify 1) the structure, movement, and variation of planetary atmospheres; 2) the internal structure of planets; and 3) the topography and structure of planetary surfaces.

Explain the environment required for life

The search for life beyond Earth has the potential of expanding the study of Earth life science to the universal domain of space life science. This search will provide clues to the existence of intelligent life outside our solar system. The search for life beyond Earth includes many meaningful tasks such as exploring 1) the organic and volatile components of primitive bodies, 2) the conditions on Mars and the moons of outer planets (e.g. Europa, Titan), and 3) the planets outside our solar system that have the potential to support life.

Understanding the origins of space plasma processes

Through in situ space observations, the objectives here are to clarify space plasma phenomena and to deepen our unified understanding of planetary magnetospheres. This understanding will contribute greatly to the further clarification of 1) long-term changes in planetary environment under the influence of the sun, and 2) diverse cosmic plasma phenomena studied in solar physics and X-ray astronomy. Progress towards these objectives requires in situ observations of planetary magnetospheres other than the Earth and Sun along with super precise observations of the Earth’s magnetosphere and space plasma dynamics.

Four tasks to be challenged to approach these objectives

Lunar and terrestrial planetary science

Primitive bodies

Planetary atmosphere

Planetary magnetosphere and solar system plasma physics

Exploration roadmap of JAXA

On going mission (1)HayabusaLaunched in 2003

Arrival at Itokawa in 2005

Return to Earth in

2010

On going mission(2)

Mission in preparation(1)

Planet-C Venus Climate Orbiter

Launch May 2010Arrival Dec. 2010

Mission in preparation (2)

BepiColomboMercury Mission

Collaboration with ESA

Launch 2013

Terrestrial Planetary Exploration

Luna Interior exploration

Luna Landing and Sample return

Mars scientific exploration

SELENE 2

SELENE X

Mars mission

Primitive Body Exploration

Hayabusa-2C-type asteroid(Hayabusa like Spacecraft)

Hayabusa-Mk2（ Advanced Sample return mission）

Planetary Atmospheric Science

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Planetary meteorology

atmosphere evolution

climate change

Exploring planetary climate: from Venus to Mars

Understanding the evolution and diversity of planetary climate

PLANET-C / Venus Climate Orbiter (2010) Heritages of

technology

Venus balloon

Mars orbiter

Mars lander

...... 2026 Jovian Atmospheric Exploration

- Dynamical structure of a giant gas planet with fast rotation　- Study the cumulonimbus cloud and the thunder storm

- Mysterious composition of the atmosphere

Planetary Magnetosphere Science

Mercury, Earth, Jupiter

Formation observation

Jupiter

MarsMercury

EarthSun

No global magnetosphere: Atmospheric erosion

Gigantic magnetosphere: Particle acceleration

Space is not empty! Solar wind and high energy particles from the sun interact with planetary magnetosphere

Nozomi （ 1998） BepiColombo （ 2013） Jupiter mission (2020)

Small magnetosphere: Unknown parameter regime

Basic Policy of JAXA’s Future Science Mission

Top-level scientific objectives

Originality

Technical feasibility

International missions

Thank you for your attention