Calling taikong a strategy report and study of chinas future space science missions

Science Policy Reports Calling Taikong: A Strategy Report and Study of China's Future Space Science Missions Ji Wu... To beexact, with spacecraft as the main tools, space science is d

Science Policy Reports

Calling Taikong: A Strategy Report and Study of

China's Future

Space Science

Missions

Ji Wu

Science Policy Reports

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Ji Wu

Calling Taikong: A Strategy

Future Space Science

Missions

123

Ji Wu

National Space Science Center

Chinese Academy of Sciences

Beijing

China

ISSN 2213-1965 ISSN 2213-1973 (electronic)

Science Policy Reports

ISBN 978-981-10-6736-5 ISBN 978-981-10-6737-2 (eBook)

https://doi.org/10.1007/978-981-10-6737-2

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As its name implies, space science is the study of space, i.e.,“Taikong” in Chinese,

or more specifically scientific research that has to be carried out in space To beexact, with spacecraft as the main tools, space science is defined as the study ofnatural phenomena and their underlying rules in physics, astronomy, chemistry, andlife sciences which exist in solar-terrestrial space, interplanetary space, and even theuniverse as a whole In October 1957, thefirst man-made satellite “Sputnik” waslaunched Since then, unprecedented new instruments and methods have beendeveloped in order to explore space, and a stream of revolutionary discoveries hasbeen achieved These discoveries have, in essence, revealed a completely newuniverse and profoundly changed our understanding of nature and human beings, aswell as human life itself Einstein predicted that the frontier of natural sciencewould gradually shift to both macro- and micro-forefronts, and current research inspace science is aimed at both the universe in the macroscopic sense, and particlesand the origin of life in the microscopic sense Among them, the search for darkmatter and dark energy, detection of gravitational waves, and so on continues tolead the development of human society, and open up new scientific frontiers.Being highly explorative, the study of space science constantly demands novelinstruments and spacecraft technologies, and the acquisition of new data mainlyrests on the progress of new techniques This trend greatly boosts the development

of space technologies, which also extends to applications, bringing about potentialeconomic benefits Thus, space science has become the main driving force of spacetechnologies and applications It is also one of the major areas which engendersinternational cooperation Thefirst reason to go for international cooperation is thatany discoveries need not to be duplicated It is vital for both the decision makersand scientists to avoid duplication when planning a mission The second reason isthat the number of approved missions is always much less than that of the proposalsdue to the limited funds The scientists’ demands are unlimited, while the gov-ernment’s investment is limited The need to combine financial resources isbecoming more and more pressing because of the increasing size and scope of spaceprograms, and smoothly coordinated programs can often at least double theiroverall output

v

China has launched more than 100 application satellites since 1970 when herfirst man-made satellite—Dongfanghong-1—was successfully launched A rela-tively comprehensive satellite system for various applications has been established,and China has gradually developed into one of the world’s space powers After theliftoff of the “Wukong” mission on December 2015, i.e., DArk Matter ParticleExplorer (DAMPE) satellite whose official delivery to the scientific user was inMarch 2016, and the launch of SJ-10 in April 2016, thefirst Chinese microgravityand life sciences mission, further missions will follow QUantum Experiment atSpace Scale (QUESS) and Hard X-ray Modulation Telescope (HXMT) have beenlaunched successively on Aug 16, 2016, and Jun 15, 2017 Chinese space science isentering its most exciting era However, the existing space science missions gen-erally follow the principle of a case-by-case approval system, lacking a stablefunding system as well as a long-term national program.

In order to advance China’s space science, and provide scientific input andsuggestions for future development and national budget allocation, the NationalSpace Science Center, Chinese Academy of Sciences (NSSC-CAS) has led a study

on future space science programs in China in 2016–2030 supported by the SpacePriority Program (SPP) on space science of CAS The report, one of the results

of the study, is a short version of the original study report in Chinese It consists of

7 chapters The first chapter is the overview Chapter 2 introduces the status ofspace science in China Chapter3poses the scientific questions to be addressed bythe Chinese space science community in 2016–2030, of which the two themes are

as follows: (a) How did the universe and life originate, and how do they evolve?(b) What’s the relationship between the solar system and human beings? Chapter4

is the core of this report The strategic goals, space science programs and missions,the road map through 2030, and the implementation approaches are proposedhereby in the chapter Chapter5 probes into the technologies required Chapter6provides an outlook of space science beyond the year 2030 Chapter7 concludesthe report

List of Main Contributors

Wu Ji, the study team leader, responsible for the main themes, the coordination

of the subtopics, and thefinal review of the report

Sun Lilin, Fan Quanlin, Bai Qingjiang, and You Liang (NSSC, CAS), sible for compiling the report

respon-Zhang Shuangnan, Lu Fangjun (Institute of High Energy Physics, CAS), andChang Jin [Purple Mountain Observatory (PMO), CAS], responsible for preparingthe text in astrophysics

Observatories, CAS (NAOC)], responsible for preparing the text in space solarphysics

Wang Chi and Xu Jiyao (NSSC, CAS), responsible for preparing the text inspace physics.

Zou Yongliao (NAOC) and Li Lei (NSSC, CAS), responsible for preparing thetext in planetary science

Shi Jiancheng (Institute of Remote Sensing and Digital Earth, CAS), Hu Xiong(NSSC, CAS), and Chen Hongbin (Institute of Atmospheric Physics, CAS),responsible for preparing the text in space earth science

Liu Qiusheng, Kang Qi, and Wang Shuangfeng [Institute of Mechanics (IM),CAS]; Pan Mingxiang (Institute of Physics, CAS); and Feng Ji (Beijing AdvancedSciences and Innovation Center, CAS), responsible for preparing the text inmicrogravity science

Zhang Yuanzhong (Institute of Theoretical Physics, CAS), responsible forpreparing the text in space fundamental physics

Long Mian (IM, CAS) and Liu Zhiheng (Institute of Microbiology, CAS),responsible for preparing the text in space life sciences

Meng Xin (NSSC, CAS), responsible for preparing the text in space integratedtechnologies

After the draft compiled, it has been presented to the National Space ScienceCommittee, and valuable advice has been obtained It has also been forwarded to anumber of recognized international scholars affiliated to the institutes and univer-sities in France; Russia; USA; the Netherlands; Italy; UK; Germany; Finland;Belgium; Canada; Hong Kong, China; and Taiwan, China, to review the report,whose suggestions and comments are very helpful and valuable Our heartfeltthanks go to the following scientists, of whom Roger-Maurice Bonnet is the leadreviewer:

Roger-Maurice Bonnet, European Space Agency, France

Lev Zelenyi, Russian Academy of Sciences (RAS), Russia

Cui Wei, Department of Physics, Purdue University, USA

Leonid Gurvits, Joint Institute for VLBI in Europe, the Netherlands

Marco Feroci, High Energy Astrophysics section, Italian National Institute ofAstrophysics, Italy

Kenneth Irwin Kellermann, National Radio Astronomy Observatory, USA.Henry Ferguson, Space Telescope Science Institute, USA

Jean-Claude Vial, Institut d’Astrophysique Spatiale, France

Eduard Kontar, University of Glasgow, UK

Vladimir Kuznetsov, Pushkov Institute of Terrestrial Magnetism, Ionosphereand Radio Wave Propagation of the Russian Academy of Sciences (IZMIRAN),Russia

George K Parks, University of California, Berkeley, USA

Berndt Klecker, Max Planck Institute, Germany

Song Paul, Center for Atmospheric Research, University of Mass Lowell, USA

Ye Yongxuan, Taiwan“Central University,” Taiwan, China

Massimo Menenti, Delft University of Technology, the Netherlands

Marti Hallikainen, Aalto University, Finland

Jean Claude Legros, University Libre de Bruxelles, Belgium

Douglas Matson, Tuffs University, USA.

Alexander Senchenkov, Research and Development Institute for LaunchComplexes (NIISK), Federal Space Agency of Russian Federation, Russia.Christian Eigenbrod, University of Bremen, Germany

Philippe Bouyer, Institut d’Optique d’Aquitaine, France; ESA member of the

“Gravitation Observatory Advisory Group.”

Wang Chen, University of Toronto, Canada

Zhang Ge, Hong Kong Baptist University, Hong Kong, China

Colin Mcinnes, University of Glasgow, UK

This report embodies the viewpoints shared by many space scientists and experts

on future space science development It has also been supported by CAS quarter and its Bureau of Major Research and Development Programs

head-We would like to express our most sincere appreciation to all those who havecontributed to the report

It is expected that the report can further readers’ understanding of space scienceand allow the public to become more interested in it We also hope that it couldprovide input for China’s future space science planning and decision-making andact as a bridge for international cooperation in space science

April 2016

1 Overview 1

2 Status in China 3

3 Scientific Questions 7

4 Strategic Goals and Programs Through 2030 9

5 Technologies 41

6 Development Beyond 2030 45

7 Conclusion 47

Acronyms 49

References 51

ix

Chapter 1

Overview

Since the beginning of 21st century, space science missions have been more andmore frequently implemented, and human beings are increasingly expanding theirdestination into deep space Space science, as a frontier inter-discipline researcharea, has a fantastic nature that it’s closely related to scientific and technologicalbreakthroughs Besides, it is also an area closely related with human survival anddevelopment Therefore, it is playing an increasingly important role in national devel-opment It is also an important area that is highly valued and supported by variousworld powers

With spacecraft as the main tools, the space science is aimed to study natural nomena and the underlying rules in physics, astronomy, chemistry and life science,which occur in solar-terrestrial space, interplanetary space and even the universe as

phe-a whole It explores the unknown rphe-anging from lphe-arge celestiphe-al bodies to fundphe-amentphe-alrules of atomic and molecular science, so as to unveil the physical laws of nature.This makes it an important worldwide frontier of modern natural science Spacescience can be studied from the following sub-disciplines: space astronomy, spacesolar physics, space physics, planetary science, space Earth science, microgravityscience, space fundamental physics and space life sciences

Since 2012, CAS has been supporting a study on future space science missions

in China The project is called “Prospect for Space Science in 2016–2030” led byNSSC, CAS, with over 80 scientists all over the country involved in it The projecthas been completed by mid-2015 As one of the results of the study, the report is theshort version of the original Chinese report, but with most of the important facts andscientific contents

© Science Press and Springer Nature Singapore Pte Ltd 2017

J Wu, Calling Taikong: A Strategy Report and Study of China’s Future Space

Science Missions, Science Policy Reports, https://doi.org/10.1007/978-981-10-6737-2_1

1

Chapter 2

Status in China

After 50 years of development, China has laid a certain foundation in space nology and space science research, also making great progress in discipline devel-opment, research team and infrastructure construction Chinese space science has agreat growing trend, along with its complete disciplines, growing research team andemerging scientific results

tech-With respect to policies, the State Council published a white paper China’s

Space Activities in 2011 in December of that year, specifying purposes and

princi-ples of China’s space industry development: to explore outer space and to enhanceunderstanding of the Earth and the cosmos; to utilize the outer space for peace-ful purposes, to promote human civilization and social progress, and to benefit thewhole of mankind; to meet the demands of economic development, scientific andtechnological development, national security and social progress; and to improve thescientific and cultural knowledge of the Chinese people, to protect national rights andinterests, and to build up its national comprehensive strength China’s space industrydevelopment is subject to and serves the overall national development strategy, andadheres to the principle of scientific, independent, peaceful, innovative, and opendevelopment

With respect to manned space engineering, “Tiangong-1” target spacecraft and

“Shenzhou-8” spacecraft were successively launched in September and November

2011, which made China’s first Rendezvous and Docking (RVD) test a success, andlaid a solid foundation for follow-up construction of the space lab and space station

In June 2012, “Shenzhou-9” spacecraft, carrying male astronauts Jing Haipeng, LiuWang, and female astronaut Liu Yang, carried out RVD with “Tiangong-1” success-fully, which was the first manned space RVD test in China In June 2013, manned

by male astronauts Nie Haisheng, Zhang Xiaoguang, and female astronaut WangYaping, “Shenzhou-10” spacecraft was successfully launched by LM-2F rocket Alecture was given by Chinese astronauts in space for the first time The spacecraftreturned to the Earth safely after a 15-day in-orbit flight

With respect to the lunar exploration program, China successfully launched

“Chang’e-2” lunar probe in October 2010, which acquired higher-resolution images

© Science Press and Springer Nature Singapore Pte Ltd 2017

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Science Missions, Science Policy Reports, https://doi.org/10.1007/978-981-10-6737-2_2

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4 2 Status in China

Fig 2.1 The lander and the

rover of “Chang’e-3” take

photos of each other

successfully Credit China

National Space

Administration

of the full moon and the Sinus Iridum Research was done with these images on themoon’s topography, geology, surface composition, microwave characteristics, near-moon space environment, etc A number of extended experiments were carried outsuch as those orbiting L2, etc., which laid a foundation for the subsequent deep spacemissions In December 2013, “Chang’e-3” lunar probe was successfully launched.The lunar lander and “Yutu” rover, performed soft-landing and lunar surface patrol.Besides, the lander and the rover took photos of each other (Fig.2.1) They performed

in situ analysis of the lunar surface characteristics, topography and integrated geology

of the landing and patrolling areas The detection of the lunar surface and lunar-basedastronomical observation were also carried out, fulfilling the goal of the second step

of lunar exploration In October 2014, Chang’e-5-T1, a Chinese precursor missionfor the Chang’e-5 lunar sample return mission, was launched, and the successfulflight validated the technology for the reentry vehicle

With respect to space science satellites, the most important all-round progress in

China’s space science since 2010 is the start of the Strategic Priority Program (SPP)

on Space Science led by CAS In March 2010, at the 105th executive meeting, the

State Council approved 2020 Innovation Plan submitted by CAS It requested CAS

to “organize the implementation of the Strategic Priority Programs to make majorinnovative breakthroughs and strive for competitive advantages in various aspects”

In January 2011, at the meeting of CAS leaders, it was decided to launch the first

of the Strategic Priority Programs Thus, the SPP on Space Science entered into itsformal implementation phase The go-ahead of the Program marked that China’sspace science had entered a new stage

The overall goal of SPP on Space Science is as follows: in the scientific tiers with the greatest potentials for scientific discoveries where we have the mostadvantages, through both independent science missions and international coopera-tion, to achieve major scientific breakthroughs, then to subsequently drive the greatleaps of related advanced technologies, and to enable the strategic role of spacescience in national development The Program includes strategic planning of space

fron-2 Status in China 5

Fig 2.2 The block diagram of SPP on space science Credit CAS/NSSC

science development, the research on innovative concepts and the pre-study of theirrelated technologies, the development of key technologies concerning space sciencesatellites, the satellites’ development, launch and operation as well as the scientificdata analysis This mainly constitutes the complete chain of a space science mission,from incubation, beforehand preparation, key technology R&D, through to engineer-ing development and final outputs Figure2.2shows the structure of SPP on SpaceScience

Chapter 3

Scientific Questions

China’s space science research will focus on the following two themes through 2030

Theme one: How did the universe and life originate, and how do they evolve? Theme two: What’s the relationship between the solar system and human beings?

Theme one involves the following scientific questions:

(a) How did the universe originate, and how does it evolve?

• What is the universe made of, and how does it evolve?

• What are the origins of the structures and objects of different scales in theuniverse, and how do they evolve?

• Is there any new physics beyond the current basic physics theories?

(b) How did life originate, and how does it evolve?

• How did life originate, and how does it evolve?

• Acquire evidence of life elsewhere

(c) What are the kinetic properties of matter, and what is the rule of life activity inthe space environment?

• What are the kinetic properties of matter in the space environment?

• What is the rule of life activity in the space environment?

Theme two involves the following scientific questions:

(a) What is the nature of solar activities?

• What is the nature of solar micro-phenomena?

• What is the nature of solar macro-phenomena?

© Science Press and Springer Nature Singapore Pte Ltd 2017

J Wu, Calling Taikong: A Strategy Report and Study of China’s Future Space

Science Missions, Science Policy Reports, https://doi.org/10.1007/978-981-10-6737-2_3

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8 3 Scientific Questions(b) What is the origin and evolution of the solar system, and its relationship withthe Sun?

• How did the planets in the solar system originate, and how do they evolve?

• How does solar activity transmit and evolve in interplanetary space?

• How does solar activity affect the Earth space environment?

(c) How does the Earth system evolve?

• How did the Earth system change?

• Why did the Earth system change?

• How will the Earth system change?

• How will the Earth system science advance to adapt itself to global changes?

Chapter 4

Strategic Goals and Programs Through 2030

4.1 Strategic Goals Through 2030

The overall strategic goal of China’s space science through 2030 is to: (a) makegreat scientific discoveries and achieve breakthroughs through a series of scientificsatellite programs and missions in scientific frontiers These include the formationand evolution of the universe, the search for exoplanets and extraterrestrial life, theformation and evolution of the solar system, solar activities and their impact on theEarth’s space environment, the development and evolution of the Earth’s system,the new physics beyond the current basic physics theories, the kinetic properties ofmatter, and the rule of life activity in space environment (b) Drive the great leaps ofspace technology and other related technologies We’re devoted to make contribution

to exploring the unknown The phased goals are as follows

Through 2020, the four scientific satellites approved during the “12th Year Plan” (2011–2015) period, i.e DAMPE, SJ-10, QUESS, and HXMT, will

Five-be launched, and five to six new scientific satellites will Five-be approved and oped They are expected to make significant scientific discoveries and achievebreakthroughs on black holes, dark matter, time-domain astronomy, magnetosphere-ionosphere-thermosphere coupling, global change and water cycle, fundamental the-ories of quantum physics, kinetic properties of matter, and the rule of life activity inspace environment, etc In addition, new advanced research missions and intensivestudy missions will be arranged, to prepare for scientific satellites to be approved dur-ing the “14th Five-Year Plan” (2021–2025) and “15th Five-Year Plan” (2026–2030)periods

devel-Through 2025, the satellites approved during the “13th Five-Year Plan” period(2016–2020) would be launched, and six to seven scientific satellites would beapproved and developed They are expected to make significant scientific discov-eries regarding physical rules under extreme conditions, the physical nature of blackholes and neutron stars, the search for exoplanets, the Sun’s magnetic field and itseruption, propagation rules of Coronal Mass Ejections (CMEs), solar-terrestrial spaceenvironment, near-earth space and global changes, and so on

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10 4 Strategic Goals and Programs Through 2030Through 2030, the satellites approved during the “14th Five-Year Plan” periodwould be launched, and seven to eight scientific satellites would be approved anddeveloped They are expected to make significant scientific discoveries regardingthe early-stage evolution of the universe, the extreme astrophysics, the detection ofgravitational waves and the measurement of solar vector magnetic field, etc.

4.2 Space Science Programs

To answer the scientific questions mentioned above, a space science plan with specificgoals and technical feasibility is necessary Up to 2030, in view of China’s spacescience status and its technical capabilities, Table4.1lists the scientific programsand missions proposed to address these questions

4.2.1 Black Hole Probe (BHP) Program

Through observations of compact objects such as black holes and gamma-ray bursts,this program aims to study high-energy processes of cosmic objects and the black holephysics, and explore the extreme physical processes and laws in the universe withextreme objects such as black holes as probes of how stars and galaxies evolve BHPProgram mainly focuses on the significant scientific questions about the universe’sformation and evolution, including: (a) what is the nature of extreme and compactobjects like black holes? (b) How do these objects interact with their surroundingenvironments? (c) What are the physical rules of compact objects, strong magneticfields and extreme gravitational fields? (d) How do the super massive stars evolveand develop into compact objects like black holes? (e) How do the super massiveblack holes form and grow? (f) What is the role of super massive black holes inthe formation and evolution of galaxies and macro-scale structures in the universe?(g) How does dark matter and dark energy evolve in the high red-shift universe?Major missions proposed BHP include HXMT, Space Variable Objects Monitor(SVOM), and gamma-ray burst polarization experiment (POLAR) HXMT, has beenlaunched in Jun 15, 2016, mainly aims to: (a) perform repeated scanning surveys ofthe galactic plane, in order to monitor galactic variable sources and to detect newgalactic transient sources (b) Make large-area sky observations, in order to studythe cosmic variance of the cosmic X-ray background (c) Obtain the broad bandX-ray spectra of bright AGNs, in order to constrain the geometry of the variouscomponents in the AGN unified model (d) Observe X-ray binaries with broad-band spectral and timing capabilities, in order to understand the physics under theextreme physical conditions near compact objects (Fig 4.1) SVOM focuses onanswering scientific questions concerning the early evolution of the universe It isdedicated to the discovery and fast positioning of all known types of gamma-raybursts, as well as the comprehensive measurement of their electromagnetic radiation

4.2 Space Science Programs 11

12 4 Strategic Goals and Programs Through 2030

4.2 Space Science Programs 13

14 4 Strategic Goals and Programs Through 2030

4.2 Space Science Programs 15

Fig 4.1 An artist’s view of HXMT in orbit Credit HXMT mission team/CAS SPP on Space

Science

It will also explore the objects formed in the early stage of the universe, and studythe early evolution of the universe and the macro-nature of dark matter and darkenergy POLAR, to be aboard on the Chinese space lab “Tiangong-2” (TG-2),1will

be the first high-sensitivity scientific instrument specialized in measuring gamma-raypolarization of gamma-ray burst

4.2.2 Diagnostics of Astro-Oscillations (DAO) Program

For celestial bodies in the universe, the change of their electromagnetic ation signals with time provides the basic information of their internal struc-tures and activities The periodic light variability of stars, white dwarfs, andneutron stars plays a vital role in our understanding of their nature DAO Pro-gram aims to make high-precision photometric and timing measurements ofelectromagnetic radiation at various wavebands and non-electromagnetic radia-tion (such as gravitational waves), in order to understand the internal structures

radi-of various astrophysical objects and the processes radi-of various violent activities.Major missions proposed include X-ray Timing and Polarization (XTP), Ein-stein Probe (EP), China’s Gravitational Wave Detection Program, and Neutron-star Extreme Astrophysics and new Technology Exploration Research (NEATER),

a mission proposed to be aboard on the Chinese space station XTP (Fig 4.2)aims to observe black holes, neutron stars and magnetars, and investigate GeneralRelativity under extreme gravity, neutron star’s state under extreme density, and

1 “Tiangong”, which literally means “palace in the sky” in Chinese, is the palace where the Jade Emperor and fairies live.

16 4 Strategic Goals and Programs Through 2030

in extreme physical conditions of strong gravity China’s Gravitational Wave tion Program, which mainly includes Taiji mission, Tianqin mission, Ali mission andthe participation in European eLISA program (with Chinese payload contribution nomore than 20% of the total budget) The main scientific goal of Taiji project is toobserve gravitational wave from mergence of binary black holes or great massivecelestial bodies and so on Tianqin mission will observe gravitational wave from

Detec-a super compDetec-act white dwDetec-arf with Detec-a period of 5.4 min Ali mission Detec-aims to probeprimordial gravitational waves, the lowest frequency gravitational waves sourcedfrom the perturbations of space-time during accelerating expansion of our universe

at the very beginning, the so called inflation, and it will be the first high-sensitivitytelescope for observing polarization of cosmic microwave background radiation innorth hemisphere NEATER’s main scientific topics are neutron stars, pulsar timing,extreme gravity/density/magnetism, accretion disks, and jets At present, XTP and

EP have both been in the intensive study phase in the framework of SPP on SpaceScience

4.2 Space Science Programs 17

4.2.3 Portraits of Astrophysical Objects (PAO) Program

PAO Program aims to directly acquire the portraits of stars, planets, white dwarfs,neutron stars and black holes beyond the solar system, and high-resolution pictures

of the central regions of galaxies, star formation regions, supernova remnants, as well

as jets It will survey the sky in various bands using deep imaging, and also providehigh-resolution maps of the sky with background radiation at different wavebands.All of these will play a vital role in addressing scientific questions such as: what is theuniverse made of? Major missions proposed include Space millimeter-wavelengthVLBI Array (S-VLBI) and Space Ultra-Low Frequency Radio Observatory (SUL-FRO) S-VLBI (Fig.4.4), through the construction of ultra- high-resolution spacemillimeter wave VLBI array, observes compact objects such as black holes throughimaging their extremely fine structures so as to reveal the physical processes aroundblack holes, and address the frontier questions such as what the physical nature

of black holes is At present, S-VLBI has been in the intensive study phase in theframework of SPP on Space Science SULFRO will feature unprecedented imagingcapability with high resolution and high sensitivity, to make major discoveries in thefrontier fields of astrophysics and fundamental physics such as exploration of theuniverse’s Dark Age, exoplanet search, CMEs, and galaxy formation

4.2.4 Spectroscopy of Astrophysical Objects (SAO) Program

SAO Program will measure the spectra of celestial objects with high resolution atvarious wavebands (main bands: visible, radio and X-ray), to understand the chemicalcomposition, density and temperature of various kinds of celestial objects, as well as

to determine their distances (radial velocities), sizes, masses, densities and velocities.This is in order to study their physical processes and structure models at differentscales and locations, measure gamma-rays, electrons and cosmic rays with highenergy resolution, and to understand the properties of dark matter and the origin

of cosmic rays Major missions proposed include UltraViolet Emission Mapper of

“Cosmic Web” (UVEM), COsmology and Molecule Explorer (COME), DAMPE

18 4 Strategic Goals and Programs Through 2030satellite, China’s Space Station Optical Survey (CSSOS), High Energy cosmic-RayDetector (HERD) and X-ray all sky monitor Among them, CSSOS, HERD, andX-ray all sky monitor are proposed to be aboard on the Chinese space station UVEMplans to detect HI and OVI emissions around 300 nearby galaxies Stereo imaging ofemission lines of Lyα and OVI in intergalactic medium can unveil the extended gas at

the intersections of filaments (dominated by accretion and galactic wind), in galaxyhalos, galaxy groups and clusters of galaxies The main science goal of COME is

to trace the cosmological evolution from dark to light, and to search for new gascomponent in the universe The main scientific goals of DAMPE (Fig.4.5) are to:(a) detect high energy electron and gamma-ray spectra with high energy resolutionand wide energy range, and make breakthroughs in the field of dark matter search.(b) Detect electrons and heavy nuclei beyond 1 TeV, and answer the question aboutthe origin of cosmic rays (c) Carry out high energy gamma-ray survey DAMPE,also called “Wukong”, was lifted off on December 17, 2015 CSSOS would carryout a wide range of studies including, for example, (a) precise determination ofthe cosmological parameters, dark energy equation of state, neutrino masses, anddark matter particle properties (b) Detailed examination of the cosmological model,gravity properties on cosmic scales, and the theory of hierarchical structure formationand evolution (c) Reconstruction of the initial density perturbations of the universeand the three-dimensional galactic structure and its formation history (d) And itwould shed light on how stars, black holes, and galaxies form and evolve Herdwill cover a wide energy range from hundreds of GeV up to PeV (for cosmic rays)with precise spectrum measurement, in order to solve the puzzle of the origin of theGalactic cosmic rays The main science topics of the X-ray all sky monitor are X-raybinaries, supernovae, gamma-ray bursts, active galactic nuclei, and tidal disruption

of stars by super massive black holes

Fig 4.5 An artist’s view of DAMPE satellite in orbit Credit DAMPE science team/CAS SPP on

Space Science

4.2 Space Science Programs 19

Fig 4.6 Illustration of

STEP satellite in operation.

Credit STEP science

team/CAS SPP on Space

Science

4.2.5 ExoPlanet Exploration (EPE) Program

EPE program aims to: (a) search for and characterize Jupiter-like, Earth-twin planets beyond the solar system (b) Measure precisely and analyze systematically thecritical physical parameters of exoplanets including mass, orbit, and radius (c) Buildthe database about important physical parameters like planet radius, density, effectivetemperature, albedo, atmospheric environment, greenhouse gas and surface gravity.(d) Address the question “whether there is another Earth in the universe” Major mis-sions proposed include Search for Terrestrial ExoPlanets (STEP), Jupiter/Earth-twinExoplanets and Exo-zodiacal Dust Imager and Spectrometer (JEEEDIS), Search-ing for habitable Earth-New Earth (Nearth) STEP (Fig.4.6) focuses on the frontierstudy of terrestrial planets It will precisely detect the exoplanet systems near thesolar system, to search for terrestrial exoplanets nearby, and to perform calibration

exo-on cosmic distance At present, STEP has been in the intensive study phase in theframework of SPP on Space Science JEEEDIS mainly focuses on the search forterrestrial and Jupiter-like exoplanets It observes and quantitatively analyzes theExozodiacal Dust (ED) located within 20 pc,2Jupiter-like exoplanets (mature plan-ets whose semi-major axis of the orbit is 0.4–5 AU and whose effective temperatureranges from dozens of Kelvins to hundreds of Kelvins), and terrestrial exoplanetswithin habitable zones Nearth mainly searches for terrestrial exoplanets in habitablezones with occultation It also searches for bright exoplanets (especially terrestrialexoplanets in habitable zones), and studies the optical viability of bright stars andasteroseismology

4.2.6 Solar Microscope Program

By observing the Sun with high spatial resolution and multiple frequencies, SolarMicroscope Program aims to study the basic physical processes, such as the solarinner structure evolution, the origin of magnetic fields, the coronal structure and

2 “pc” is short for “parsec”.

20 4 Strategic Goals and Programs Through 2030dynamics, and to trigger mechanisms of solar bursts and particle acceleration mech-anisms It intends to answer a series of major questions such as the nature of magneticelements, the small-scale magnetic characteristics, the energy process of solar flares,the characteristics of CME source region, etc Major missions proposed include Deepspace Solar Observatory (DSO), Solar Polar Region Explorer (SPORE), Super HighAngular Resolution Principle for coded-mask X-ray imaging (SHARP-X) and Multi-layer Exploration of Solar Magnetic and Velocity field (MESMV) The scientific goal

of DSO is to study solar local magnetic structures with high accuracy and high spatialresolution of 0.1–0.15 arcseconds This is expected to achieve major breakthroughs

in solar physics through accurate observation of magnetic elements, together withobservations at multiple frequencies, so as to provide an important grounding inphysics and new methods for space weather forecasting SPORE mainly focuses onthe scientific questions about solar eruption mechanism It will operate in a solarpolar orbit, to observe, for the first time, the magnetic field in solar-pole regionsand its velocity field through spectral and imaging observations, so as to unveil themechanism of solar activity cycle and understand the origin of high-speed solarwind SHARP-X will observe the Sun in hard X-rays with a spatial resolution ofsub-arcseconds for the first time, and study the structure, evolution, accelerationand transportation mechanism of energetic particles in solar flares MESMV aims toobtain the information of the solar magnetic field and the velocity field at differentlayers, advance our understanding of the transfer and evolution of substances andmagnetic energy from the bottom of the photosphere to the corona, so as to makegreat breakthroughs in physical studies concerning solar eruption mechanism andsolar active region, as well as to provide physical basis and new methods for spaceweather forecasting

4.2.7 Solar Panorama Program

Besides the high spatial resolution study for the Sun, Solar Panorama Program willpay more attention to the global behavior of the Sun, by multi-waveband diagnos-tics, to explore a physical connection between small-scale motion and the large-scaleconsequences This program tries to answer a series of major questions, such as theorigin of magnetic fields, the properties of the large-scale magnetic field, the proper-ties of flares and their relationship with CMEs, the global properties of the CMEs, and

so on Major missions proposed include Advanced Space-based Solar Observatory(ASO-S), Solar Radio Array at extremely Low Frequency (SRALF), StereoscopicPolarization Imagers for Explosive Sun (SPIES), Solar Energetic Emission and Par-ticle Explorer (SEEPE) and Large Area Solar Gamma-ray spectrometer (LASGA),

a mission proposed to be aboard on the Chinese space station ASO-S (Fig 4.7)mainly focuses on frontier studies on solar magnetic fields and solar eruptions inorder to unveil the inter-relationship among solar flares, CMEs, and solar magneticfields and their formation rules At present, ASO-S has been in the intensive studyphase in the framework of SPP on Space Science SRALF will fill the gap of extreme

4.2 Space Science Programs 21

Fig 4.7 Illustration of

ASO-S satellite in operation.

Credit ASO-S science

4.2.8 Space Weather Chain Program

Space Weather Chain Program focuses on the key coupling processes in the terrestrial space It studies the whole process and basic physics of formation, release,transfer, conversion and consumption of the energy for large-scale disturbances

solar-in space weather events, solar-in order to understand the mechanisms of how the tromagnetic solar radiation and high-energy particles impact the global climatechange Major missions proposed include KUAFU, Magnetosphere-Ionosphere-Thermosphere (MIT) Coupling Constellation Mission, and Solar Polar ORbit Tele-scope (SPORT) KUAFU will: (a) Perform integrated, continuous, multi-layeredlong-term observation of the origin of solar wind and CME eruptions (b) Determinethe earthward velocity and energy output of these disturbances (c) Track their prop-agation and evolution in interplanetary space, and solve systematically the problem

elec-of what drives space weather (d) Improve the quality elec-of forecasting space weatherhazard MIT mission (Fig 4.8) is targeting the coupling processes of the Earth’smagnetosphere-ionosphere-thermosphere system The mission’s science objectivesfocus on the acceleration mechanism and the origin of upflow ions and other relatedscientific questions SPORT (Fig.4.9) will observe CMEs, solar high-latitude mag-netism, and the fast solar wind from a polar orbit around the Sun It would provide aunique opportunity to study CME propagation through the inner heliosphere from a