太空|TAIKONG ISSI-BJ Magazine - No. 18 April 2020 - The International Space Science Institute
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太空|TAIKONG
国际空间科学研究所 - 北京 ISSI-BJ Magazine
No. 18 April 2020
IMPRINT FOREWORD
太空 | TAIKONG The relevance of CubeSats for education the basis of its principles of international
ISSI-BJ Magazine as well as for the investigation of collaboration and interdisciplinary
License: CC BY-NC-ND 4.0
unanswered scientific questions in an research. For this purpose, well-known
agile and convenient way has steadily experts were invited to share their
risen in the past decade, providing many profound experiences and valuable
more opportunities for advancement thoughts and insights to train students
Address: No.1 Nanertiao, in space science studies as well as for and researchers from member states on
Zhongguancun, the training of the next generation of the use of small satellites, and for the
Haidian District,
scientists and engineers. joint forum to discuss key scientific tools
Beijing, China
that can be developed for CubeSats
Postcode: 100190
Phone: +86-10-62582811
Given the numerous possibilities and science missions.
Website: www.issibj.ac.cn the great advantages deriving from the
sharing of know-how and knowledge During three days, the APSCO training
of these small satellites, CubeSats- course engaged 16 international
based international and interdisciplinary students from its member states, who
Authors
collaboration currently assume a great finally joined 14 leading scientists from
significance for the promotion of cross- 10 countries at the brainstorming forum
See the list on the back cover
country cooperation on joint studies and inaugurated on June 6, 2019. The event
space missions. And it is exactly for all was thus attended by a total of 40
these reasons that the APSCO training scientists and engineers from numerous
Editor course on CubeSats as well as the forum countries, including Bangladesh, China,
on “Science Missions using CubeSats” Denmark, Finland, Germany, Iran, Italy,
Laura Baldis,
were convened by Mohammad Ebrahimi Japan, South Korea, Mongolia, Pakistan,
International Space Science
Institute - Beijing, China
Seyedabadi (APSCO, China) and Peru, Switzerland, Thailand, and Turkey.
Maurizio Falanga (ISSI-BJ, China) from
June 3 to June 7, 2019, in Thailand. The opening ceremonies were held in the
morning of June 3, 2019 (Training), and
The Asia-Pacific Space Cooperation June 6, 2019 (Forum), at the Auditorium
Organization (APSCO), as a multilateral of Sirindhorn Center for Geo-Informatics
inter-governmental organization, (SCGI) located in the Space Krenovation
FRONT not only promotes regional space
cooperation, but also enhances the
Park (SKP). They were inaugurated by Dr.
Aorpimai Manop, Director General of
COVER capacity building of its member states Department of Strategic Planning and
in different disciplines. Such goal was Program Management of APSCO; Prof.
perfectly coupled with ISSI-BJ's efforts Maurizio Falanga, Executive Director of
CubeSats
to advance space science studies on ISSI-BJ; Mr. Pierre Hagmann, Embassy of
Image Credit: Universe Today
2 太空|TAIKONG
Switzerland in Bangkok, and Dr. Tanita Suepa, a special slot for students’ presentations and
Chief of Instructional Media and Curriculum discussions was ensured.
Development Division of GISTDA, Thailand.
The training program provided an overview of The two events were successfully concluded
the importance, current practices, and future on June 7, 2019. During the final ceremony, Dr.
perspectives for “Science Missions using Aorpimai Manop and Prof. Maurizio Falanga
CubeSats” and the different generic categories gave the concluding speech and provided
of instruments used to monitor space weather a summary of the Forum. A cultural tour was
from the ground. The experts Dr. Qamarul organized on June 8, which left the participants
Islam (Institute of Space Technology, IST), Dr. deeply satisfied with the content of the events
Martin Langer (Technical University of Munich, as well as the arrangement of the leisure
Germany), Dr. Muhammad Rizwan (Institute of activities.
Space Technology, Aalto University, Finland),
Prof. Leonardo Reyneri (Politechnico di It comes without saying that the two activities
Torino, Italy), and Prof. Yu Xiaozhou (Shanxi provided brilliant insights, deep knowledge-
Engineering Laboratory for Microsatellites) sharing, and unprecedented networking
kindly contributed to this training program. opportunities to all participants, from the
students to the teachers, much of which will be
The Forum section, which began on June 6, presented in this Taikong magazine issue.
successfully managed to reduce the distance
between trainees and the scientific community,
that gave them the opportunity to hear new
ideas and be motivated towards a carrier in Mohammad Ebrahimi Seyedabadi,
this field. After a brief introduction to ISSI-BJ,
APSCO, and to the Forum, the participants
were introduced to the history of CubeSats,
to COSPAR Roadmap on Small Satellites for Director-General
Space Science, as well as the APSCO’s current
Department of Education and Training
and future plans to use Cubesats as a tool for
capacity-building and university cooperation. APSCO
The first day of the Forum ended with a dinner
that enabled the participants to enrich their Maurizio Falanga,
social network and continue their discussions
in a less formal environment.
The second half of the day was devoted to the Executive Director
topic of using CubeSats for space sciences.
ISSI-BJ
After the talks given by international scientists,
太空|TAIKONG 3
1. INTRODUCTION
Since their inception, CubeSats have enjoyed such satellites can efficiently help overcome the
widespread acceptance in the space science difficulties implied by a small research budget
community, currently featuring a growing and little or no experience in the field of space
developer list. In fact, CubeSats can help technology. Small satellites thus represent an
reduce the costs of technical developments ideal opportunity for students, engineers, and
and scientific investigations, therefore lowering scientists in different disciplines — including
the entry-barriers to organizing space missions. software development for on-board and ground
As a result, CubeSats’ popularity in countries computers, engineering, and management
with less resources to be devoted to space of sophisticated technical programs — to
science has grown exponentially in the past few work together on the agile development and
years, adding enormous value to education, operation of space missions. In fact, as the
researchers’ experience, and collaborative ‘build-to-operations’ cycle for CubeSats is less
relationships. than three years, this allows university students
to be involved in its development from its
As of April 2018, over 800 CubeSats have been inception to the operating mission.
launched worldwide, and for some countries
this represented a considerable milestone, as For these reasons and in order to provide vital
for some it meant the very first national satellites training and brainstorming ideas to the current
sent into space. Producing one’s own satellites as well as to the next generation of space
is evidently considered a national achievement experts, the Asia-Pacific Space Cooperation
and a source of national pride by each country, Organization (APSCO) and the International
and coupled with realistic and focused goals, Space Science Institute-Beijing (ISSI-BJ), have
Figure 1: CubeSats - Picture credits: NASA
4 太空|TAIKONG
respectively organized the Training course the nowadays relatively limited but increasing
and the forum on “Science Missions using application of these technology in science. The
CubeSats”, whose main aim was to identify forum tried to follow this concept, suggesting
suitable key sciences to be employed in that CubeSats embrace the technology
CubeSats science missions as well as CubeSat that could potentially lead to breakthrough
feasibilities for space development countries. discoveries.
Furthermore, the goals included also the The answers to the questions on how to design
development of a CubeSats space education a CubeSat, why CubeSats are needed, and
system to establish cooperative programs what is most important for a space mission can
not only for the purpose of training, but also be all summarized in the fact that, according
envisioning a collaboration based on scientific to the specificities of a mission, a personalized
or application missions. manpower capability, mission-related financial
resources, as well as a targeted organization
Specifically, the two-day forum aimed to: management strategy are required.
• identify suitable key sciences that can When it comes to the rationale behind the
be developed for CubeSats science launch of a CubeSat, a good and stable team
missions: What are the CubeSat s' represents an essential factor, together with a
feasibilities for space development sound knowledge of CubeSat development
countries?; engineering, subsystems of a CubeSat as well
as of the experiments targeted. Last but not
• develop CubeSats space education least, it is critical to be familiar with some other
systems to establish cooperative important elements of the mission, such as the
programs not only for the purpose launcher, frequency allocation, law, import and
of training, but also in view of the export regulations.
prospective collaboration in scientific or
application missions; As a result of these reflections and observations
on CubeSats, in the present magazine the
• explore the reports from the training discussions held during the forum have been
section. summarized in four main sections, i.e. the
presentations given by the participants, the
The organization of forums such as the main takeaways acquired on the topic, the
one discussed here can create a fertile soil recommendations of researchers, engineers,
for scientist, engineers, and institutions to and scientists to newcomers in the field, and
combine their expertise with the goal of the relevance of international collaboration for
growing ambitious ideas. The synergy between the development of CubeSats-based missions
communities is the key to advertise and as wells as for an enhances international
improve CubeSats’ capabilities, expanding equilibrium.
太空|TAIKONG 5
2. SCIENCE MISSIONS USING CUBESATS
2.1. Presentations and Analysis
The presentations elaborated during the the mission with the world is the key to creating
forum concerning CubeSat activities were the perfect environment to achieve great
highly country- and/or affiliation-focused. scientific discoveries.
Three primary types of talks could be identified
(with some occasional overlapping between Modularity as well as relatively low costs
categories), i.e.: make CubeSats a great opportunity for
institutions interested both in the scientific
1. physics-oriented; and engineering goals achievable with these
small satellites’ technology, that is already
2. technology-driven; leading to the increase of small satellites
developers. Compared to large satellites, small
3. education-driven; satellites entail low development costs and
offer the opportunity to carry out scientific and
4. science-driven. technological tests over a short period of time.
CubeSats should be built on a close, synergistic Last but not least, in recent years small satellites
and interdisciplinary collaboration between have also become a tool used to train students
space scientists, engineers, and the space and give them a general understanding of
industry, tied up by the cross-fertilization and satellite systems.
encouragement based on the realization of
experiments, cost-containment and operations’ In the light of CubeSats' characteristics and
timing. This way forward will be achieved by their application potential, a review of the four
exploiting at most the Commercial off-the- approaches to CubeSats' studies which took
shelf (COTS) components, currently under- shape during the Forum is presented in the
performing in the space environment, but following sub-chapters.
with the potential to provide high-impact and
radical transformations in space application
Ambitious CubeSats projects must be based on
international collaboration between institutes,
national space agencies, as well as private
companies. Sharing the scientific concepts of
6 太空|TAIKONG
2.1.1. Physics-oriented analysis
"CubeSats for Science Missions" from a physics possibilities in space science missions. With
point of view: What can we do and when? a fixed-mass budget mission designer it may
be possible to aim at a variety of mission
The answer to the usage of CubeSats for approaches. The available mass may be split
Science Missions from a different perspective, up into many small identical units and these
i.e. the one of physics, was advanced by Prof. units may act as a swarm and cover a larger
Fléron, from the National Space Institute at area or volume than a monolithic spacecraft
the Technical University of Denmark (DTU of equivalent mass. Alternatively, a fraction of
Space), Kgs. Lyngby, Denmark, based on the mass budget could be reserved for small
the results yielded from the COSPAR report advanced probes that could extend the base-
“Small satellites for space science - A COSPAR line or reach of a larger spacecraft. The probes
scientific roadmap” [10] and from the work may even be expendable allowing for more
on mass reduction rates for space crafts as daunting missions. be 2 illustrates the different
presented at the IAA-CU-17 in Rome “Will mission scenarios using CubeSats.
CubeSats introduce a Moore’s law to space
science missions” [3]. A typical argument against small spacecrafts
is that the aperture size dictates the resolution
As spacecraft subsystems become smaller, of detectors. From the Fraunhofer diffraction
advanced studies may be performed with theory in the equation below, it is evident that
ever-lighter spacecrafts. This opens up new a way around this issue is to go closer.
α is the angular resolution of a telescope
with aperture size D, whereas λ represents
the wavelength of the observed light. As
an example, the resolution of the Hubble
space telescope and a 3U Dove satellite
from the Planet Labs Inc is compared.
Figure 3 shows the resolution vs distance
for both spacecrafts, with Didymos as a
target example. Didymos closest approach
to the Earth (and Hubble space telescope)
is roughly 10-2 AU or 1.5 million km. As seen
Figure 2: Illustrations of mission scenarios using
CubeSats
太空|TAIKONG 7
Figure 3: Optical resolution at 550 nm as function of distance for the Hubble space
telescope and a Dove satellite from Planet Labs Inc.
the Dove satellite will surpass the best-case
resolution of Hubble space telescope when
the Dove spacecraft is closer than ~2*10-4 AU
or 30,000 km. P0 is the mass required for a certain performance
at time 0, Pt is the mass required for the same
The study “Will CubeSats introduce a Moores performance at time t, n is the reduction rate.
law to space science” [3] looks at the mass The study showed mass reduction rates of
evolution of spacecrafts over time and it refers approximately 127 months (10.5 years) prior
to the analysis of the capability and mass of to the introduction of CubeSats and a rate of
similar class missions, used as a figure of merit. 36 months for Earth observation satellites after
In other words, the mass required to obtain a the CubeSats have appeared. A much smaller
certain performance is calculated for historic study conducted on beep sats, i.e. satellites
missions, but not all mission classes that were that only emits a beacon, showed a mass
studied revealed a mass evolution similar to reduction rate of 55 months.
Moore’s law. However, the Earth observation
missions operating in the optical band did
show a mass reduction tendency similar to
Moore’s law. The equation below shows the
relation.
8 太空|TAIKONG
2.1.2. Science-driven projects
One of the approaches adopted to enter into • Temporal and spatial variations of
space science is to answer science questions plasma trough during magnetic storms;
with already available technologies, thus
putting quite an emphasis on answering • Temporal and spatial variations of
science questions. electron density and temperature in
polar cap patches;
The SNIPE (Small scale magNetospheric and
Ionospheric Plasma Experiment) mission for • Measuring length of coherence for
space weather research developed by the bubbles/blobs;
Solar and Space Weather Group, KASI, Korea,
is going to be launched in 2021 into a polar • EMIC waves at the top of ionosphere.
orbit at an altitude of 500 km with an orbital
high-inclination of (97.7°). The scientific goal Last but not least, this mission constitutes a
of SNIPE is to identify temporal and spatial beautiful example to have a synergy with other
variations of small-scale plasma structures in already existing space weather missions, such
ionosphere and magnetosphere. as THEMIS, MMS, ERG, and GOES as well as
ground observations like EISCAT and CARISMA
SNIPE consists of four 6U-nanosatellites (~ 10 networks.
kg for each spacecraft). This constellation is
a formation flying, and slowly separated from The University of Cagliari, Department of
tens to several hundreds of kilometers for six Physics, Italy, proposed a science-driven
months, and the spacecraft design lifetime is motivated swarm CubeSat mission. With
at least greater than one year (with a scientific the first detected Gravitational Waves event
operation time of six months). The SNIPE (August 2017, GW170817) from merging
mission is equipped with scientific payloads, Neutron Stars - or merging of a Neutron Stars
which can measure the following geophysical with a Black Hole, related to a short Gamma
parameters: density/temperature of cold Ray Burst (GRBs), a new astrophysics era
ionospheric electrons, energetic (~ 100 keV) has started, the so-called Multi-Messenger
electron flux, and magnetic field vectors. All Astrophysics. The operation of an efficient
the payloads will have high temporal resolution X-ray all-sky-monitor with good localization
(better sampling rates than 10 Hz). capability will have a pivotal role in the next
decade on multi-messenger Astrophysics. The
The science targets are: mission submitted, called High Energy Rapid
Modular Ensemble of Satellites (HERMES),
• Spatial scale and energy dispersion of aims to detect and accurately localize GRBs
electron microbursts; and other high-energy transients, such as
太空|TAIKONG 9
Figure 4: HERMES mission - Credits: hermes.dsf.unica.it
the counterparts of GW events (merging of astrophysics of high-energy transients can lead
compact objects, supernovae), that can be to breakthrough discoveries in at least other
deployed in a few years, thus bridging the gap four broad areas:
between the aging, past generation of X-ray
monitors (Swift, INTEGRAL, Agile and Fermi) a) GRB inner engines;
and the next ones.
b) GRB jet composition;
Arcmin localization of most GRB with flux of a
few photons/cm2/s is therefore the final goal of c) GRB radiative processes;
the HERMES project. The HERMES concept is
based on relatively small but innovative X-ray d) the granular structure of space-time.
detectors (collecting area in the band between
a few keV to a few hundred keV of 50-100 cm2), The Swiss Federal Institute of Technology,
hosted by 3U CubeSats (10x10x30 cm, weight Lausanne, Switzerland (EPFL) together with
5-6 kg), launched in equatorial Low Earth Orbit the Paul Scherrer Institute in Switzerland (PSI),
(LEO). The transient position is obtained by presented a joint mission concept called
studying the delay during the arrival times of CHESS (Constellation of High Energy Swiss
the signal upon different detectors, placed Satellites), a student mission whose goal is to
hundreds/thousands of km away. This large launch a constellation of 4 CubeSats for high-
increase of the discovery space on the physics/ energy astrophysics studies in late 2021. It
10 太空|TAIKONGFigure 5: The CHESS 3U CubeSat constellation - Credits: CHESS mission
intends to bring together Swiss universities into of this writing and presented here, may have
a collaborative national project for scientific changed].
research. The four identical nanosatellites will
embed a Hard X-Ray polarimeter developed Some science driven projects were presented
at PSI, which is a novel, miniaturized detection also by the College of Astronautics,
system developed for precise observations of Northwestern Polytechnical University, China,
the solar system, the Sun, and even fundamental where CubeSats are used as a new platform for
astrophysical processes occurring in distant Deep Space Research, like “Deep space and
galaxies. It will enable the simultaneous study asteroid research” and “Beyond Atlas project
of gamma-ray bursts and solar flares, including for Asteroid”, a low-cost deep space project
Space weather phenomena. that will use a 12U CubeSat to research the
asteroid 2016HO3. Mendorn AB will initiate it
With a carefully-synchronized timing between in collaboration with Ericsson, OHB Sweden,
the CHESS CubeSats, it will be able to KTH, etc. and a “Deep Space Observation
determine the direction of the detected mission”, which will use several CubeSats
Gamma-Ray Bursts and correlate the event with and femosatellites for an asteroid mission.
potential Gravitational Waves measurements This mission constitutes one of the piggyback
[please note that since the project is work in payloads of Chinese asteroid mission.
progress, some aspects of it, valid at the time
太空|TAIKONG 112.1.3. Engineering-driven presentations
Several participants focused the topic of satellite to reduce its orbital energy and
their researches on the engineering behind eventually insert into synodic resonant libration
CubeSats. point orbits near the second Lagrangian point
of the Earth-Moon system. From this privileged
Some recent activities at ISAS/JAXA, Japan, outpost, the spacecraft will study the lunar
involving deep-space exploration with flash impacts that occur on the far side of
CubeSats and/or small satellite platforms the Moon and help characterize the size and
were expounded. Specifically, the mission distribution of Near-Earth Asteroids with data
requirements and trajectory design of two 6U and statistics impossible to make with ground-
Japanese CubeSat missions that will fly as a based telescopes. EQUULEUS will also study
piggyback project of NASA’ Space Launch the cislunar dust environment and test key
System during its maiden mission Artemis-1 technology for future deep-space CubeSat
were reviewed. The two CubeSats are named missions, like a water resisto-jet propulsion
EQUULEUS and OMOTENASHI and they system capable of delivering up to 80 m/s of
differ greatly in terms of mission life span Delta V.
and objectives. OMOTENASHI is equipped
with a solid rocket motor to decelerate its The Mahidol University of Thailand introduced
relative velocity with respect to the Moon and a space exploration payload for a CubeSat.
carry out the first lunar semi-hard landing (by The payload aims to detect the high-energy
requirement, the touchdown speed shall be particles in space, cosmic ray, which will enable
less than 100 m/s). Key technologies are being us to understand the behavior and origin of the
developed and will be proven to enable cheap particles. However, the key challenges include
and fast access to the surface of the Moon. the development of a payload to observe the
particles, their direction and energy. The main
EQUULEUS is another technology mission is a 3U CubeSat at an altitude of 600
demonstrator that will fly by with the natural km in a polar orbit with an energy detector
Figure 6: The EQUULEUS satellite - Picture Figure 7: External view of the deployed
Credits: JAXA EQUULEUS nanosatellite - Picture Credits: ISSL, JAXA
12 太空|TAIKONGoptimized between the 2-200 MeV energy the Academic Challenge of Knowledge
range. Hence, the space exploration mission is SATellite activities in Thailand. The first
the technological demonstration of Cosmic-ray entirely built in Thailand 1U CubeSat is called
electron/positron detection in space. KNACKSAT, developed in the context of
Figure 8: The KNACKSAT satellite
Also, more engineering work was put forward the educational space technology program
by CONIDA, Peru, i.e., the microstrip antenna of Thailand. The university team of five staff
showing two models with circular polarization members and 25 students launched the 1U
in the S & C band to be applied to the 3U CubeSat via the Spaceflight’s SSO-A (Sun
CubeSat, including the technology of the UHF Synch Express) mission in September 2018.
and VHF transceiver board an S-band down- The students’ activities and process learning
converter kit for Ground Satellite stations included satellite design review, space
as well as the installation and maintenance environment testing, satellite integration,
of satellite receiving stations L, X band for ground station, and the signal elaboration
weather forecast satellites AQUA, TERRA, received from the satellite, among others. Two
METOP, NOAA. other peculiar goals of this CubeSat were the
Amateur Radio Linear Transponder as well as
The GISTDA, Department of Electrical space pictures.
Engineering, Prince of Songkla University,
Thailand, presented the first 1U CubeSat Another example of a CubeSats' based
developed by King Mongkut's University of project is to be found in the Institute of Space
Technology North Bangkok (KMUTNB) within Technology, Islamabad, Pakistan, as it brought
太空|TAIKONG 13Figure 9: (Left) The Mongolian engineers who developed “Mazaalai satellite”, a 1-unit CubeSat launched on June 3,
2017, as part of the SpaceX CRS-11 mission.
Figure 10: (Right) Its deployment from the ISS. This satellite was sent to ISS through the SpaceX CRS-11 mission and
launched in a Dragon spacecraft on the Falcon 9 rocket from NASA Kennedy Space Center. The satellite was in orbit
around the Earth at an altitude of approximately 400 km and at an inclination of around 51 degrees, completing an orbit
every 92. Unfortunately, Mazaalai was deorbited on May 12, 2019.
forward the CubeSats engineers’ works related For what concerns the Mazaalai satellite,
to the design of the Magnetometer Unit for a Figure 9 shows the Mongolian engineers who
university Microsatellite and a design of Power developed i, while Figure 10 shows the its
subsystem for 3U CubeSat. deployment from the ISS. This satellite was sent
to ISS through the SpaceX CRS-11 mission and
The Mongolian space technology history was launched in a Dragon spacecraft on the Falcon
also one of the topics of the forum, including 9 rocket from NASA Kennedy Space Center.
the BIRDS interdisciplinary satellite project, the Mazaalai is a 1-unit CubeSat launched on June
Mongolian team participation in these projects, 3, 2017, as part of the SpaceX CRS-11 mission.
and Mazaalai, the first Mongolian satellite. The satellite was in orbit around the Earth at
an altitude of approximately 400 km and at an
The BIRDS project is a multinational joint inclination of around 51 degrees, completing
satellite plan for non-space faring countries an orbit every 92. Unfortunately, Mazaalai was
supported by Japan and joined by four deorbited on May 12, 2019.
countries, i.e. Ghana, Mongolia, Nigeria,
and Bangladesh. Under this project, three The Department of Astronautical Engineering,
Mongolian students have participated in the University of Turkish Aeronautical Association,
design, development, and operation of the Turkey) put forward the five in-orbit CubeSats
country’s first-ever satellite. The BIRDS project’s of Turkey. Two of these CubeSats are included
fourth phase is ongoing. in the QB50 project and involve science
14 太空|TAIKONGpayloads of multi-needle Langmuir probe in for CubeSat applications, it is easy to envision
addition to an X-ray detector in one of the a CubeSat mission devoted to the study of
satellites. Furthermore, the science mission gravitomagnetic effects, such as the frame-
Figure 11: QB50 Project - Credits: www.qb50.eu
plans of the University of Turkish Aeronautical dragging effect due to Earth’s rotation. This
Association (UTAA) using CubeSats were effect creates a difference in the signal rotating
discussed. The main science focus at UTAA is in the direction of Earth’s rotation and in the
placed on gravitational physics and in accord opposite one. A mission concept proposal
with this target, the mission ideas concern can be the one described in Ruggiero and
general relativity, especially gravitomagnetism. Tartaglia, 2009, where three satellites in GEO
orbits creates electromagnetic signals rotating
Following a formal analogy between around Earth in opposite directions and time
electromagnetism and linearized Einstein’s the rotation of these signals [12].
gravity, gravitomagnetism represents the
kinetic effect of gravity just like the magnetic
effects for a moving electric charge. The tests of
gravitomagnetism were carried out with some
past satellite missions such as LAGEOS and
Gravity Probe B. Nevertheless, there is always
a definite need for tests of gravitomagnetism
with improved accuracy. With the advancement
of chip scale atomic clocks, which are suitable
太空|TAIKONG 152.1.4. Education-driven presentations
Miniaturization of modern electronics and disruption and gives a valuable insight to the
sensor technology has induced large-scale countries and teams who find themselves on
democratization of space access, as satellites a similar path. The presentation showed the
can be built and launched with only a fraction efficacy of well-channeled education to create
of the former multimillion costs. This disruption economic activity and boost science outcomes.
has brought new opportunities to smaller and
developing countries around the world to build The Foresail-1 CubeSat designed in Aalto
national capacities to advance and run their own University, Finland, carries interesting science
space assets. Affordable satellites bring also payloads and technology demonstrators to
viability to large scale commercial constellation deorbit the spacecraft. The mission objective
projects and bring new opportunities for is to measure radiation belt losses using
education and science. particle telescope, demonstrate coulomb
drag propulsion (CDP) for deorbiting, test an
During the Forum, the “Foresail satellites for ultra-sensitive magnetometer, and prepare
space science by Finnish Centre of Excellence for high radiation missions. The Particle
in Sustainable Space” was presented as a Telescope payload has the requirement to
beautiful example of the development path orient its detector with shorter collimator
from the first student-built spacecraft to the towards the Sun, while the detector with longer
booming New Space economy and national collimator serves to scan the environment.
science satellite programs in Finland. The The CDP requires spin control for deploying
development took less than ten years and and maintaining the tension of the tether to
thus, the Finnish example exemplifies the most demonstrate the deorbiting.
important benefits of current space technology
Figure 12: Foresail-1 is a satellite mission of the Finnish Centre of Excellence for Sustainable Space, and its main
payload is the Particle Telescope (PATE), developed by the University of Turku – Picture Credits: Aalto University, Finland
16 太空|TAIKONGAnother analysis of the educational advantages University and Jordi Puig-Suari of California
of CubeSats was explored by the Technical Polytechnic University [15], have evolved to
University of Munich, Germany, as three main become accepted platforms for scientific
points were put forward: and commercial applications. This trend has
accelerated, and a 2016 report from the Space
• Architectural and Engineering - Overview Studies Board of the US National Academies
of University-built CubeSats; of Sciences (NAS) found that over 80% of all
science focused CubeSats were launched
• CubeSat deep space exploration - between 2010 and 2016 and more than 80%
targets and missions; of peer-reviewed papers reporting science on
CubeSats were produced from 2010 on [11].
• CubeSat deep space exploration - This acceleration is fueled by the miniaturization
design considerations. and increased utilization of commercial off-
the-shelf (COTS) parts and led to a more or
While the second and third presentations less Moore’s Law equivalent growth of ground
focused on deep space exploration with sampling distance (GSD), data rate, and data
CubeSats — a goal pursued by more volume of small satellites between 1990 and
experienced teams and/or national space 2010 [11].
organizations — the first talk described the
main lessons learned during 13 years of Over the past 13 years, three CubeSats were
CubeSat development at TUM. successfully developed and launched at
TUM. The endeavor started in 2006 with the
CubeSats, once invented for educational development of First-MOVE (see Figure 13
purposes in 1999 by Bob Twiggs of Stanford on the left). The main goal of First-MOVE, as
Figure 13: First-MOVE (left) and MOVE-II (right), both 1U-CubeSats from LRT
太空|TAIKONG 17in many CubeSat programs of that time, was by the Bearden rule: Complexity in missions
the hands-on education of undergraduate increases cost and development time, with a
and graduate students and the ambitious linear relationship for schedule and exponential
design and build of a 1U CubeSat verification for costs. If we demand too much complexity
platform [2][4]. The First-MOVE was operated out of a limited budget and schedule, it will
successfully during one month after its launch in lead to failures. This is especially worthwhile
late 2013. Until then, more than 70 students of to consider for interplanetary missions, as the
different faculties had participated successfully launch opportunities are rare and thus the
in the project, with numerous educational and demand for more experiments on one specific
programmatic lessons learned [5]. Starting mission are usually high. Looking at the results
in April 2015, the second CubeSat of TUM, found by the Aerospace Company for SmallSat
called MOVE-II (see Figure 13 on the right) missions [1], a zone with impaired and failed
was developed and launched into space in late missions, thus an area in which complexity is
2018 [7]. too high with respect to schedule and cost can
be seen in Figure 14.
Besides hands-on education, a scientific
experiment dedicated to novel solar cells is The last couple of years showed that CubeSats
flown on this satellite mission [13]. CubeSats, are a feasible tool for conducting scientific
in discrepancy with their bigger counterparts, experiments, both in the Earth orbit but also in
can be built, tested, and launched very fast. A the interplanetary space. The upcoming launch
clone of MOVE-II, called MOVE-IIb was build of Artemis 1 will deploy 13 CubeSats [8] with
and tested within six months, and launched a broad variety of planned experiments into
into space in July 2019, within a year from the interplanetary trajectories and many future
start of the project. deep space launches will have reserved volume
for scientific CubeSats. Independently from the
The most important lesson learned regarding mission, CubeSat developers should also keep
university-built CubeSats (and also commercial the Bearden rule in mind when planning their
missions) is the relation between complexity scientific missions.
and cost/schedule. As stated by McCurdy [9],
the aggregation of failures can be by explained
Figure 14: Successful, failed and impaired SmallSat missions analyzed by the Aerospace Company. Source: [1]
18 太空|TAIKONGFigure 15: The DUT-1 Satellite developed by Dalian University of Technology, Changguang Satellite Technology Co. Ltd., Tsinghua University, Wuhan University, and Xinjiang Institute of Physics and Chemistry - Credits: DUT As an example of CubeSats-based endeavors • the importance of good and exhaustive that also function as a students’ educating documentation, which is often a quite tool, the DUT-1 (Small Bright Eye) mission is the difficult task for students; result of the joint efforts of Dalian University of Technology, Changguang Satellite Technology • the relevance of interdisciplinarity as co. ltd., Tsinghua University, Wuhan University, students are typically focused on their and Xinjiang Institute of Physics and Chemistry specific field and often neglect other with the participation of more than 100 students less known effects during the design of in the development. DUT-1 is the first 20 kg CubeSats; sub-meter high-resolution remote sensing 12U CubeSat and it includes three main payloads, • the significance of environmental i.e. a high-resolution camera (PAN/Multispectral conditions in the selection of parts; low-cost and high-resolution camera), electric propulsion (μCAT micro-electric propulsion • the lack of appropriate redundancy or, system), and a space radiometer to monitor the even worse, the use of redundancy in an real-time dose rate in space. By means of state- appropriate way; of-the art, innovative technology — 3D printing structure, 3D printing launch pod, integrated • the unavailability of parameters of ADCS, and reflect-array antenna — and quality several components (e.g. rechargeable features, such as a pointing accuracy of
In practice, from the education point of • improvement of the primary structure of
view, much was learned rather during the CubeSats by using the empty volume
design phase than during the launch and on lateral surfaces between lateral rods,
operationSome of the lessons include: increasing structural robustness, getting
rid of useless items, and improving heat
• interdisciplinary team set-up; transfer;
• ability to build a complex system; • taking advantage of modern model-
based design in the development of
• huge amount of knowledge and subsystems to decrease the complexity
capabilities taught to students; of student tasks to make them accessible
to master students and to improve the
• students faced with the complexities of quality of the documentation as well as
practical tasks. testing and qualifications;
Since design, manufacturing, test, • the embedding of most spacecraft
documentation account for 90% of the efforts functions inside the lateral surfaces of a
and benefits with only 10% of the costs, while CubeSat and make them also structural
launch and operations account for 10% of and thermal elements;
the efforts and benefits with 90% of the costs
(mostly for the sat-launch), some questions the • the improvement of the heat transfer of
necessity of launching for teaching. mechanical interconnections between
removable structural elements;
Moreover, students should face a degree of
complexity which is compatible with their • the embedding of electromechanical
knowledge; therefore, they should be assigned subsystems (e.g. magnetorquers,
with sub-subsystems only. It is utterly important reaction wheels, batteries) inside the
for students to understand well the mission lateral skins of the spacecraft, making
and its requirements in order to develop the them thin enough;
subsystem handed to them, while system-level
tasks should belong to permanent staff’s duties • the description the operation and
(teachers or PhD). optimization of on-board telescopes
(tutorial);
Further details discussed in the presentation
concerning the Politecnico di Torino include: • the concepts of attitude and optics
required to understand the principles of
• the current activities on the development operation of a telescope, both reflective
of “smart structures” promoted by the and refractive;
university;
20 太空|TAIKONG• the performance parameters of a • the optimization of geometrical
telescope (e.g. field of view, resolution); parameters to improve telescope
parameters given some mission-
• the formulas to compute focal length dependent constraints;
of telescopes and the relationships with
telescope parameters; • the introduction of a panel on
technological capabilities of modern and
• the physical phenomena leading to future CubeSats with a short introduction
image aberrations;
of state-of-the-art technologies.
3. MAIN TAKEAWAYS ON CUBESATS
TECHNOLOGY AND CUBESATS-BASED MISSIONS
The great efficiency resulting from high level based on CubeSats constellation missions.
productivity at lower costs and lower energy- Specifically, scientists were able to acquire
usage ensured by CubeSats (‘or small more knowledge on the following aspects:
satellites’) technology is deemed to outperform
traditional satellites in these primary aspects. 1. CubeSats highlights: Efficiency,
As a matter of facts, even though CubeSats constellation missions, deep-space
were first developed at university level for exploration:
educational purposes, they do now represent
an advantageous solution also for commercial CubeSats are a convenient, light-weight,
missions led by space agencies as well as for joint sustainable solution for space science missions
projects across countries. For these reasons, as their production and launching costs are
the forum aimed to provide all participants significantly lower than in traditional satellites.
with the opportunity to learn more about Their reduced dimensions come with several
CubeSats’ architecture, their development, benefits not only in terms of reduced costs, but
structure and characteristics, their launching also in terms of risks and reachability. In fact,
and deployment techniques, design criteria, while large satellites can only cover a relatively
space engineering, as well as the current status limited portion of space, a constellation of
of several countries’ advanced studies and CubeSats can work on a larger area at the same
missions based on Cubesats. time, thus expanding the potential of space
missions.
Furthermore, researchers and engineers were
also given the chance to inquire about potential While Earth-bound satellites remain vital for
collaboration opportunities at international educational and scientific activities, CubeSats
太空|TAIKONG 21interplanetary trajectories and many future
deep space launches will have reserved volume
for scientific CubeSats. Even with a small
10x10x10 cm3 CubeSat and with 3U CubeSat
it is possible to carry out important missions
involving inter-sat communication, remote
sensing, Bio Science missions. Solar sail used
in CubeSat to deorbit it was also an interesting
mission.
2. CubeSats beyond universities:
CubeSat is still used for what it was first created
for, i.e. education at universities and they are
indeed a great tool for education, while for
some countries they also often represent the
very first launched satellite at country level (e.g.
Switzerland's first CubeSats launch in 2009).
Nevertheless, this rapidly developing field of
CubeSat offers new opportunities for numerous
space research areas. Using miniaturized, low-
power instrumentation developed for cube-
satellites it is possible to reduce time from
the mission concept to real measurements in
Figure 16: ARTEMIS-1 Satellite - Picture
space. CubeSat is also a cost-effective mean to
Credits: NASA
get a payload into space to perform research
and develop new technologies.
and small satellites in general still represent an
invaluable asset for deep-space exploration 3. Technical knowledge:
(even though some questions remain on their
feasibility for interplanetary missions). In terms of technical knowledge and takeways,
they can be summarized in the following points:
The last couple of years showed that CubeSats
are a feasible tool for conducting scientific • Hardware and Software Reliability:
experiments, both in Earth orbit but also in Design and Testing
interplanetary space. The upcoming launch
• Software Reliability
of Artemis 1 will deploy 13 CubeSats [11] with
a broad variety of planned experiments into
22 太空|TAIKONG• Modular approach and it’s benefits • Engineering Overview of Foresail
CubeSats
• Compact design subsystem
• Aoxiang series CubeSats, development
• COTS, Rad Hardening and Reliability and trends
relation
• Aalto University and its vision of a
• State of Art Sensors used on CubeSat “Finnish Centre of Excellence in
Sustainable Space”
• Statistical trends of CubeSat
• General application of the sequence:
• Know-how development CubeSat Development by integration
of tested modules – Development by
4. Fostering know-how development and integration of tested modules and
sharing is a key strategy to improve skills design/implementation of subsystem
and capabilities, and in this regard, the – Development by full custom design
following aspects where considered:
• Management of Development Team
• MOVE I Mission: Overall design and the challenge of knowledge
considerations. management when working with
students
• Choice of Communications Bands
(IARU/UIT) • Korean SNIPE, use of IRIDIUM
as backup Communication
• Italy’s experience on teaching university and formation flight strategy
students how to use CubeSats: It’s
worth it even if not launched
Figure 17: The South Korean SNIPE Satellite –
Credits: KASI
太空|TAIKONG 235. The importance of interdisciplinary costs and development time, with a linear
research on CubeSats: relationship in terms of schedule, while it is
exponential for costs. Such relationship is
The combination of physics, relativity, a particularly significant for interplanetary
and astronomy together with engineering missions, as the launch opportunities are rare
knowledge is a win-win interdisciplinary and thus the demand for more experiments on
approach. Physics-based presentations one specific mission are usually high.
were particularly useful to understand the
challenges associated with operating more 7. CubeSats’ main challenges:
than one satellite at a time as well as with
finding optimal trajectories that would fulfill Among the main challenges faced by
the mission objectives. Nevertheless, it was developers, researchers and engineers
clear that, without access to small satellite of CubeSats we enumerate the lack of
technologies, high-energy or general relativity- standardization in terms of interface, which
based missions would be overly costly and may complicate the collaboration among
unfeasible. Scientists, especially those who different actors. Furthermore, the space debris
deal with abstract topics such as relativity problem was also suggested, a nowadays small
and astronomy, are more deeply involved in but still rapidly growing problem. Even though
CubeSat missions than expected by common CubeSats are not the main concern in this
sense. Furthermore, also theoretical physicists regard — only 800+ of them launched up to
have expressed deep interest in the CubeSat now — a solution still needs to be found, and
business, and in a similar token, participants EPFL is working on it through CleanSpace One.
expressed an enhanced interest in missions Another topic was the need for improvement
which do not prioritize technology but rather in CubeSat structure. Finally, even though the
science questions, such as the Korean SNIPE interface standardization is a change needed
mission. In fact, even though this mission does to simplify CubeSats-based collaboration,
not have revolutionary and state-of-the-art the standardization of the CubeSat deployer
technologies, it puts emphasis on ionospheric reduced the flexibility left to developers to
and magnetospheric science questions, as adjust the shape and volume of a CubeSat.
it was also the case of some other missions
driven by science questions. 8. Insights from operating missions (Hermes,
CHESS, etc.):
6. Complexity–costs relation:
The HERMES and CHESS mission discussions
One of the most important lesson learned of provided insights on an inspiring science
university-built CubeSats (and also commercial application of CubeSat platforms. Both
missions) is the relation between complexity missions aim to study the electromagnetic
and cost/schedule. As stated in the previous counterparts of the gravitational waves, paving
section, missions’ complexity increases both the way to multi-messenger astronomy. The
24 太空|TAIKONGFigure 18: Cleanone Space satellite - Credits: EPFL
talks of “COSPAR Roadmap on 4S” and presentation on the “CubeSat Technology (in)
“Using CubeSats for Science Missions seen capabilities” brought forward the lessons learnt
from a physics point of view. What can we do for university-level CubeSat developments.
and when?” gave a general perspective on
the future science missions with CubeSats. In 9. Cross-country collaboration
particular, the swarm explorations of a solar
system body and the vision for a visit to Alpha As outlined in the last section of this magazine
Centauri with very tiny chip size satellites (‘International collaboration'), despite
are promising perspectives on solar system the evident financial benefits guaranteed
explorations and interstellar visits. by CubeSats, the development and
implementation of space science missions can
In addition to these visionary discussions, the still represent a tedious challenge in terms of
presentations on the ongoing CubeSat science financial, technical and technological resources
mission developments offered insights on for many countries. Less developed countries
the current capabilities of doing science with nowadays have the capability to launch their
CubeSats. These missions are the Japanese own scientific CubeSat, but they may face some
Moon exploration missions with CubeSats, difficulties in terms of funding and governments’
which are EQUULEUS and OMOTENASHI, the willingness to support the projects. Moreover,
Korean CubeSat constellation mission for small the cooperation between teams under the
scale magnetospheric and ionospheric plasma form of exchange of students and staff would
studies, that is SNIPE, and the FORESAIL help differentiate the experience among teams
missions of Finland for studying space and improve future missions.
environment at LEO and GTO. Furthermore, the
太空|TAIKONG 2510. Overall knowledge on many topics Model, Wideband Model, Two satellite Model,
acquired: Mobile-Satellite Channel Model, Radiometry
missions, Atmospheric Radiometry, Deep
Applied Plasma Physics, Electric Propulsion, Space Missions, Design optimization of
Experimentation, Design, and Development CubeSat telescopes and imagers for Earth and
Process. Also, come to know some Experimental space observation, Classification of satellites,
Study of Effects of Electric and Magnetic Field future tend of CubeSats technology, High
on Plasma, Propulsion System about satellite, Gain Microstrip Antenna Design for CubeSats,
cold gas, liquid, resistors, rf ion, electrospray, COSPAR Roadmap on Small Satellites for
pulse plasma, and vacuum arc thrusters, Space Science(4S) Engineering overview
rain fade prediction software, some models of Foresail satellites, PharmaSat, GraviSat,
affiliated with Megacells such as Loo Model, SporeSat, EcASat and BioSental, Small scale
Statistical Model, Corazza Model, Lutz Two state Magnetospheric and Ionospheric Plasma
Channel Model, Physical-Statistical Models, Experiment(SNIPE) Solid State Telescope,
Time Share of Shadowing Models, Time Series Magnetometer, several Ground Stations.
4. RECOMMENDATIONS FOR NEWCOMERS IN
CUBESAT MISSIONS
4.1. CubeSats for interdisciplinary, multi-layered collaboration
CubeSats provide the largest single standard CubeSats also constitute a very affordable
launch market available at the moment, creating platform for hands-on learning of space
a rapidly developing ecosystem around it. technology and it has so far shown a strong
They ensure easy access to a wide range of capability to incubate new business ideas. It is
innovative ideas to any country that enters the also an affordable instrument for developing
field, as CubeSats do not simply represent a space science and scientific missions and rise
standard spacecraft but rather a collaboration, overall awareness in global technology topics.
innovation, and education platform. A single
CubeSat launch is not necessarily a big Moreover, they can be developed fast and
breakthrough in space technology, but it cheap. As such, CubeSats make space research
prompts the community and young teams accessible for universities all around the world
around to build the national capacity to launch and put space research in high gear, leading
and operate national space missions. to amazing possibilities. Perhaps future
26 太空|TAIKONGplanetary missions could also include one or to be successful, the CubeSat developments
two student-led CubeSats that would operate should always involve a novel element in
independently of the main spacecraft, limiting order to start partnerships with other industry
the cost impacts to the primary mission. It is players. A CubeSat is legislatively equal to a
undeniable that the possibility to build one’s large spacecraft and therefore a single national
own spacecraft to make measurements on Mars CubeSat can lead to significant developments
or on a comet or anywhere else in the solar in the national legislation as well as in the
system could energize the next generation organization of space activities at higher level.
of planetary scientists and engineers. These
scientists and engineers can get involved in Last but not least, they are a very good option
the entire life cycle of the satellite, thereby for engineers to work in collaboration with
facilitating and maximizing technology transfer. other engineering departments. A CubeSat-
based project can involve electronics,
Moreover, countries that are setting foot in communication, mechanics, aerospace, and
the CubeSat industry should consider the system engineers, who can all commit to the
community aspect and enable their young mission to polish their skills and gear up for big
CubeSat teams to visit conferences and satellites and big projects.
workshops to develop connections. In order
4.2. Key lessons for newcomers in the CubeSats industry
Newcomers in the CubeSat missions have projects. While building and operating a
the opportunity to work on a wide range of satellite in space remains a key activity
missions. Nowadays researchers are running for educational and social purposes, it
numerous important projects by means of is true that some interesting scientific
CubeSats technology, including remote experiments could be made “along the
sensing, communication, Earth-imaging, space way” while developing the necessary
exploration, inter-sat communication, air traffic protocols and know-how to design and
management, ship tracking, and there are operate a CubeSat. A clear scientific
many other missions which could be carried purpose would widen the impact of their
out by means of CubeSat technology corresponding spacecraft project as well
as attract the interest of the international
Therefore, newcomers in CubeSat missions are community;
encouraged:
• to focus on intersystem tests, i.e. a test
• to focus on and be creative with the program that should evolve around
scientific motivations beyond their sub-system interactions. A rudimentary
太空|TAIKONG 27standard function test of each sub- and the process of learning about a
system is naturally mandatory before CubeSat mission. It is necessary to learn
system integration, but letting the from commercial CubeSats and focus
systems perform with each other will only on the payload design to make
assure full functionality and at the the first mission a success. One should
same time give sub-system developers learn the whole process that leads to the
a deeper understanding of their own CubeSat launch to acquire know-how;
system. Although the space environment
is different from a lab setting and it is • to note that redundancy is the key for a
hostile to satellites, the major reasons successful CubeSat mission. However,
for CubeSat failures built by new-comers one needs to be careful about the trade-
are inter-system failures; off between complexity and redundancy,
as every redundancy introduced makes
• to keep the Bearden rule in mind the system more fault-tolerant, and at
when planning a mission. This does the same time it makes it more complex
not necessarily imply the reduction or to manage the system;
resizing of the scientific outputs and
goals of the mission, it rather means to • to have real science objectives and
reduce the complexity of experiments to produce real data. Nowadays, it
and of the satellite itself. This can be is getting harder and harder to get
deeply enhanced by the already available funded for an education-only CubeSat
subsystems or products on the market, mission. Indeed, one cannot forget that
also coming from terrestrial applications, a CubeSat mission is not only about
which can be reused in CubeSat building a CubeSat and launching it, but
missions. At the end of the day, CubeSats also about getting data and analyzing
have to be fast-to-build and relatively them. Nevertheless, for a newcomer
cheap – but both characteristics can be who has no prior experience with
aligned with the scientific objectives of CubeSats and space missions in general
the mission, as proven by the successful and who cannot resort to the help of
Lunar Prospector and Mars Pathfinder experienced people, it might be better
(and Sojourner) missions of the Faster- to focus on a small 1U mission or to
Better-Cheaper program; gather experience in other ways. Also, it
comes without saying that if a CubeSat
• to lay out the concrete mission goals is built by students, the likelihood to
before actually building the CubeSat. It is have numerous mistakes is much higher
nowadays easier to enter the field since than with a full-time team. Therefore,
one can learn from the lessons that other being vigilant and debugging frequently
missions have provided. However, the are two must-do. For what regards a
critical issue is the project management university’s concerns, the most important
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