COSPAR Issues Heliophysics Guidelines

Recognizing that all of humanity lives on the same planet, under the same star, the Sun, and
underscoring the importance of cooperation and the open sharing of scientific results and data for
Heliophysics research;
Noting that a new scientific discipline, “Heliophysics”, has evolved to meet the challenges posed by
our technological society living with a volatile star, and has unified the distinct scientific disciplines
of solar physics, space plasma physics, and aeronomy under a common umbrella of scientific
inquiry;

Ushering in a new era of Heliophysics research that leverages advancements in space accessibility,
commercial capabilities, artificial intelligence/machine learning (AI/ML), and that addresses societal
needs of an advancing technological society;

Building upon almost 70 years of space-based Heliophysics research, that began with the launch of
humanity’s first satellites, that discovered Earth was surrounded by radiation belts;
Considering that the science of Heliophysics is cross-disciplinary and involves the study of
complex systems-of-systems, and requires multipoint, heterogenous constellations of space- and
ground-based measurements, and advanced numerical simulations, all built upon open data, open
science, and unified data standards;
Acknowledging that the influences of the Sun through Space Weather impacts all of humanity,
both at home on Earth and during humanity’s journey of exploration through the Solar System,
including the continuous human presence in low-Earth orbit, and expanding to the Moon, Mars,
and throughout the Solar System;

Affirming that Heliophysics has always been an international endeavor, with examples going back
to the International Geophysical Year (IGY), extending through the International Solar Terrestrial
Physics (ISTP) Program which was endorsed by the Inter-Agency Consultative Group (IACG), and
exemplified most recently by the International Living With a Star (ILWS) program and the newly
created WMO-COSPAR-SES working group, defined by the Coimbra Declaration, formed to
improve the global coordination of space weather activities;
Further affirming the value of international scientific collaboration that forges bonds between
nations and opens dialogue between peoples;
Desiring to establish a common worldwide Heliophysics discipline, centered on the study of the
Sun and its interaction with Earth and other solar system bodies, with coordination of ground- and
space-based assets, and universal community best practices including open data, open science, and
unified data standards;
Therefore, COSPAR maintains and promulgates these Guidelines on Heliophysics:

Section 1 – Purpose

The purpose of these Guidelines is to promote a common vision for the new scientific domain of
Heliophysics, the study of the Sun and its effects through the solar system, via a practical set of
non-legally binding guidelines and best practices to enhance and enable scientific discovery while
also advancing understanding of variability in space (Space Weather), the applied aspect of
Heliophysics, to guide system design and mitigate its impacts.
Scientific studies of the Sun and its interactions with Earth and Solar System bodies predate the
space age. With the launch of Sputnik 2 and Explorer I, which both discovered the radiation belts,
humanity began to explore space with in situ and remote instrumentation and at electromagnetic
wavelengths otherwise shielded by Earth’s protective atmosphere. Over the ensuing decades,
humanity has explored the furthest reaches of the Solar System, established a continual human
presence in space, and has come to rely on space for critical elements of our society. Heliophysics
has expanded into the study of both fundamental plasma physics in the natural plasma laboratory of
humanity’s cosmic backyard and the space weather that impacts society. Heliophysics research and
model development underpins the protection of vital technological infrastructure and humanity’s
journey into space.
Humanity’s ever-increasing understanding of the Sun-Heliosphere system led to the unification of
solar physics, space physics, and aeronomy, into a new scientific domain called Heliophysics.
Heliophysics, the study of the Sun and its effects throughout the Solar System, is a recognition of
the cross-disciplinary nature of the subject, and the inherent need to bring disparate skillsets together
under a common theme. Space plasma physics, the science of how ionized and partially ionized
plasmas behave in the presence of electromagnetic fields, is the foundational scientific discipline that
undergirds the field.
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Notably, the core disciplines of Heliophysics connect strongly with Astrophysics, Planetary science,
and Earth science:

• Solar physics synergizes with astrospheres and exoplanet systems, solar-stellar comparisons, eruptive events on other stars, and laboratory astrophysics;
• Heliospheric physics investigates the life cycle of the solar plasmas and magnetic fields, and interplanetary dust that permeate the solar system, and their interface with interstellar space;
• Magnetospheric physics synergizes with star-exoplanet interactions, the comparative physics of driving by solar outflows on solar system bodies;
• Aeronomy and ionosphere-thermosphere-mesosphere (ITM) physics studies the interface of planetary atmospheres (Earth and Planetary science) with space;
• Finally, space plasma physics synergizes with lab plasmas and fusion devices and leverages our local cosmic plasma laboratory for fundamental plasma physics studies.
• Space Weather, the applied science of Heliophysics, addresses the impact of the dynamic nature of the Sun on humans, society, exploration, technologies, and critical infrastructure in space and on
• surfaces of solar system bodies.

Humanity has extended from the physical domain of our birthplace, Earth, to the neighboring
domain of the Heliosphere, carved out by the ever-flowing solar wind. Space-based infrastructure
has grown explosively in the past half-century, such that space is increasingly crowded, and subject
to highly variable space weather impacts. Furthermore, humans have been living continuously in
space for the past three decades, and plan a sustained presence throughout the Heliosphere,
including on the Moon and at Mars. Now that humanity has moved from Earth into the physical
domain of the Heliosphere, the requirements on its study have changed to the point that we need to
understand the inherent connectivity of the systems. In this sense, Heliophysics is truly a new
science domain, unifying a wide array of scientific disciplines and expertise under a common science
theme. Humanity is no longer simply observing some remote cosmic realm; a new level of
understanding is required to develop and inhabit this harsh new environment. Such a large effort
calls for a coordinated scientific discipline and scientific program, if humanity is to continue to
progress from the domain of our birth, Earth, to the domain of the stars.
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To fully realize the potential of Heliophysics as a driving force for scientific discovery and societal
benefit, a clear understanding of its fundamental principles is essential. These principles are outlined
below:

1. In the same way that astrophysics is the science of the domain of the stars, Heliophysics is the
   science of the domain of the Sun.
2. The domain of the Sun includes the Heliosphere and all solar system objects, including the Sun
   and Earth.
3. Within this domain, Heliophysics is a science of connections of systems-of-systems, including
   the Sun and extended solar atmosphere, planetary ionosphere-thermosphere-mesosphere
   systems, planetary magnetospheres, and the interplanetary space that connects these systems.
4. Heliophysics requires inherently multi-disciplinary skill sets and includes components of solar
   and space physics, aeronomy, ionosphere-thermosphere-mesosphere (ITM) physics,
   magnetospheric physics, and planetary physics, among others.
5. The disciplines that comprise Heliophysics often sit at the boundaries of Earth Science, through
   atmospheres and ionospheres, Planetary Science, with magnetospheres and exospheres, and
   Astrophysics, including stellar activity and exo-planetary habitability. These boundaries are not
   sharply defined, but point to the cross-disciplinary nature of Heliophysics. Heliophysics also
   links to Biological Science via space weather impact on humans.
6. The physics of ionized and partially ionized plasmas, including dusty plasmas, is common across
   these components.
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   Section 2 – Definitions
   “Heliophysics” is defined as the study of the Sun and its effects throughout the Solar
   System;
   and
   “Space Weather” is defined as applied research on the dynamic, highly variable
   conditions of the space environment, including the Sun, its effects on society and its
   extensions within the Solar System, and on human biology.
   Section 3 – Open Heliophysics
7. These Guidelines encourage open sharing, widespread dissemination, sustained archiving, and
   discoverability of Heliophysics-related scientific data, making the observational data and
   scientific results obtained available to the public and the international scientific community, as
   appropriate, in a timely manner. These include, but are not limited to, near real-time data, data
   from ground-based instrumentation such as telescopes and radio arrays, magnetometers and
   ionospheric radars, riometers, and all-sky imagers, and in-situ and remote space-based data
   measurements.
8. These Guidelines endeavor to expand access to open data, Heliophysics datasets should be
   archived for current and future generations, and ideally contain sufficient documentation to
   enable researchers to understand the technique(s) used to produce the data, which may include
   instrument description and data processing documentation, sufficient to enable determination of
   the accuracy, precision, uncertainties, and reliability of said data. Subject to national and
   international intellectual property rules, non-restricted scientific software should be similarly
   archived and made openly available.
9. These Guidelines intend to encourage use of existing universal data and software standards,
   where needed and appropriate, and to develop new universal standards in collaboration with the
   Heliophysics community, National Space Agencies, or international organizations, such as the
   International Organization for Standardization (ISO) or COSPAR, as appropriate.
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   Section 4 – Implementation
10. These Guidelines encourage the best practices of coordinating:
    a. Heliophysics-related sciences; and
    b. Efforts to address the challenge of making heliophysics research useful for space
    weather operations and applications. This would include addressing transitioning
    heliophysics research to operations/applications, distinguishing between the research
    and operations/applications, and encouraging the current and future generation of
    heliophysicists to invest in and develop these capabilities.
11. Coordination of best practices include sharing agency plans, identifying research and
    measurement gaps, resolving overlapping efforts, considering suborbital, ground-based, and
    space-based collaborative opportunities, considering recognition of the elements of the
    Guidelines, and periodically assessing the elements of the Guidelines.
12. Coordination of best practices would also include Space Weather discussions within existing
    operational Space Weather coordination entities including, but not limited to, the World
    Meteorological Organization (WMO), Coordination Group for Meteorological Satellites
    (CGMS), and the International Civil Aviation Organization (ICAO).
    Section 5 – Conclusion
    COSPAR is to maintain the original text of these Guidelines.
    Published on 4 November 2025 in the English language.
    As of 27 November 2025 the following space agencies and organisations have endorsed the
    Heliophysics Guidelines:
     National Space Science Center of the Chinese Academy of Sciences (NSSC-CAS)
     Solar Physics Division of the American Astronomical Society (SPD-AAS)
     the Space Studies Board of the National Academies of Sciences, Engineering, and Medicine
    (NASEM-SSB)
     the Space Physics and Aeronomy Section of the American Geophysical Union (SPA-AGU)
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     Cyprus Space Exploration Organization (CSEO)
     Istituto Nazionale di Astrofisica (INAF)
     Canadian Space Agency/Agence spatiale canadienne (ASC-CSA)