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Space Weather and its Planetary Connection: Future Interplanetary Travel Norma B. Crosby1 and Volker Bothmer2 Belgian Institute for Space Aeronomy, Belgium Institute for Astrophysics, University of Göttingen, Germany 1 2 Credits: ESA http://meetings.copernicus.org/epsc2006/index.html The first “European Planetary Science Congress” was held in Berlin, Germany from 18 to 22 September 2006, its aim being to cover a broad area of science topics related to planetary science and planetary missions. Ideal platform to link traditional near-Earth space weather studies to planetary studies - in this way the workshop session “MA4 Interplanetary Space Weather and its Planetary Connection” was organized (N. Crosby and V. Bothmer): - Oral presentations: 14:30-16:30 - Coffee/Tea break: 16:30-17:00 - Discussions [ brainstorming session ]: 17:00-19:00 MA4 Oral Presentations Solicited Talks: Solar Energetic Particles: the Current Status of their Origin and Space Weather Effects (Mikhail Panasyuk) Radiation Protection for Manned Interplanetary Missions – Radiation Sources, Risks, Remedies (Rainer Facius) Contributed Talks: The Relationship of Satellite Anomalies and Launch Failures to the Space Weather (Natalia Romanova) Galactic Cosmic Ray Composition, Spectra, and Time Variations (Mark Wiedenbeck) Space Weather Effects on the Mars Ionosphere due to Solar Flares and Meteors (Paul Withers) Session MA4 – Brainstorming Session from 17:00-19:00 Today in Lecture Room: Straßburg Interplanetary Space Radiation environments Technical and biological effects Timescales of radiation exposure as a function of energy and effect (technical and biological). Atmospheres on other Planets With/without magnetospheres. Mitigation Techniques Shielding (in space and on other planets) Forecasting Detector technology. Why go Interplanetary ? Manned missions to other planets Colonies on other planets (e.g. Mars) Mining on other planets, moons, asteroids Space tourism - Space hotels Terra-forming Transportation technology development (propulsion, nuclear, etc.). Why go Interplanetary ? – cont. For interplanetary travel a strong understanding of space weather is essential. interplanetary space weather (inter-disciplinary) supports all space weather projects one form of space weather research can not live without the other (they complement each other). The Perils of Interplanetary Travel Space Weather from Earth’s Perspective Our location in the solar system. Earth’s magnetic field shields us against highenergetic particles. http://www.nineplanets.org/ Behavior of the Sun, Nature of Earth’s magnetic field and atmosphere. Images from NASA The Perils of Interplanetary Travel 3. Solar Proton Events 2. Galactic Cosmic Rays AURORA Programme. Courtesy of ESA. 1. Earth’s Radiation Belts Courtesy of NASA's Solar Connections Home Page. The Perils of Interplanetary Travel Major Radiation Environments in our Heliosphere Particle Populations Energy Range Temporal Range Spatial Range (first order) Galactic Cosmic Rays GeV - TeV Continuous Entire heliosphere Anomalous Cosmic Rays < 100 MeV Continuous Entire heliosphere Solar Energetic Particles keV-GeV Sporadic (minutes to days) Source region properties (CME evolution) and bound to CME driven shock Energetic Storm Particles keV-(>10 MeV) Hours-Day Bound to shock Corotating Interaction Regions keV-MeV few days (recurrent) Bound to CIR shock and compression region Particles accelerated at Planetary Bow Shocks keV-MeV Continuous Bound to bow shock eV-couple of hundreds of MeV Variations “minutesyears” Variations “height-width” Trapped Particle Populations - Electromagnetic radiation (e.g. UV, X-ray, γ-ray) - Plasma (energetic (keV) and low-energy (eV)) - Neutrals (Space debris and meteoriods) Avoiding Space Weather Hazards There exists various approaches: 1. Space Weather Forecasting « Warning Guidance » 2. Mitigation shielding 3. Hazard Assessment The key of understanding radiation protection requires knowledge about the space environment and particle interaction with shielding materials. An important issues concerning shielding is the problem of secondary radiation in materials. - New forms of shielding materials are imagined and more impetus should be placed on polymer research in regard to the development of resistant light weight shielding. - Of course the faster the trip the better, i.e. development of innovative transportation technologies and new propulsion systems as well as orbit optimization are highly important. (EXCESSIVE MASS, SIZE and COST) Avoiding Space Weather Hazards Spacecraft shielding requirements, including space storm shelters, both on the spacecraft as well as radiation protection facilities on the target (e.g. Moon, planet), need to be taken into consideration with respect to travel time, local target space weather conditions and the phase of the solar cycle. It is therefore recommended, especially for a flight to Mars to implement onboard forecasting capabilities. Avoiding Space Weather Hazards Timing of an Interplanetary Space Mission The biological effect of a radiation dose received over the time period of a week is less dangerous than if the same dose is received instantaneously (e.g. in a few hours). Long-term radiation effects (5-30 years after) from exposure are still not known. The ultimate goal is to minimize radiation health effects by maximizing orbit parameters and shielding. Feasibility to use and Integrate Existing Systems Four parameters describing the scenario: telecommunications (signal travel time, 3.1 up to 22.2 min.) Target’s position (e.g. Mars) with respect to Sun and Earth Estimation of solar energetic particle event hazards Mars-Earth phasing (56 – 400 million km). (Glasstone, 1968) Requirements for the detection of back-sided CMEs (tentative particle events) when Mars is on the farside of the Sun: Courtesy of SWAN/SOHO. Space-based coronograph observations from ISS type observatories, LEO, L1 or STEREO-like orbits (during some phases of the solar cycle back-sided CME source regions may be located via helioseimological techniques). Feasibility to use and Integrate Existing Systems While envisioned manned modules for future space missions to Mars are generally equipped with shielded astronaut shelters, adequate warning is necessary for these to be useful. SPE GO TO SHELTER Effective forecasting capabilities are important for shortterm objectives such as being able to predict a solar energetic particle event before an astronaut exits the protection of a spacecraft. SPE HELP ! On the other hand space weather monitoring is essential for the understanding of the long-term variations observed in the space environment – the “space climate”. This type of information is extremely important in the designing of spacecraft - assurance of operational safety. Target Space Weather Conditions Once our target has been reached, it is important to know the local near-target space weather environment. Planets without a substantial internal magnetic field such as Mars are for example not shielding energetic particles such as Earth does. For any colony on Mars the mitigation of such particles will be vital for the health of people staying for extended periods of time. Like on Earth, enhanced ionization due to solar radiation (UV and X-ray) in a target’s atmosphere may cause communications problems. Final Words There are differences between near-Earth space weather and the local space weather on targets elsewhere in our solar system. However, space weather knowledge is fundamental for helio-space weather conditions. Different scientific communities need to interact with each other. It is important that more interaction between the traditional planet and solar-terrestrial physics communities occurs in the future. This is possible not only by collaborating on projects but also by participating in each others meetings. Acknowledgements Louis J. Lanzerotti Editor AGU Space Weather Journal • Mikhail Panasyuk Skobeltsyn Institute of Nuclear Physics of Moscow State University, Moscow, Russia • Rainer Facius DLR, German Aerospace Center, Inst. of Aerospace Medicine, Division Radiation Biology, Cologne, Germany • Natalia Romanova Institute of the Physics of the Earth, Moscow, Russia • Mark Wiedenbeck Jet Propulsion Laboratory, California Institute of Technology, California, USA • Moussas Xenophon University of Athens, Laboratory of Astrophysics, Athens, Greece • Jean-Mathias Greissmeier Observatoire de Meudon, Meudon, France The Perils of Interplanetary Travel Space hotels might one day become popular vacation spots. SPACE HOTEL 21-11-2036 -------------------------CUSTOMER COPY RECEIPT Photo courtesy Space Island Group