Our space environment: opportunities, stakes and dangers

Introduction. Setting the scene. Characteristics of our space environment (Near-vacuum - Zero-g or microgravity - Other features of the Earth gravity environment - Radiation balance - Radiation and particle flux from the Sun and the Galaxy - The Earth`s magnetosphere). Utilization of our space environment for practical purposes, science and exploration. Rewards and Power of Space. Unweiling the mysteries of cosmic lights (Incredible Solar System - What has space taught us? The mysteries of darkness - Plurality of worlds and universality of life). Observing Earth`s skeleton and skin, surveying its health, monitoring its aging (Observing tools - Forecasting, facing, and managing Earth - First steps toward a global space governance for Earth monitoring). Influence of outer space on the Earth. The Sun (Living 8 light-minutes away from a cosmic nuclear furnace - The magnetic active star - Sun`s influence on Earth: the Carrington even - Space Weather)- 3.2 Weather and Climate (The four step dance of planet Earth - Sunlight influence on climatic modulations - The Sun and the atmosphere: a vital interaction - The influence of volcanic and solar activities- Future natural climate influence). Asteroids and Comets, (The Near Earth Object Impact Hazard - Observation, Detection, and Impact Prediction- Preventing an Impact - Way forward?). Impact of human activity on the near space environment.  Space Debris (What is space debris? - What do we know, how much space debris is there? - Why is space debris a problem? - What are the immediate countermeasures? - Where does the data come from? - Protecting the space environment - an international endeavor - Predicting the future - Long-term sustainability of outer space activities - International policies and requirements). Opportunities and limits for actors. Int