Geology of solar terrestrial planets Earth, and Mars) have substantial atmospheres; all have impact craters and tectonic surface features such as rift valleys and volcanoes. The term "inner planet" should not be confused with "inferior planet", which refers to any planet that is closer to the Sun than the observer's planet is, but usually refers to Mercury and Venus. The Solar System is believed to have formed according to the nebular hypothesis, first proposed in 1755 by Immanuel Kant and independently formulated by Pierre-Simon Laplace. This theory holds that 4.6 billion years ago the Solar System formed from the gravitational collapse of a giant molecular
Sustain Our Planet analysis and a list of recommendations on how a business might reduce its carbon footprint over time. Sustain Our Planet's Green Schools Program is an online teaching resource for children and educators interested in learning and practicing techniques that help protect the planet. This downloadable teaching resource contains green lesson plans, environmentally themed experiments, and green classroom activities on the carbon cycle, saving energy, recycling, and endangered animals. All content compliments the National Standards set by the US Department of Education for Science, English and Art. Sustain Our Planet Sustain Our Planet is a consulting firm that provides carbon calculation