- The inner planets are Mercury, Venus, Earth, and Mars.
- Close to the Sun and separated from the much larger Outer Planets by an asteroid belt.
- Sometimes called terrestrial planets and are composed of rock.
- Due to their hard surfaces, these planets have canyons, craters, mountains, and volcanoes.
- Few or no moons.
- Developed from small grains of dust that collided and formed together.
I found a very nice flash piece on another website that shows the relative speed of these planets in orbit around the sun. Click here to view it.
Earthshine is sunlight that bounces off of the earth and onto other objects in space. A study was performed to measure the difference of the amount of earthshine coming from the continents on Earth as compared to the amount of earthshine coming from the oceans. It was found that the shine from the oceans was quite intense compared to the dimmer shine from the land masses. They determined this by taking pictures of the dark side of the moon (where light from our sun never hits) at various times over a three-year period. As a result, they could measure the amount of earthshine from the continents hitting the moon and the amount of earthshine from the oceans.
This certainly sounds reasonable. Anyone that has been out on the water found out that it is easy to get sunburnt even when staying under a cover. The water will reflect light at you from below despite being shaded from the sun above.
Scientists may be able to use this information when looking for another habitable planet around other stars in the universe. Any planet we will be looking at will be too far away for us to get a good look at its surface. However, we might be able to view the amount of shine generated from the planet onto other objects nearby. It could provide clues to the physical make up of the planet.
Once we humans have made this planet uninhabitable for ourselves, we'll need to move somewhere else to survive. Unfortunately, I don't think our space traveling abilities will advance fast enough to allow us to move some place else, even if we are lucky enough to locate a destination.
Resource: University of Melbourne (2009, April 8). Earthshine Reflects Earth's Oceans And Continents From The Dark Side Of The Moon. ScienceDaily. Retrieved April 9, 2009, from http://www.sciencedaily.com /releases/2009/04/090407105156.htm.