Terrestrial planets are basically planets that share some common characteristics.
They are usually rocky in nature, relatively small, and have high densities.
The only terrestrial planet with a dense atmosphere is Venus.
**Some abbreiviations are used in the face sheets. They are listed below.**
ED- Equatorial Diameter
DFS- Distance From Sun
PO- Period of (Revolution or Rotation)
ST- Surface Temperature
Mkm- million kilometers
Mm- million miles
**The following are definitions of words to make things clearer to the reader.**
Revolution- when a celestial body makes a complete orbit around another body of equal or larger proportions
Rotation- when a celestial body completely turns on a set of axis
Day- a spacial day is defined as how long it takes from sunrise to sunrise
Mercury Facts
ED- 4,880 km (3,030 m)
DFS- 57.9 Mkm
PORevolution- 88 terrestrial (earth) days
PORotation- 59 terrestrial days
ST- 440*K (332*F)
Length of Day- 176 terrestrial days
Other-
Mercury has no atmosphere. It is also the closest to the sun, with the highest surface tempereature of all of the planets. Its weak magnetic field is believed to suggest that Mercury has a large molten core. Except for the addition of many elongated ridges, Mercury's surface resembles the Moon's, with many craters, basins, and plains.
Venus Facts
ED- 12,104 km (7,517 m)
DFS- 108.2 Mkm
PORevolution- 224.7 terrestrial days
PORotation- 243 terrestrial days
ST- 400*C (750*F)
Length of Day- 118 terrestrial days
Other-
It has been long known that Venus has a thick cloud cover, along with that a dense atmosphere. It is smaller than Earth, but scientists used to think that it was Earth's sister planet, in fact speculating that life might be found on it. But when probes landed, it was found that Venus's conditions were far too hostile to nurture any form of life. Venus has the most circular orbit, Pluto's being the most ecliptical. Venus' small craters inditcate that though it may be dormant now, the planet once had a very active volcanic history.
Moon Facts
(yeah I know it's not a planet but it's important neverthelesss!!)
PORevolution around Earth- 28 days
PORotation- 28 days
Approximate Age- 4.5 billion years
Other-
Because its PO Revolution, and its PORotation are the same, the same side of the Moon is always facing Earth.
To date, twelve Americans have landed on the Moon, performing expieriments and bringing back to Earth 382 kg (842 lbs) of Moon rock. The side of the Moon facing Earth is made up of two-thirds light colored, highly cratered highlands, and one-third dark, fairly smooth, less cratered plains. The dark plains are called maria because of their resemblance to seas. The marias theoretically were formed by lava flows. The craters were theoretically formed by the bombardment of the Moon with meteorites, and range in size from anywheres to 1,000 km (620m) and smaller. The Moon's surface is completely made of igneous rock, indicating that at one point in its history, its surface was completely molten, and that there were no seas of water ever in existance on its surface. The Moon's surface gravity is also unconsistent, and over some large, circular plains, there are mascons, which are concentrations of higher than normal density, which results in small increases in local gravity. The Moon is seismically inactive, and very little activity takes place on its surface. But by reading the waves off of small "moonquakes" which never reached beyond two on the Richter scale, scientists determined the crust to be approximately 60 kms thick. Underneath, for another 1,000 km is a solid mantle, with a core that is probably molten.
Mars Facts
ED- 6,788 km ( 4,218 m)
DFS- 227.9 Mkm
PORevolution- 687 terrestrial days
PORotation- 24 hrs, 37 min, 23 sec
Other-
Due to Mars' thin atmosphere, the surface of this planet is directly observable, and because of this, and its close proximity to Earth, it is one of the more explored of the planets. Mars has two satellites, Deimos (6m wide) and Phobos (10m wide), whose surface composition and physical characteristics resemble the asteroids that exist in the outer asteroid belt. Some scientists believe these two may be captured aesteroids. Mars has a very weak magnetic field, and many scientists theorize that it lackes a metal core. Mars has three distinct types of surface features. The first is the cratered area, that resembles the Moon. This area is very old. The next area is more recent, the chaotic, craterless jumble of short ridges and depressions. And the third is the featureless plains, lacking craters, ridges and even valleys. More than half of the planet is a desert like surface, and it isn't unusual for planet wide dust storms to stir up. Mars is home to several large volcanoes, including Olympus Mons, the largest volcano thus far discovered in the solar system. Olympus Mons is almost three times the size of Earth's Mount Olympus. The size of the volcanoes suggests that in certain areas, Mars has an unusually thick crust. Large canyons splitting the surface of Mars suggest the theory that water, long since having escaped the planet, once flowed on the surface. Mars' polar caps go through a seasonal increasing and descreasing of size, something that so far has baffled scientists, who hope that long-term, intensive observation will explain the phenomenom. Mars has long since been suspected of once having supported life, but to date, no solid evidence has been found. Weather conditions on Mars appear to be less variable than on Earth, and in fact, they seem to vary regularly among the Martian day. Weather also affects Mars' air pressure, and in seasonal rotations, the atmospheric pressure may increase up to 30%.
