Astronomy 101

The view we have of the sky constantly changes. It is like we are in a goldfish bowl, spinning around, in constant motion. Everything seems as though it is moving, because we are on a ball that is enormous. It is known as the celestial sphere.

This creates a celestial grid. Lines that join the grid are measured in time and are known as right ascentions while parallel are known as Declinations and are measured in degrees. The line directly above the equator is the celestial equator and is 0 degrees. Northern position are positive and southern are negative and the highest degree they both have are 90.

Mercury

It's the closest planet from the sun, at only 36 million miles. Only one space probe has visited Mercury 30 year ago. It experiences a drastic contrast in temperature, the side facing the sun is a whooping 800 degrees, while the side away is a detrimental -2900 degrees.

It has some reflective areas which are probablyice from meteors.  Some of Mercurys never recieve any sunlight.

The length of its day is 59 of Earth days while its year is only 88 days. It has a ninety degree axis, which means it does only have one season.

Mercury has large amounts of iron which explains it red color. Caloris Basin is the ring of mountain, which is in many of the pictures of Mercury. The mountains are 807 miles high. Europe and Japan plan to have a joint mission to Mercury in 2013.

Mars

Mars is a much smaller, red version of the Earth. The most probes have visited it, out of all the planets in our Solor System and they still do. Mars has a diameter of 4, 222 miles.
Mars has a rocky crust as well as unbreathable methane atmosphere, which is Methane gas. The crust is red from the rust it has.

It's day is 40 minutes longer than a day on Earth. It has a year which is twice as long. Mars has a 25 degree tilt. This planet haso water reserves left from a few of the astroids. The largest mountain is called Olympia Mons. It has the biggest volcano range.

An area near the equator has a frozen sea. Water is still present on Mars. The poles hold enough water to cover the planet with 36 feet. The moons appear to be trapped by the magnetic core. One moon, Phobos, is 16.8 feet long, while the other, Deimos is 9.3 miles long.

Sun

This star is ours. It is about 854,590 miles in diameter. It is 50 times the size of Jupiter. 10 million earths could fit within it. It has 7,000 million tons of hydrogen which turns into helium every second.

This star burns like a furnace. The core could have a temperature of at least 60,000,000 degrees. The surface is called the photosphere. It gets acne which is called a Sunspots. Facvlea are bright rivers within the sun. Coronal mass ejections hurl vast amounts of energy into space.

Moon

The moon is the only natural satellite that the Earth has. Its landscape has barely changed in over one million years. It's 240,000 miles from the earth. The diameter is only 2160 miles. It has ice from comet impacts.

The moon has 6% of the amount of gravity that the earth has. Soil is on the moon. It is called "regolith." This is a Greek term, which means unconsolidated, residual and transported material that overlays solid rock.

It's rotation varys, because of its oval orbit. It varys from 25-10,000 miles from Earth. By the year 2020 NASA as well as ESA (European Space Association), plan to have a base there.

What if a blackhole formed near our Solor System?

<p>Surviving a near miss with a blackhole is like surviving the Titanic. You would freeze to death, if you survived the crash. You would be in the unknown. This would be exciting to some, and scare others to death. </p>
<p>They are the most fearsome phenomena within the universe. In essence, they a gigantic vaccum within space time. Our sun would never become one, for it is to small.

Could One of these Planets be the Home of ET

The most Earth like planets are often not the most welcoming for life. There doesn't have to be water as we know it present.

Titan, Mars then Gliese 581D filial Earth in ability to support life. Titan has a vast lake of liquid hydrocarbons and has a surface temperature of negative 300 degees.

Gleise 581D is the only exo-solor planet astronomers consider Earth-like because it is rocky and orbits a cool dim star.