The Solar System

The southern hemisphere of Mars is quite heavily cratered and resembles the surface of our Moon. The surface is old and has been relatively unchanged for some time. The northern hemisphere is quite different. It has few craters and these appear far less eroded indicating they are much younger than those of the southern hemisphere. The northern hemisphere shows much geologic activity. The surface has been smoothed by repeated lava flows indicating a great deal of volcanic activity. There is also a lot of deformed uplifted crustal sections along with collapsed depressions. Martian volcanoes are the shield type like the Hawaiian islands on Earth. In these type, the lava flows freely and the lava flow can cover a tremendous area. The largest volcano on Mars is Olympus Mons. This volcano is a massive structure, with a base 600Km (370 mi.) across and towering 25km (16 mi.) high. This dwarfs Mauna Loa in Hawaii, the largest volcano on Earth which is only 10 km (6 mi.) high and 225 km (140 mi.) in diameter. Mauna Loa is so heavy it has actually sunk into the Earth's crust and formed a moat around itself. Olympus Mons does not show any sign of sinking and leads to the conclusion that the Martian crust is much thicker than Earth's. The entire region around Olympus Mons appears to be an uplifted volcanic plain, called the Tharsis region. There is a similar uplifted region called Elysium region which appears to be older than the Tharsis region. The Elysium region is cratered and eroded and has probably not been active for about 1.5 billion years. The Tharsis region may have been active as recently as 0.2 billion years ago. The Tharsis region contains another interesting geologic feature. There are numerous faults and one incredibly huge valley known as Valles Marineris (named after the Mariner spacecraft which discovered it.) The valley is nearly 4000 km (2500 mi.) long, and at its widest nearly 220 km (120 mi.) wide. If the valley were placed on Earth, it would stretch from New York City to Los Angeles. At its deepest is reaches 5 km (4 mi.) over four times the depth of the Grand Canyon! Valles Marineris appears to be the beginnings of what would have been crustal plate boundaries. Apparently the crust thickened and solidified before the plates could fully form. What is truly amazing is that Valles Marineris stretches nearly two-thirds the way across the planet. Such large geologic features like Marineris and Olympus Mons would not be possible on a larger world with higher gravity and thinner crust like the Earth. http://starryskies.com/solar_system/mars/mars_surface.html

Mars is about half the size of Earth in terms of diameter.

Yes.

It is very likely that the universe is packed with life all over the place, but the problem is that traveling across space involves such massive distances and difficulties that it is very hard to find and make contact with other places beyond our solar system.

Man has only been exploring space for 50 years and so we are still really only just at the beginning of seeing beyond earth. We have only sent men to the moon so far and that is very close.

If we wanted to visit planets beyond our own solar system then we would have to develop much better and faster technology to travel to other places outside of our solar system before we could look for life elsewhere.

The reason why there is life here on earth is because our planet is not too close to the sun to be too hot and not too far away to be too cold - life is very fragile and so our temperatures have to be just right as we orbit the sun otherwise life could not survive. But this means that statistically with all those other stars out there - millions and billions of them - there must be other planets orbiting other suns that are at the same distance that we are and so there would be a great chance of life also existing on those planets as well.

Our solar system is located in the thin disk of the Milky Way.

The discovery of hot Jupiters has challenged our understanding of planetary formation in our own Solar System. Their presence suggests that the processes that lead to the formation and migration of giant planets may be more complex and varied than previously thought, leading scientists to reevaluate existing models of planetary formation and migration.

No, a star is not a part of our solar system. Our solar system consists of the Sun, planets, moons, asteroids, comets, and other celestial bodies that are gravitationally bound to the Sun. Stars are distant celestial objects that are not part of our solar system.

Most of the Outer Planets beyond the Astroid Belt are made of gas, except for Pluto (if you consider Pluto to still be a planet). Jupiter, Saturn, Uranus, and Neptune are all made out of gas, but they do have particles of rock and ice surrounding them, too.

Venus and Earth are called "Sister planets" but if you've noticed Venus is bigger than Earth so therefore Venus is the biggest planet.

Yes, the planets revolve around the sun due to its gravitational pull, which is the strongest force in our solar system. This pull keeps the planets in orbit around the sun, following elliptical paths.

Solar is a term used to define anything that relates to the sun. Solar panels and heat, relies on energy from the sun.

The Sun contains the most mass in the solar system because it formed by accreting most of the gas and dust in the early solar system. The intense gravitational forces in the core of the Sun generate high temperatures and pressures that lead to nuclear fusion, producing energy and maintaining the Sun's structure. Other objects in the solar system, like planets and asteroids, have significantly less mass compared to the Sun.

The amount of Hydrogen it gets-? that doesnt answer anything.

the sun is what gives life a chance to grow (we couldn't grow food without it) and its what keeps us in the solar system, without it the earth probably wouldn't have formed and we wouldn't be orbiting anything.

The coldest planet in our solar system is Neptune, which has an average temperature of around -353 degrees Fahrenheit (-214 degrees Celsius). This extreme cold is due to its distance from the Sun and its thick atmosphere of gases, including methane and ammonia, which trap heat very effectively.

No, nobody uses the term "solar galactic hypothesis". You may be referring to a "solar nebula", in which a cloud of gas and dust collapses under its internal gravity to form a star and perhaps some planets.

There are eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. There used to be 9 planets, but Pluto was "plutoed" (a word that now means "demoted") and is now called a "dwarf planet."

There are 4 other dwarf planets: Ceres, Eris, Haumea, and Makemake.

Earth is the third closest planet to the Sun, orbiting at an average distance of 150 million kilometers (93 million miles). The closer planets are Mercury and Venus.

Copernicus did a lot of work to produce a model of the solar system with the Sun at the centre, which Galileo used to start a damaging dispute with the Pope, because he said it was not just a model, it was the truth, thus stepping over the barrier between science and religion (and he had no proof, as he finally admitted).

After Newton's time it was realised that the Sun is 330,000 times more massive than the Earth so it must be at rest in the centre, and now that is accepted as the truth.

it has two moons... they are called phobos and deimos

A large system of stars and other bodies is known as a galaxy. Galaxies are vast collections of stars, planets, gas, and dust held together by gravity. The Milky Way is an example of a galaxy that includes our solar system.

Venus ranked third in size when scientists and astronomers still considered Pluto as one of the planets in the Milky Way Galaxy. Nowadays, Venus ranks second in size, after Mercury, just as it is seen on a map of the planets in there specified order (Mercury, Venus, Earth Mars, Jupiter, Saturn, Uranus, Neptune). If the planets were arranged in order from smallest to largest, they would be in this arrangement: Mercury, Venus, Mars, Neptune, Uranus, Saturn, Jupiter.

Pluto was demoted to dwarf planet in 2006.

Yes, Pioneer 10 left the solar system. It was launched in 1972 and became the first spacecraft to travel through the asteroid belt, sending back valuable data as it journeyed towards the outer regions of the solar system. Contact with Pioneer 10 was last made in 2003, when it was over 7.6 billion miles away.

Planetary system formation coincides with the process of star formation in which our Sun belongs to the generation of stars created 4.6 billion years ago, when our galaxy was roughly half its present age. A cloud of interstellar gas, dust, and ices containing several generations of material collapsed to form the nebula from which the Sun and the rest of our solar system grew. This collapse may have been triggered by a nearby supernova. Cosmologists believe that because the material in the nebula was rotating to some degree, not all of the nebular material fell directly into the central mass that would become the Sun. Instead, some of the material was confined to a flat, spinning disk, called a protoplanetary disk, around a young Sun. As time went on, the grains and ices in the disk bumped into and stuck to one another forming macroscopic objects with sizes on of order 0.01-10 meters, all orbiting in the same direction and same plane analogus to the rings around Saturn. As the objects grew larger, their gravitational forces increased, attracting more matter from the disk and gradually building kilometer-sized bodies called planetesimals. These planetesimals further collided and either shattered into fragments or merged producing larger objects. The gravitational pull of the largest planetesimals produced rapid growth to the size of small planets and formed the nuclei of the planets as we know them today.