THE SUN'S FAMILY

Mercury

Planet in our solar system nearest the sun

surface gravity

The force of gravity which determines the weight of a body at the surface of a planet.

Jupiter, Saturn, Uranus, and Neptune, are called:

the outer, or Jovian planets.

The sun's family have how many asteroids?

thousands

The sun's family have how many dwarf planets?

three(3)

the inclination of the axes of the planets have a ___________________.

wide variation

1971

A Russian probe, Mars 3, made the first soft landing on Mars, but after 20 seconds it stopped transmitting information.

1997

After a seven-month journey from the Earth, Pathfinder landed on Mars on July 4, 1997. The Pathfinder spacecraft contained a small rover called Sojourner which roamed the Martian terrain, sending back video images as well as spectrographic analysis of rocks and soil. The landing site was in a dry flood channel called Ares Valles. Geologic evidence seems to indicate that catastrophic floods once ran through the landing site. The details of many surface features on Mars indicate that the planets surface has undergone massive erosion by flood waters at some time in its history. Geologic features such as shorelines, river channels and tear drop shaped erosion remnants are evident. Although the remnant of some of the water can be seen in the frozen ice caps at the Martian poles, scientists are uncertain where all the water has gone. Perhaps it is located underground or now consists of ice crystals within the Martian soil. The Earth's geologic history also reflects the evidence of a massive flood in the past. Apparently, global flooding has not been confined to the Earth alone.

asteroid

Any of thousands of small objects that revolve about the sun, chiefly between Mars and Jupiter's orbits; planetoids.

two other dwarf planets have been recognized ____________ and ___________

Ceres and Eris

2011

Curiosity Rover. NASA's Mars Science Laboratory (MSL) spacecraft was launched on November 26, 2011 carrying with it the newest Red Planet Rover, Curiosity.

To be classified as a planet, a celestial object must meet three criteria.

First, it must orbit the sun. Second, it must have enough mass for its gravity to pull its matter into a rounded shape. Third, it must orbit the sun in a clear path unobstructed by other celestial bodies.

Planets and stars look much alike in the night sky, but planets have two distinguishing characteristics:

First, the planets shine with a steady light, but the stars seem to twinkle. Second, the planets change positions and directions in relation to the stars.

Neptune

Fourth largest planet and farthest from the sun.

Jovian Planets

Jupiter, Saturn, Uranus, and Neptune.

Jupiter

Largest planet in the solar system. It is fifth in distance from the sun.

1965

Mariner IV sent back photographs of meteor craters.

1971-1972

Mariner IX orbited Mars photographing both moons, a dust storm, and many surface details.

1969

Mariner VI and Mariner VII photographed the surface.

2002

Mars Odyssey Orbiter. The Orbiter showed large amounts of subsurface water ice in the northern arctic plain.

The order of the planets, beginning closest to the sun, is:

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.

Venus is the most brilliant of all the planets and is called the

Morning Star when seen before sunrise and the Evening Star when seen after sunset.

Pluto's elliptical orbit brought it closer to the sun than_________ in January ________ . They remained in this order until 1999.

Neptune 1979

The order of the planets, beginning from further to the sun is:

Neptune., Uranus, Saturn, Jupiter, Mars, Earth and Mercury

Pluto

Once considered a planet, Pluto is now one of the dwarf planets in our solar system, discovered in 1930.

comet

Orbiting body with a bright center and a cloudy tail of dust which always points away from the sun.

Mars

Planet next in order beyond the Earth. The seventh largest planet, notable for its red color.

Saturn

Second largest planet, and sixth from the sun. Encircled by a system of rings made up of particles of ice.

Uranus

Seventh from the sun; the planet found through mathematical calculation and prediction.

Venus

Sixth largest planet, second from the sun. Orbit is nearest to the Earth. Often called Evening Star or Morning Star

2007

The Phoenix. The Phoenix spacecraft was launched on August 4, 2007 and successfully landed on Mars on May 25, 2008. Its mission was to land in the north polar region of Mars and its mission is to dig through the protective top soil layer to the water ice below and ultimately bring both soil and water ice to the lander platform for scientific analysis. The Phoenix mission has two bold objectives to support the goals of NASA's long-term Mars Exploration Program and that is (1) to study the history of water in the Martian arctic and (2) search for evidence of a habitable zone and assess the biological potential of the ice-soil boundary. More Information on this and other missions can be obtained by going to the nasa.gov website.

terrestrial planets

The four planets nearest the sun; somewhat similar to the Earth.

solar system

The sun and all its planets, satellites, comets, and other heavenly bodies that revolve around it.

1976

Viking I and Viking II landed on Mars. They sent back images of the surface. The surface is red because it is rusty. There is a lot of iron in the rocks. It has combined with oxygen from the air to make rust. Both Viking probes had sophisticated equipment to test for evidence of life within the Martian soil. The results were very disappointing to those scientists who believe that life can evolve (create itself) from non-living chemicals. No evidence of life was found.

Venus's have a :

atmospheric pressure is 1,300 pounds per square inch.

The sun's family have how many meteoroids?

countless

The planets are _______ and ____________ bodies, much smaller than the __________.

dark,relatively cold, sun

Pluto orbits the sun inside a disk-shaped region of ice and rock called the Kuiper (pronounced Ki-Per) Belt. Since it does not have a clear orbital area, Pluto is considered a

dwarf planet

The sun's family have how many planets ?

eight(8)

Comets travel in ______________ or ______________ paths around the sun.

elliptical , parabolic paths around the sun

these variations and more do not harmonize or "fit" into the

evolutionary theories of the origin of the solar system from a common cloud of dust and gas.

Because of the long length of the Mercurial day, the temperatures on Mercury are

extreme

The sun and the stars are:

giant spheres of hot gases

The feature that all members of the sun's family have in common is their:

gravitational attraction to the sun while they travel with the sun through space.

The stars produce their own ______ and ______ , but the planets do not.

heat, light

Mercury, Venus, Earth, and Mars are called :

inner, or terrestrial planets.

What is retrograde motion?

is when satellites rotate in the opposite direction from the orbit of their planets

The sun's family have how many comets ?

millions

Jupiter, Saturn and Neptune have satellites which rotate in the

opposite direction

Venus, Neptune and Pluto (a dwarf planet) rotate in an

opposite direction to the remaining planets

The sun's family consists of:

planets, dwarf planets, moons, asteroids, comets, and meteoroids.

The sun's family have how many moons?

sixty(60)

All light and nearly all heat on the planets comes from the:

sun.

The planets can be seen only because they reflect

sunlight.

Earth and the three other planets nearest the sun are somewhat similar. They are called the

terrestrial (Earth-like) planets

Pluto, a dwarf planet, is probably like the____________________________ but it is too _________ to be seen in detail

terrestrial planets far away

Inner and outer planets are separated by

the asteroid belt.