THE PLANETS Goal: To learn (review?) basic information about the 8 planets and the minor planets of our solar system. Please be in your seat and have a pencil or pen.

Notebooks FYI – we will be beginning Geology soon, so if you do not have a notebook anymore (for whatever reason), or your old one is filling up, you will want to get a new one by MONDAY, Feb 3. I do not have many more to hand out, so if you need assistance acquiring a notebook, please talk me after class or your counselor.

If I asked you to shut your eyes & think of the solar system, what do you see?

Size & Distance Most diagrams of our Solar System are not to scale Also, most diagrams do not include the “minor planets” or the Asteroid Belt. You’ve studied the Solar System in lower grades, so this is just a review. We will create a chart for this information, but first, look over the next few slides and keep these in mind while we’re working on this lesson.

Scaled sizes of planets

Distances – notice it stops at Saturn!

Planets & Dwarf Planets click below FOR a 3:20 video

Planets There are eight planets The “Inner Planets” – Mercury, Venus, Earth, & Mars are also called “Terrestrial Planets” (Terra mean soil)

Planets The “Outer Planets” – Jupiter, Saturn, Uranus, & Neptune are also called “Gas Giants”

Dwarf (or Minor) Planets There are three: Ceres, Pluto, and Eris Ceres is the smallest and is located in the Asteroid Belt between Mars and Jupiter You know about Pluto, formerly considered the ninth planet, now known officially as asteroid #134340 Eris is an ice ball, officially knows as 2003 UB313. It was originally nicknamed Xena after a TV character. These changes happened in 2006

Your chart: “Our Solar System” Keep your paper in “Portrait” Use the ruler to draw a line about every 1.5 inches You can sketch and color picture of the planet It’s OK if you need to continue on the back of the paper – Headings +8 planets + 3 dwarf planets + 5 others = 16 rows (make 2 columns) Planet/ Bodies Information Mercury No atmosphere 88 day orbit 8000F to -3000F

Mercury Mercury has virtually no atmosphere. It however has small traces of an atmosphere . It takes less than 88 Earth days for Mercury to orbit around the sun which is its year. Because of a lack of an atmosphere, the temperature rises above 800°F while on the dark side it falls rapidly to -300°F. Mercury rotates slowly on its axis. It completes one rotation every 59 Earth days which is its day. The surface of Mercury is heavily cratered, looking much like our moon. Mercury does not have a natural satellite (a moon)

Mercury

Venus Its atmosphere is made up mostly of carbon dioxide which causes a run away greenhouse effect and the planet is around 900 degrees F. It is the hottest planet. It takes 243 days to make a rotation and it takes 224 days to orbit around the sun. This makes its day longer than its year The planet rotates from East to West which is called retrograde rotation. Venus does not have a natural satellite (a moon)

Venus Click for 2 min video on atmosphere ->

Earth It is made up of approx. 70% water Only planet known to contain life The densest planet Day = 24 hours Year = 365.25 days

Earth

Mars It is red because there is a lot of iron in the soil Mars year = 687 Earth days. Nighttime temperatures on Mars can drop as low as -191°F. The thin atmosphere is made of mostly carbon dioxide. Mars has seasons like Earth. Mars has two moons.

Asteroid Belt The Asteroid Belt is a region between the inner planets and outer planets where thousands of asteroids are found orbiting around the Sun. More than 7000 asteroids have been discovered. Several hundred more are discovered each year. There are undoubtedly hundreds of thousands more that are too small to be seen from the Earth.

Click above for NASA’s Dawn Mission to the Asteroid Belt 1:34 mins Click above for NASA’s Dawn Mission to the Asteroid Belt 1:34 mins. Dawn (as of Dec 2013) is halfway from Vesta to Ceres.

Ceres This dwarf planet is one of the largest asteroids in the Asteroid Belt Scientists describe Ceres as an "embryonic planet." Gravitational perturbations from Jupiter billions of years ago prevented it from becoming a full-fledged planet. Ceres ended up among the leftover debris of planetary formation in the main asteroid belt between Mars and Jupiter.

Jupiter It rotates faster than any planet making the days only 10 hours long. It is the largest planet. Its has 67 confirmed moons! It has the biggest moon in the Solar System, Ganymede. It has a ring. The Great Red Spot is a storm that has been going on for over 300 years. The Great Red Spot is large enough to contain 2 to 3 planets the size of Earth

Click below for 2:19 video from Bill Nye on Jupiter’s storm) Jupiter and moons

Saturn It has the lowest density of all the planets. It has over 60 known satellites Its rings are made up of billions of pieces of rocks, ice and dust. Titan is the only Saturn moon with an atmosphere.

Saturn

Uranus Uranus is the coldest planet in the solar system. It is tilted completely on its side so the equator runs north to south because of impact from an asteroid . It is the blue-green planet because of its methane gas. It has rings.

Uranus

Neptune Neptune is the stormiest planet. The planet has a system of thin dark rings . Neptune has 8 known moons.

Neptune

Pluto click below for 3:31 video about minor planets Pluto, is now considered a "dwarf planet." A dwarf planet orbits the sun just like other planets, but it is smaller. A dwarf planet is so small it cannot clear other objects out of its path. Pluto travels an oval pathway around the Sun. The dwarf planet has three moons. Its largest moon is named Charon (KER-ən). Charon is about half the size of Pluto.

More Dwarf Planets There are more dwarf planets – most beyond Pluto’ Some have tiny moons

Meteoroids & Meteors Meteoroid - any of the small solid extraterrestrial bodies that hits the earth's atmosphere Meteor - a streak of light in the sky at night that results when a meteoroid hits the earth's atmosphere and air friction causes the meteoroid to melt or vaporize or explode Meteorite – any part of a meteoroid that survives the fall and reaches the planet’s surface

Asteroids The Asteroid Belt is between Mars & Jupiter, but asteroids can be anywhere in the solar system. A class of small bodies in orbit around the sun. They are smaller than planets & sometimes called minor planets or planetoids. They’re bigger than meteoroids.

Comets a relatively small extraterrestrial body consisting of a frozen mass that travels around the sun in a highly elliptical orbit click below for NASA video 3:06 mins

Kuiper Belt and Oort Cloud The Kuiper Belt and the Oort Cloud surround our sun, a star. The Kuiper Belt is a doughnut-shaped ring, extending just beyond the orbit of Neptune from about 30 to 55 AU. The Oort Cloud is a spherical shell, occupying space at a distance between five thousand and 100 thousand AU. The first mission to the Kuiper Belt is New Horizons spacecraft. New Horizons was launched in 2006 and will reach Pluto in 2015. Click below for 4:40 min video

Xena was renamed “Eris” in 2006 The Earth is shown for size comparison

What else is out there? It seems unlikely that other planets in our Solar System support life. SETI, the “Search for ExtraTerrestrial Intelligence” is an independent non-profit. The mission of the SETI Institute is to explore, understand and explain the origin, nature and prevalence of life in the universe.

Any Questions?