Transcript Chapter 11
We continue to learn a lot about the solar system by using space exploration The Sun Criteria Characteristics Mass Contains 300 000 times more mass than Earth Motion rotates Composition Contains hydrogen and helium atoms Function Chemical reactions in the sun give off electromagnetic radiation (including heat and light) which support life in our solar system Special Features Sun spots, solar flares and solar prominences The Sun Sun Spots: dark patches on the Sun’s surface that are slightly cooler, about 3500°C, than surrounding areas. The number of sunspots on the Sun may affect Earth’s climate, although it is still being debated The Sun Solar Flares: Extremely violent eruptions of gas from the Sun’s surface. These eruptions can last for a few hours and heat gases to 11 000 000°C. When these high energy particles rush past Earth they create an effect called solar wind Earth’s magnetic field deflects most of this dangerous solar wind The solar wind can disrupt Earth’s magnetic field, disabling satellites and even knocking out power transmission line on Earth. The Sun Solar prominences loops of super-hot gas that extend out from the sun’s surface Features of the Sun Planets Planet: a body that must orbit one or more stars, be large enough that its own gravity holds it in a spherical shape, and be the only body occupying the orbital path Terrestrial Planets: inner, rocky planets, Mercury, Venus, Earth, and Mars Jovian Planets: outer, gaseous planets, Jupiter, Saturn, Uranus, and Neptune Terrestrial and Jovian Planets Criteria Terrestrial Planets Jovian Planets Size Small (All Earth size or smaller) Large (4 to 11 times larger than Earth) Motion Slow spinning, small orbits Faster spinning, large orbits Composition Solid and rocky Gaseous Distance from Sun Closer Further away Temperature Warmer, but temperatures vary Colder, but temperatures vary Density Greater Lesser Planets… Closer to the sun, the temperature is warmer and the composition is solid and rocky Further from the sun, the temperatures are lower and the composition is gaseous. Order of the planets: My Very Educated Mother Just Served Us Nachos (Mercury, Venus, Earth, Mars , Jupiter, Saturn, Uranus, Neptune) Dwarf Planets Dwarf Planet is a celestial body orbiting the Sun that is generally smaller than a planet but massive enough for its own gravity to give it a round shape. Pluto, Eris and Ceres Question Why was Pluto demoted to Dwarf planet in 2006? Article Moons Orbiting companions of all the planets except Mercury and Venus More than 165 moons have been detected in our solar system Asteroids Asteroids are smaller bodies that are believed to be leftover remains of the formation of the solar system Most orbit the sun very similar to planets The main location for asteroids is in a band between Mars and Jupiter Some asteroids have irregular orbits due to gravitational attraction of the planets and collisions. Comets Comets are often referred to a “dirty snowballs” made up of ice, rock, and gas. They originate beyond the orbit of Neptune, at the farthest reach of the Sun’s gravitational influence. Here lies a spherical cloud of small icy fragments of debris called the Oort cloud. Comets are usually characterized by one or more “tails” due to a loss of dust and ice due to exposure to solar radiation (it starts to melt) Path of a comet around the Sun Comets and Periodicity Comets have unique orbits around the sun and tend to follow a pattern with regards to their passage by the Earth and Sun Two types of comets: Short and Long Period comets. Short period comets orbit the Sun faster. Periodicity: How long it takes a comet to orbit the sun Research Activity 11-2c: Comet orbits and periodicity Meteoroids: are pieces of rock floating through space Solar system debris Meteors: (“shooting stars”) are meteoroids that burn up as they enter Earth’s atmosphere at high speed Trail associated with meteoroids as they enter the atmosphere Meteorites: meteors that are large enough to survive passing through the atmosphere and they reach Earth’s surface. Compare and Contrast Criteria Asteroid Meteor Meteorite Size Sand grains to about 1000 km across Sand grains Larger than meteor Composition Pieces of Rock Pieces of Rock Pieces of Rock Location Mainly the Asteroid belt (between Mars and Jupiter) Earth’s Atmosphere On Earth When meteorites hit Earth Impact sites: the place where a relatively small object (meteorite) has collided with a large object (planet) to produce a fairly circular depression on the surface of the larger object. Often referred to as an impact crater due to the circular depression that was formed Impact sites provide evidence of meteor/asteroid impacts on a planet The size of the depression created is often much larger than the object involved in the collision. Impact Sites There is a NEAR earth monitoring system that monitors asteroids, comets etc. WHY? Go to: www.msss.com/small_bodies/near_new/index.html Solar Phenomena on Earth Solar Radiation All life on earth is dependent on solar energy in the form of radiation Ex: plants use solar radiation to produce food Solar Wind and auroras When high energy particles from solar flares rush past Earth they create an effect called solar wind Some of it enters at the North and South pole, collide with gases in the atmosphere and create the auroras (northern and southern lights) Canadian Contributions to Space Research Canadarm 1: robotic arm used to retrieve and launch many satellites and to give a stable platform for astronauts going about their tasks in space Canadarm 2: a mobile remote manipulator system designed for the International Space station. Able to do everything Canadarm 1 does but larger and able to move by itself to nearly every part of the station Canadian Contributions… Dexterous manipulator of Canadahand: a two armed robot that attaches to the end of Canadarm 2. Performs task that previously required astronauts to work outside the safety of the space station Canadian Contributions… International Space Station: Sixteen countries including Canada are involved in this space based laboratory. Canadian Astronauts Canada does not send missions into space but they provide technology and expertise to space exploration. Astronaut Program in Canada is relatively new compared with USA and Russia. Canadian Astronauts Roberta Bondar Chris Hadfield Marc Garneau Julie Payette Knowledge and Technology Knowledge of the universe is the result of centuries of observation and data collection using more and more advance d technologies. It is an ongoing process. Technologies that have Increased Knowledge of the Universe Hubble Space Telescope: Placed in Earth’s orbit and with no air (pollution etc.) to spoil the view, this has given amazing views of far away galaxies and stars in space Using this they were able to find that the universe is between 13 and 14 billion years old Light reaching its mirrors has not been distorted by Earth’s atmosphere Hubble Telescope Technologies that has increased knowledge The Very Large Array Radio Telescope: Made up of 27 antennas that are each 25 m across. The result is the same as one giant radio telescope that is 36 Km wide Radio telescope reveals characteristics of celestial bodies that could not be studied using optical telescopes like the previous two telescopes Dust in space makes it difficult to see light from distant stars but this telescope is not affected by dust (uses radio waves). Using this, we get a clearer picture. Radio Telescope Technologies … Canada-France-Hawaii Telescope: located on the 42 00 m dormant volcano in Hawaii. Above most of the air, giving a clearer view and providing cloud free skies. Technologies… Probes : A space vehicle sent to other celestial bodies. Used to travel million of kilometers, to analyze distant objects and then send information back to Earth Technologies… Technologies and underlying science Technology Chemistry Biology Physics Rockets Space Suits Satellites Probes Rovers Optical Telescopes Radio Telescopes The next Six slides will help fill out this table. Geology Other Technologies and underlying science used to Explore Space Rocket is a system used for transporting materials and astronauts into space Filled with explosive fuels (chemistry)that combine to generate thrust, the force (physics) that pushes against the rocket to get it to move As fuel is used up, some of the rocket is lost to make it lighter Technologies and underlying science Space Suits: acts as a smaller space ship, providing oxygen (chemistry) to breathe Contain a communication system to talk to each other and people on Earth (radio waves, physics) a cooling system and a system to simulate the air pressure on Earth’s Surface (air pressure, physics) Technologies and underlying science Satellites are electronic devices put in orbit around Earth to relay information. Communications satellites use electromagnetic radiation is used to send information from one place to another (involves physics) Technologies and underlying science Rovers: are small movable probes designed to land on a planet, explore and test the surface and send the information back to Earth by radio waves. They conduct experiments in geology (determining the make up of rocks) and biology (looking for signs of life) Technologies and underlying science Optical telescopes: use the property of light (physics) to get a better picture of the universe. Hubble space telescope is in Earth’s orbit. This also uses electromagnetic waves from the field of physics to send information back to Earth. Technologies and underlying science Radio Telescopes: Radio signals coming from distant objects are collected and converted to electrical symbols (physics again) and analyzed. Core Lab Designing a Space Station