Science vocabulary & information for teachers
Part Two by Elaine Gallagher This information is taken from Elaine Gallagher’s book, MY VERY FIRST ENGLISH ATLAS, published in 2009 by the Secretaria de […]
by Elaine Gallagher
This information is taken from Elaine Gallagher’s book, MY VERY FIRST ENGLISH ATLAS, published in 2009 by the Secretaria de Educación y Cultura de Coahuila, with copies donated to 300,000 primary school children in Coahuila, Mexico.
(You can teach this data to your students, so they’ll see how SMART you are!)
Let’s look at the COSMOS
Planets, moons, stars, meteors, asteroids, and black holes
1. What is a planet?
A planet is a huge ball of elements, minerals, rocks, and/or gases that revolve around a star, or around several stars that are close together. To be designated as a planet, scientists decided that they should have a size of more than 3,000 miles (4,800 Km) in diameter.
Because PLUTO is only 1,423 miles in diameter (2,290 km) it was taken off the list of official planets in 2006 because it was considered by scientists to be too small to qualify as a planet.
2. What is a moon?
A moon is a natural (NOT man-made) satellite of a planet. It revolves around a planet, the same way that the Earth revolves around the Sun.
3. How many moons does each planet have?
PLANET NUMBER OF MOONS
Jupiter 16 (maybe more)
Saturn 8 (maybe more)
(TEACHER: Show a photo of the Earth and the moon.)
4. How far is the moon from the Earth?
The path of the moon around the Earth is not perfectly round; it is elliptical (like an oval). For that reason, the distance varies between 221,463 miles (356,334 km) from Earth to 251,968 miles (405,503 km).The average distance of the moon from the Earth is 238,857 miles (384,392 km).
5. What is the size of our moon?
The moon is 27% of the size of the Earth, so the Earth is approximately 4 times larger than the moon.
(TEACHER: Show a model of the Earth and the moon, with the earth 4 times larger than the moon. HAVE STUDENTS DRAW EARTH AND MOON, SHOWING THIS SIZE PROPORTION. )
The moon’s diameter is 2,159 miles (3,475 km).
The moon’s circumference is 6,790 miles (10,864 km).
6. Is a DAY the same on all the planets?
NO! A «day» is how long it takes a planet to revolve one complete turn on its axis. (An «axis» is an imaginary pole through the center of planet, north to south.)
Our planet, Earth, takes about 24 hours (exactly 23 hours and 56 minutes) to make a complete turn. That is Earth’s «day».
Here is a chart to study and compare length of days:
PLANET EARTH DAYS LENGTH OF DAY
Mercury 58 15 30
Venus 243 0 32
Earth 23 56
Mars 24 37
Jupiter 9 50
Saturn 10 39
Uranus 17 14
Neptune 16 03
7. How far are the planets from the Sun?
PLANET AVERAGE DISTANCE FROM SUN
Mercury 35,983,000 57,909,100
Venus 67,237,700 108,208,600
Earth 92,955,900 149,598,000
Mars 41,634,800 227,939,200
Jupiter 483,612,200 778,298,400
Saturn 888,184,000 1,427,010,000
Uranus 1,782,000,000 2, 869,600,000
Neptune 3,666,000,000 5,913,490,000
8. How long do the planets take to go around the sun?
The planets revolve around the Sun in oval, elliptical orbits (paths), not in a perfect circle. For this reason, sometimes planets are closer to the Sun than at other times. Sometimes, planets even cross the path of other planets. The distances given in the chart below are the average distance from the Sun, starting with Mercury, the planet closest to the sun, and moving outward.
TEACHER: Draw a diagram showing the orbits of these planets around the sun. Then make a box labeled: «TRY THIS ACTIVITY»
Students: Draw a circle to represent a planet. Then draw a circle outside the planet, all the way around it. Do you see how the planet is the same distance from the circle at all points?
Now: Draw another planet, and this time, draw an oval (elliptical) all the way around it.
Do you see how the planet is closer to the line you drew in some places than others? This is how the paths (orbits) are in the 8 planets around our SUN.
9. What are the diameters of the planets?
(The diameter is the distance through the middle of the planet, as if you were slicing across the equator.)
Mercury 3,031 4,878
Venus 7,520 12,104
Earth 7,926 12,756
Mars 4,221 6,794
Jupiter 88,846 142,984
Saturn 74,898 120,536
Uranus 31,763 51,118
Neptune 31,329 50,530
Pluto 1,423 2,290
As you know, Pluto, since 2006, is no longer considered by scientists to be a planet because it is too small. It is just a body in space which revolves around the Sun as do others bodies, such as comets. We have included Pluto in this chart so you can see, from numbers, how much smaller it actually is than the other planets.
10. Which planets have «rings» around them?
Jupiter, Saturn, Uranus, and Neptune all have rings. (Rings are made of rocks, dust, and bits of gases or ice that surround some planets. Scientists think they are left from the «big bang».)
SATURN has the largest and most spectacular ring system, first discovered by Dutch astronomer, Christiaan Huygens (1629 – 1695).
Saturn’s rings are 169,800 miles (273,200 km) in diameter, but only 19 miles (16 km) thick. The rings appear to be composed of water ice ranging in size from tiny pieces to blocks of ice 10-20 yards in diameter. (A yard is 36 inches, a bit smaller than a meter, which is 39 inches.)
JUPITER’s rings were discovered by Voyager I spaceship in March 1979. The rings extend 80,240 miles (129,130 km) from the center of the planet. They are about 4,300 miles (7,000 km) in width and less than 20 miles (30 km) thick.
In 1977 scientists observed 9 rings around URANUS. Later, in 1986, Voyager 2 observed two more. The rings are thin, narrow, and very dark.
NEPTUNE has at least 4 rings, sighted by Voyager 2 in 1989.
11. What is a star?
A STAR is a burning ball of gases. There are stars that are much larger, and others that are much smaller, than our star, which we call the SUN.
When a star has planets that revolve around it in a regular path or orbit, it is called a «solar system», Our solar system is made up of one star, the SUN, and 8 planets, plus various space bodies, such as moons (that revolve around the planets), comets, asteroids, meteors, etc.
12. What is a meteor?
A meteor (sometimes called a shooting star) is the flash of light seen when an object passes through Earth’s atmosphere, and burns as a result of heating by friction.
13. What is a meteorite?
A meteorite is a natural object of extraterrestrial origin (comes from outer space) that survives passing through the Earth’s atmosphere and hits the earth’s surface.
14. What is a meteoroid?
A meteoroidis a small object in outer space, usually less than 30 feet (10 meters) in diameter.
A meteoroid becomes a meteor when it enters the Earth’s atmosphere.
If any portion of the meteoroid lands on Earth, it is a meteorite.
Some very large meteorites have been found on Earth. The largest known meteorite, weighing 66 Tons, was found in Namibia in Africa).
(A Ton = 2000 pounds!)
There have been three huge meteorites found in Mexico, (29.8, 15.4, and 12.1 tons), one in the USA, (15.4 Tons) and two in Greenland (33 and 22 tons).
15. What is an asteroid?
An asteroid, also called «minor planets» are smaller than any of the eight major planets. They are not satellites of any major planet; they orbit around the Sun.
The word Asteroid means «star-like» because asteroids appear to be points of light when they are seen through a telescope. Most asteroids, but not all, are located between Mars and Jupiter. This area in space is called the «asteroid belt».
CERES was the first asteroid to be discovered on January 1, 1802 by Giuseppe Piazzi (1746 – 1826). It has a diameter of 582 miles (936 km).
The smallest identified asteroid has a diameter of 0.62 miles (1 km).
Scientists have identified over 18,000 asteroids in space.
16. What is a comet?
A comet (sometimes called a «dirty snowball’) is a large clump, mainly made of ice, with some dust mixed in. When a comet moves in its orbit closer to the Sun, the dust and ice heat up, producing a tail of material that trails behind the comet. The tail is pushed out by the solar wind and almost always points away from the Sun.
(TEACHER: Show a picture or drawing of a comet.)
Most comets have an elliptical orbit (path) that carry them around the Sun, then to outer space, never to return.
Other comets, such as Halley’s Comet, have an orbit that causes it to return to the Earth’s view regularly every 76 years. Halley’s Comet was first identified by Edmund Halley (1656 – 1742) a Royal Astronomer for England.
Others had observed the comet for centuries, but they thought it was a sign for bad things to happen. Halley proved that comets are natural objects, subject to the laws of gravity. The last time Halley’s Comet appeared was in 1985-86. The next time will be 2061-62.
17. What is a black hole?
A black hole, named by USA physicist, John Wheeler, in 1967, is a gigantic part of outer space that was once a star that collapsed, (imploded). In its space is left a «black hole» , with such a strong, dense gravity force that even light can not escape.
Physicist, Albert Einstein (1879 – 1955), first predicted that when massive stars collapse, they will leave a huge space in their former location, and that this space will have the gravitational power to suck in anything nearby.
During his lifetime, Dr. Einstein was considered by many as the greatest living scientist, as Stephen Hawkings is today.
Einstein’s Theory of Relativity, (that the speed of light is a constant, and not relative to the observer or light source), and his equation about the relationship between mass and energy, E=MC2 (Energy equals Mass times C/the speed of light squared), changed human understanding of the physical world.
When a star with a mass greater than about 4 times that of our Sun uses up its gases, and eventually collapses, (over millions of years) there is nothing to stop the contraction, and the star collapses forever. The material is so dense that nothing, not even light can escape.
If a black hole existed near another star, it would suck matter from the other star to itself because the gravity-pull is so strong inside a black hole, producing x-rays which can be observed. That is the only way that the existence of a black hole can be observed, from the suns near it.
(TEACHER: Show a diagram of a black hole….)
18. Who is Stephen Hawking? (born 1943)
Dr. Stephen Hawking is a British physicist and mathematician, considered to be the greatest physicist of the late 20th and early 21st Centuries.
Despite a profound handicap (he has ALS, amyotrophic lateral sclerosis), which requires that he be in a wheel chair, Dr. Hawking has made major contributions to scientific knowledge through his research about black holes, and the origin of the universe. He is the author of several books, which he dictates on tape because of his severe physical problems. One of his most famous books that is easy and interesting to read for people who are NOT scientists, is A Brief History of Time.
END OF PART TWO