Science

April 13-17

 Kingfisher Science Encyclopedia 

Chapter 1. Planet Earth

Fossils and Geological Time - comprehension & finding information

1. What is a fossil?
    "... the preserved remains of a once living organism."
2. How old is the Earth?
    "...Earth's history began over 4.55 billion years ago."
3. What part of an organism usually survives to become fossils?
    "....usually only the hard parts such as shells or bones survive."
4. What is radioactive dating?
    "Some minerals can be accurately dated by calculating the amounts of radioactive elements within them... which decay at fixed rates."
5. What ended the Cretaceous period 66 million years ago?
    "...thousands of species, including dinosaurs... became extinct... an asteroid hit earth..."
6. What usually caused mass extinction events?
    "... mostly volcano induced climate change. Rarely... large asteroids or comets."
7. When did life on Earth begin?
    "... 3.8 billion years ago..." 

Bill Nye The Science Guy - S04E19 Fossils [link]

April 13-17

 Kingfisher Science Encyclopedia 

Chapter 1. Planet Earth

Earth and the Solar System - comprehension & finding information

1. What is a Solar System?
"A solar system consists of a star and the planets and other bodies that orbit around it." 
2. What is accretion?
"Earth formed from a disk of dust that surrounded the sun... the dust clumped together in a process called accretion."
3. What do scientists think cause the moon to form?
"...an object the size of Mars crashed into it. This threw a cloud of material into orbit, forming the moon."
4. What are the four inner planets in order form the sun?
"Mercury is the closest to the sun... next are Venus, Earth, and Mars."
5. What happened to water on Mars?
"... water froze or escaped into space and left a cold desert." 
6. Why is Venus so hot?
"Carbon dioxide in the atmosphere led to a greenhouse effect..." 

Q & A

Q: Does the planet Mercury contain the chemical mercury?
A: No, not in any significant amount. 

Q: Then why is it called 'Mercury'?
A: The planet is named after the Roman god 'Mercury' - messenger of the gods.

Q: Wait, isn't he Greek?
A: The Romans had different names for the same gods.

Q: Mercury is the smallest planet? What about Pluto?
A: Pluto is no longer considered a planet.

Q: Why not?
A: To be considered a planet, it must have these 3 characteristics;

    1. Orbit around the sun.
    2. Have enough mass to draw itself into a round shape.
    3. Must have cleared all other celestial bodies, except it's moons, from it's orbit.

Pluto is a "dwarf planet" in the Kuiper belt with it's own distinct orbit, but too small to be considered a real planet.

Q: What's the Kuiper belt?
A: A vast region of empty space beyond Neptune, home to icy, rocky objects left over from the formation of our solar system; including Pluto and thousands of other dwarf planets and comets. 

Kurzgesagt: Building a Marsbase is a Horrible Idea: Let's do it! [link] 

Earth's Rotation  - comprehension & finding information
1. What causes our seasons?
"... Earth spins like a top as it orbits out sun. These rotations cause... seasonal variations in sunlight and temperature."
2. What is a lunar month?
"The moon orbits the Earth in about 27 days... it takes 29 days (a lunar month)
to pass through all it's phases.
3. How long does it take the Earth to orbit the sun?
"Earth also orbits the sun in 356 1/4 days."
4. What is a lunar eclipse?
"...Earth comes between the sun and moon and the Earth casts a shadow on the moon."
5. What is a solar eclipse?
"A solar eclipse is when the moon comes between the Earth and the sun."
6. What causes tide?
"... the moon('s) gravity pulls water in the ocean towards it. The changes in water level... are called tides."
7. What are spring tides?
"Spring tides occur when the sun and the moon pull in the same direction."

Bill Nye The Science Guy - S01E15 Earth's Seasons [link]                 

Solar System (Observe & Copy, techniques)

Moon Phase Chart