Week 3 Flashcards
What do elliptical orbits indicate?
An evolving solar system
What do circular orbits indicate?
A stable solar system
Mercury atmosphere and surface
No atmosphere, solid surface
Jovian planet features
Larger, lower density, no solid surface, mostly made of H/He, colder, many rings and moons
Terrestrial planet features
Smaller, higher density, solid surface, mostly made of metal and rocks, warmer, not many moons
Mars atmosphere
thin so won’t protect from radiation, no oxygen
Closest planet in size to earth
Venus
Nebular theory
Solar system formed from the gravitational collapse of a gas cloud
Nebular theory, Cloud rotation
as the cloud condensed in out solar system formation, it will spin faster (conservation of angular momentum)
Nebular theory, Flattening
Gravity will act on all directions of cloud, but the shortest side will collapse faster causing a flattened disk shape to form
How did planets form
Particle collisons casue objects to form, eventually causing planetesimals to form which gravity assembles into planets
Why are the composition of jovian and terrestrial plannets different?
Further out in the solar system the temperature is cooler, which results in substances staying as ice instead of melting, causing a different composition of planetesimals and more of them
Why is jupiter larger then saturn?
the further out you go in the solar system, the lower the density and hence the less effcient the process of planet formation
What are comets?
Mainly icey parts, left over from parts of outer solar system
What are asteroids?
Mainly rock parts, left over from parts of inner solar system
Commet tails
1 - ion tail, pointing directly away from sun
2 - sunlight reflected from melting stuff from commet
The planet closest to Earth in size is
venus
Where did the elements heavier than Hydrogen and Helium come from?
they closest inside stars
What are the main constituents of the jovian planets?
Hydrogen and helium
Based on our current theory of the formation of the Earth, the water we drink came from
Comets that hit the earth
Which of the following is NOT an observed motion of the planets in our Solar System?
- Most planets move at the same speed
- All planets orbit the Sun in the same direction
- Most planets lie in approximately the same plane
- Most planets rotate in the same direction that they orbit
Most planets move at the same speed
Which planet has a ring system? Jupiter Saturn Uranus Neptune
all of them
Which is these facts is NOT explained by the nebular theory?
- There are two main types of planets: terrestrial and jovian
- Planets orbit in the same direction and plane
- Existance of comets and asteroids
- Number of planets of each type (4 terrestrial and 4 jovian)
Number of planets of each type (4 terrestrial and 4 jovian)
Which planet has the highest average surface temperature and why?
Venus because of its dense atmosphere of carbon dioxide
