P2g-threats to earth Flashcards
what is the earth moon system?
earth and other planet collide
iron cores merge to form the core of the earth
less dense material orbits as the moon
what is the evidence for the earth moon system?
moon has lower density than earth and doesn’t have a big iron core
moon rocks contain substances that evaporate at low temperatures suggesting the moon formed from hot material
what are some consequences of collision with a large asteroid?
crater ejection of hot rocks widespread fires sunlight blocked by dust climate change species extinction
what are asteroids?
rocks left over from formation of solar system
in orbit between mars and Jupiter
what is the evidence for past asteroid collisions?
layers of unusual elements in rocks
sudden changes in fossil numbers between adjacent layers of rock
Why is there an asteroid belt between mars and jupiter?
When the solar system was forming rocks between mars and jupiter didn’t form a planet
The gravitational attraction of jupiter disrupted the formation of a planet
What is a comet made up of?
Made from ice and dust
Has a tail formed from a trail of debris
What kind of orbits do comets have?
Highly elliptical orbits
Where do comets come from?
Objects orbiting the sun far beyond the planets
Why does a comet speed up as it approaches a star?
The subs gravitational pull increases as you get closer
What is an NEO?
Near earth object
Asteroid/comet on a possible collision course with earth
Why is it difficult to observe NEOs?
Small
Dark
Have unusual orbits
What actions could be taken to reduce the threat of NEOs?
Surveys by telescope
Monitoring by satellites
Deflection by explosions
Why is there an asteroid belt between mars and jupiter?
When the solar system was forming rocks between mars and jupiter didn’t form a planet
The gravitational attraction of jupiter disrupted the formation of a planet
What is a comet made up of?
Made from ice and dust
Has a tail formed from a trail of debris
What kind of orbits do comets have?
Highly elliptical orbits
Where do comets come from?
Objects orbiting the sun far beyond the planets
Why does a comet speed up as it approaches a star?
The subs gravitational pull increases as you get closer
What is an NEO?
Near earth object
Asteroid/comet on a possible collision course with earth
Why is it difficult to observe NEOs?
Small
Dark
Have unusual orbits
What actions could be taken to reduce the threat of NEOs?
Surveys by telescope
Monitoring by satellites
Deflection by explosions
