Asteroids, Comets, and Meteors Astro Exam 2
How long is the period of short period comets? long?
<200 years, longer
Which of the following is a truthful description of the physical appearance of a comet? A) comets develop a tail only when they get closer to the Sun in their orbit B) all comets are short period comets C) comets emerge from the sun D) the brightness of comets stays the same throughout their life
A
What is a meteorite?
A meteor that passes through the Earth's atmosphere and survives to hit the Earth
What is the size of the head of a comet and what is it made of?
About the size of a city and is made of frozen gases, rock and dust
Most meteors:
Are very small (centimeter scale) pieces of rock burning in the Earth's atmosphere
Most meteorites come from
Asteroids
Most orbit the sun between mars and Jupiter
Asteroids
Most orbit the sun in slightly elliptical orbits
Asteroids
Shine because of reflected sun
Asteroids and comets
Some are bigger than a mile in diameter
Asteroids and comets
Always within our solar system
Asteroids and meteors
Do not contain significant amount of icy gas
Asteroids and meteors
Mostly made of rock
Asteroids and meteors
Tail always points away from the sun, how do they form
Comet, due to solar wind
Come from the Kuiper Belt or Oort Cloud into the solar system
Comets
Icy objects
Comets
A comet's nucleus is composed of:
Dust, dry ice, and water ice
Asteroids are found where:
Found in high concentration in an asteroid belt between the orbits of Mars and Jupiter
What is true about Halley's comet?
It is a short period comet that will be seen in 2061
What was an accurate description of the KT event?
Living forms, notably the dominant ones such as the dinosaurs, were driven to extinction by the aftermath of the impact more than the impact itself
Also known as shooting stars
Meteors
Less than 100 meters in diameter
Meteors
Most burn up as they enter earth's atmosphere
Meteors
Streak across the sky at up to 100 thousand km per hour
Meteors
What are always within our solar system?
Meteors and asteroids
What is the size of a meteor?
Most are between the size of a small grain and a large boulder
The material of a meteorite is:
Roughly as old as the solar system
Asteroids are structured how
Solid, rocky, or metallic and they can have craters
What is the largest asteroid?
Vesta
How large are comets
a few kilometers in size
What are asteroids
are rocky materials left over from the early formation of our solar system
When is a meteor a meteoroid?
as they are hurtling through space
Most are less than 1 km but some can be bigger
asteroid
Three places asteroids can be
asteroid belt, Trojans, near-earth asteroids
KT event
asteroid collision 65 million years ago
What is remnants of the formations of the solar system?
asteroids, comets and meteors
What are the two types of asteroids?
carbon and silicate
Orbit the sun in highly elliptical orbits
comets
A meteor shower can occur when:
earth's orbit crosses a trail of decries left behind from a comet
What happens when an orbit of some asteroids intersect earth's orbit?
lead to meteors
how fast are comets
move slowly across the sky
how do we see asteroids
reflected sunlight
How fast are asteroids?
slow
where do long period comets come from? how far from the sun?
the Oort cloud, 50,000 AU
What are meteors
tiny dust particles burn up in earth's atmosphere
fireball
very bright meteor due to larger chunk of debirs
