Transcript 1. Amor asteroid

1. Amor asteroid
• -an asteroid whose orbit crosses the orbit of
Mars
2. Apollo asteroids
• asteroids whose orbits cross the orbit of
Earth.
3. asteroid
• rocky bodies orbiting between the orbits of
Mars and Jupiter
4. asteroid belt
• area between Mars and Jupiter where the
majority of asteroids can be found.
5. binary asteroid
• large asteroid orbited by a smaller satellite
body.
6. carbonaceous asteroid
• a darker asteroid containing more carbon
than most asteroids.
7. carbonaceous chondrite
• a carbonaceous asteroid containing chunks
of rocky material (chondrules).
8. carbonaceous meteorite
• dark meteorite with high carbon content.
9. chondrule
• rocky materials embedded in the interiors of
some carbonaceous meteorites.
10. coma
• brightest part of a comet, often called the
‘head’ of the comet.
11. comet
• a small body, composed mainly of ice and
dust, in an elliptical orbit about the Sun.
12. differentiated meteorite
• a meteorite where the denser materials have
moved to the center, usually as a result of
strong heating in the past, indicating the
meteorite was heated by geologic activity or
by a collision.
13. dust tail
• - comet’s tail composed of dust.
14. fall
• meteorite discovered on the ground after
being seen in the sky.
15. find
• meteorite discovered on the ground without
being seen in the sky.
16. Hirayama family
• a group of asteroids having the same orbit.
17. hydrogen envelope
• invisible region around a comet extending
millions of kilometers into space.
18. ion tail
• stream of ionized gas pushed away from the
head of a comet by the solar wind. (plasma
tail)
19. iron meteorite
• meteorite composed mainly of iron-nickel,
high-density.
20. Kirkwood gaps
• gaps in spacing of orbits of asteroids,
caused by gravitational resonance.
21. meteor
• a piece of interplanetary debris entering the
Earth’s atmosphere and burning up.
• A ‘shooting star’.
22. meteor shower
• many meteors seen each hour, caused by
Earth moving through cometary debris.
23. meteorite
• part of a meteoroid that survives the
atmosphere and lands on Earth
24. meteoroid
• interplanetary debris prior to entering the
Earth’s atmosphere
25. meteoroid swarm
• pebble-sized cometary fragments moving in
the same orbit as the parent comet.
26. micrometeoroid
• interplanetary debris from dust-sized to
pebble-sized.
27. nucleus
• solid region of ice and dust that makes up
the head of the comet.
28. Oort cloud
• material surrounding the solar system, out
to about 50,000 A. U. where comets
originate.
29. plasma tail
• ion tail.
30. primitive meteorite
• a stone meteorite showing no evidence of
heating in the past.
31. radiant
• constellation from whose direction a meteor
shower appears to come.
32. stone meteorite
• composition comparable to that of terrestrial
rocks.
33. stony-iron meteorite
• a mixture of iron and stone.
34. S-type asteroid
• made of silicate, or rocky material.
35. Sun-grazing comet
• a comet whose orbit takes it very close to
the Sun, at which point it may be destroyed.
36. Trojan asteroid
• asteroids locked into Lagrange points with
Jupiter, in the same orbit as Jupiter, 60
degrees ahead of and behind the planet.
37. type I tail
• ion tail, plasma tail; made of ionized gases,
straight.
38. type II tail
• dust tail; broad, diffuse, and curved.
1. What is the evidence of a high
potential for collisions of
asteroids with Earth?
• Apollo asteroids cross Earth’s orbit
• there are several dozen craters on Earth
that may have been impact sites
• other inner planets and moons show impact
sites.
2. What are Trojan asteroids?
• asteroids locked into Lagrange points with
Jupiter, in the same orbit as Jupiter, 60
degrees ahead of and behind the planet.
3. What are comets like when
they're far from the Sun? What
happens when they come into the
inner solar system?
• ‘Dirty snowballs’.
• The solar energy causes the ice to sublime.
4. What are the two types of
comet tails?
• Type I tails, ion tails, plasma tails. Straight,
made of ionized gasses.
• Type II tails, dust tails. Curved, made of
dust.
5. What are some possible fates
of comets?
• Can be broken up when near the Sun.
• Can crash into the Sun.
• Can gradually lose matter with each trip past
the Sun.
• Can be pulled out of orbit and crash into
another body (a planet).
6. Explain the difference between
a meteor, a meteoroid, and a
meteorite.
• A meteoroid is debris before it enters the
atmosphere;
• a meteor is debris that has entered the
atmosphere;
• a meteorite is a part of a meteor that survives
to hit the surface.
7. What causes a meteor
shower?
• The Earth passing through a young,
relatively undispersed cluster of meteoroids
(comet fragments).
8. What are the various types of
meteorites?
•
•
•
•
Differentiated meteorites,
primitive meteorites,
carbonaceous meteorites,
carbonaceous chondrites.
9. What are the most primitive
meteorites?
• Carbonaceous chondrites.
10. What have meteorites
revealed about our solar system?
• Being so old, they reveal the type of
materials present at the formation of the solar
system.