Vocabulary

Question 1

Perihelion

Answer 1

closest approach to the sun

Question 2

Aphelion

Answer 2

Furthest point from the sun

Question 3

Trojan

Answer 3

a trojan is a small celestial body (mostly asteroids) that shares the orbit of a larger one, remaining in a stable orbit approximately 60° ahead of or behind the main body near one of its Lagrangian points L4 and L5. Trojans can share the orbits of planets or of large moons.

Question 4

Kirkwood gaps

Answer 4

Kirkwood gap is a gap or dip in the distribution of the semi-major axes (or equivalently of the orbital periods) of the orbits of main-belt asteroids. They correspond to the locations of orbital resonances with Jupiter.

Question 5

Lagrange points

Answer 5

Lagrange points are positions in space where objects sent there tend to stay put. At Lagrange points, the gravitational pull of two large masses precisely equals the centripetal force required for a small object to move with them. These points in space can be used by spacecraft to reduce fuel consumption needed to remain in position.

Question 6

Refractory group

Answer 6

High melting points, low vapor pressures

Question 7

Troilite

Answer 7

FeS

Iron Sulphite

Question 8

Chondrite

Answer 8

A chondrite is a stony (non-metallic) meteorite that has not been modified, by either melting or differentiation of the parent body. They are formed when various types of dust and small grains in the early Solar System accreted to form primitive asteroids.

Question 9

3 Asteroid types

Answer 9

C-Type - Carbonaceous/Carbon-rich
M-Type - Metallic
S-Type - Sillicate

Question 10

Achondrite

Answer 10

An achondrite is a stony meteorite that does not contain chondrules. It consists of material similar to terrestrial basalts or plutonic rocks and has been differentiated due to melting and recrystallization on or within parent bodies.

Question 11

Meteorite Falls (NOT finds) distribution

Answer 11

Chondrites 86%
Achondites 9%
Irons 4%
Stony Irons 1%

Question 12

4 Achondrite Categories

Answer 12

Primitive (0.3)
Asteroidal (8)
Martian (0.5)
Lunar (rare)

Question 13

Main group of asteroidal achondrites

Answer 13

HED
Howardites, Eucrities, Diogenites
May originate from Vespa

Question 14

Milankovitch Insolation Cycles

3 factors

Answer 14

The Milankovitch cycles include:
The shape of Earth’s orbit, eccentricity;
The angle Earth’s axis is tilted with respect to Earth’s orbital plane, obliquity
The direction Earth’s axis of rotation is pointed, precession

Question 15

Field of view

Answer 15

Area that can be photographed in one go.

FOV = 2D x tan(θ/2)

Question 16

Resolution

Answer 16

Smallest feature that can be detected represented in meters/pixel

Question 17

3 ways to measure relative ages of planetary surfaces

Answer 17

1) Principle of superposition - Younger features usually overlie of cross-cut the older ones
2) Crater densities - can help identify how young or old different parts of the surface area relative to others by impact craters/square kilometer
3) Multi-Spectral Imaging - can be used to obtain information on mineral composition which can help date the surface
ABSOLUTE DATING IS NOT POSSIBLE

Question 18

Determining the height or depth of an object on a planet

Answer 18

h = shadow length x tan(theta)