New Deck

Question 1

Types of conic sections

Answer 1

Circle, Ellipse, Parabola, Hyperbola

Question 2

What is Eccentricity?

Answer 2

Distance between foci / Major Axis; between 0 and 1; 0 indicates a circle

Question 3

What is the Semi-major axis?

Answer 3

1/2 the Major Axis and is the satellite’s mean distance from its primary

Question 4

Eccentricity, Semi-ajor Axis, Energy of: Circle

Answer 4

0, = radius, <0

Question 5

Eccentricity, Semi-ajor Axis, Energy of: Ellipse

Answer 5

0<e>0, &lt;0</e>

Question 6

Eccentricity, Semi-ajor Axis, Energy of: Parabola

Answer 6

1, infinity, 0

Question 7

Eccentricity, Semi-ajor Axis, Energy of: Hyperbola

Answer 7

>1, <0, >0

Question 8

What are the six orbital elements?

Answer 8

Semi-major axis, eccentricity, inclination, argument of periapsis, time of periapsis passage, longitude of ascending node

Question 9

What is inclination?

Answer 9

The angular distance between periapsis and the equatorial plane

Question 10

What is the convention with inclination?

Answer 10

0 is above the equator and prograde, 90 is polar, and 180 is retrograde

Question 11

What is periapsis?

Answer 11

The closest point in the orbit to the primary

Question 12

What is apoapsis?

Answer 12

The point in the orbit farthest from the primary

Question 13

What is the argument of periapsis?

Answer 13

The angular distance between the ascending node and periapsis

Question 14

What is the ascending node?

Answer 14

The point at which the orbit crosses the equator in a south to north direction

Question 15

What is the descending node?

Answer 15

The point at which the orbit crosses the equator in a north to south direction

Question 16

What is the longitude of the ascending node?

Answer 16

This is the angular distance between the ascending node and a reference point (the vernal equinox)

Question 17

What is the true anomaly?

Answer 17

The satellites angular distance past periapsis

Question 18

Describe this orbit

Geosynchronous (GEO)

Answer 18

Circular orbits with 24 hr period; ideal for communication of meteorological satellites

Question 19

Describe this orbit

Polar (PO)

Answer 19

Inclination of 90; ideal for mapping because as the earth orbits underneath the satellite has access to all locations on the surface

Question 20

Describe this orbit

Geostationary

Answer 20

Geosynchronous with an inclination of 0 so the satellites hovers above a point on the ground

Question 21

Describe this orbit

Walking

Answer 21

An orbit that takes advantage of other gravitational forces to precess

Question 22

Describe this orbit

Sun synchronous (SSO)

Answer 22

Walking orbits whose plane precesses with the same period as the planets solar orbit period. Thus the satellite crosses periapsis at the same local time every orbit

Question 23

Describe this orbit

Molniya

Answer 23

Highly eccentric with period of about 12 hrs. Orbital inclination chosen so that the rate of change of the perigee is 0, so apogee and perigee can be maintained over fixed latitudes.

Question 24

Describe this orbit

Hohmann transfer

Answer 24

Interplanetary trajectories that consume the least amount of propellant. To get to an outer planet, the spacecraft accelerates to a speed that places it into a heliocentric orbit with a aphelion equal to its targets. When it arrives it decelerates to be captured by the planet’s gravity. It is timed so that it arrives at its target planets orbital distance just as the planet itself arrives.

Question 25

How does g vary with altitude?

Answer 25

g = GM/r^2

Question 26

What is mu

Answer 26

The constant, GM