(A) Topic 11 study these Flashcards

1
Q

What are asteroids between Mars and Jupiter thought to be formed from?

A

Debris of an old planet or raw materials of a forming planet that failed due to Jupiter’s gravitational influence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe the composition of asteroids

A

Consist of iron, rock and silicate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Name the parts of a comet

A

Nucleus, coma, ion tail, dust tail

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

When does a comet form its tails?

A

As it gets closer to the sun

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the names of comet tails and how are they formed?

A

Dust tail: radiation pressure
Ion tail: particles from solar wind hit the comet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the differences between the comets two tails?

A

Dust tail is brighter and more curved, whereas ion tail is more coloured but straighter than the dust tail

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is unusual about the orbit of comets compared to those of planets?

A

Comets have an inclined orbit: at a higher/lower angle to the elliptical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Explain the position of the Kuiper Belt

A

Outside Neptune’s orbit. Possibly 100-1000 AU

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Explain the position of the Oort cloud

A

Spherical region 10,000 to 20,000 AU

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Explain the type of bodies thought to originate from the Kuiper Belt and Oort Cloud

A

Kuiper Belt: where large bodies such as Pluto reside temporarily + short period comet origin
Oort cloud: source of long period comets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the heliosphere?

A

Extended feature of the sun’s influence. Bubble surrounding the solar system created by solar wind

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the three ways a satellite can be formed?

A

1) Forms in the same space as the planet
2) Captured by the planet
3) Evolves from the debris of the planet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe the composition of Gas Giants

A

Rocky core and the largest have an outer core of liquid metallic hydrogen (larger) or ammonia (smaller)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How were gas giants formed?

A

Gas from the Sun’s formation travelled further and further, gas giants evolved by accreting more gas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are meteoroids?

A

An object in space that will eventually become a meteor. There are two main kinds:
cometary meteoroid: small particles shed by the comet
asteroidal meteoroid: particles fallen off/ chipped off asteroids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are meteorites?

A

Meteor which survives entry into the Earth’s atmosphere.
- Most aren’t observed + fall into the ocean
- made of stone or iron with smooth exteriors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the difference between elliptic and ecliptic?

A

Ecliptic: imaginary line between Earth and the Sun
Elliptic: oval shape, rounded like an egg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are ingress and egress points?

A

The moment a body starts and ends its transit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How did scientists come up with an accurate measurement of the AU?

A

By taking multiple observations of the transit of a body and using geometry based on said observations, we can calculate the AU

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Why is liquid water important for life?

A

It is a solvent and allows various chemicals to form

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the two main theories about the origin of water?

A

Comets: since the Earth was heavily bombarded by comets, the comets containing large amounts of ice would’ve fed our oceans on impact
Condensation: claims water was part of the Earth’s body when it formed

22
Q

Why is our eye limited when it comes to naked eye observations?

A

Due to the size of our pupils

23
Q

What do telescopes allow us to do?

A

To see finer details of objects far away such as the moon or planets

24
Q

What do telescopes contain to help us see far objects?

A

Lenses or mirrors which are placed at the end of the tube

25
Q

Compare and contrast convex and concave lenses

A

Convex lens: enlarge an image + viewed in another convex lens
Concave lens: mirror can capture light and focus it onto a point where it is viewed by a convex lens

26
Q

Compare and contrast reflectors and refractors

A

Refractors: uses a convex lens to capture and focus light - glass coated in a film
Reflectors: use a mirror (concave) to capture a focus light - made of glass with an aluminium coating

27
Q

Describe Galilean refracting telescopes

A

G uses a concave lens as an eyepiece, fixed focus, and a limited FOV

28
Q

Describe Keplerian refracting telescopes

A

K uses a convex lens, is larger or heavier - focusable but photos are inverted

29
Q

Describe Newtonian reflecting telescopes

A

N has two mirrors, a concave mirror + another mirror further up the tube at a 45-degree angle

30
Q

Describe Cassegrain reflecting telescopes

A

C reflects light onto a secondary mirror as well, which faces the primary mirror + reflects light onto it but focused through a small hole behind the primary

31
Q

Define aperture

A

The amount of light a telescope receives, diameter of its objective lens or mirror

32
Q

Why is the size of the aperture important?

A

The larger it is, the more light that enters the telescope, making objects brighter and increasing resolution

33
Q

What is light grasp?

A

The measure of a telescope’s ability to capture light by its objective element

34
Q

What is the equation for light grasp?

A

light grasp is directly proportional to area, which is directly proportional to the diameter of its objective lens squared

35
Q

What is the field of view?

A

the circle of sky visible through a telescope’s eyepiece

36
Q

Define the two types of FoVs

A

Apparent FoV: when it’s not connected to the telescope
Real FOV: when the eyepiece is attached to the telescope

37
Q

How do we calculate the real FOV?

A

apparent FOV/ magnification

38
Q

What is resolution of a telescope dependant on?

A

the objective element and proportional to its diameter

39
Q

What is used to determine the resolution of a telescope?

A
  • wavelength
  • diffraction of light
  • the quality of the telescope
  • contrast
  • brightness
  • observer’s eyesight
40
Q

How might astronomers test out angular resolution?

A

Seeing how closely related objects such as double stars can be separated by arc seconds

41
Q

How is resolution calculated?

A

wavelength/ diameter

42
Q

How is magnification calculated?

A

focal length of objective lens/ focal length of eyepiece

43
Q

What does magnification depend on?

A

Ratio of focal lengths

44
Q

What is the focal length of a telescope?

A

How far light travels inside the telescope before it reaches a focus point

45
Q

How does the focal point of a telescope affect its magnification?

A

Shorter the focal length, the greater the magnification

46
Q

Name some of the principal astronomical theories associated with Galileo

A
  • Galilean Moons - Jupiter’s Moons
  • Moon’s uneven and rugged surface of mountains and craters
47
Q

Which is more popular: reflectors or refractors?

A

Reflectors because:
- lenses suffer from lens sagging and are more expensive
- refractors suffer from chromatic aberration, which makes images blurred and unclear. Reflectors reduce said problem
- Focal length can be increased whilst maintaining a practical, smaller tube
- multiple mirrors reduce the amount of wavelengths absorbed and have less maintainance

48
Q

What is a fly-by and what are the pros and cons of one?

A

Sending a probe past bodies in space to find information about the body, eg: Voyagers 1
pro: array of sensors - measure + take images
cons: not all parts of the body can be measured

49
Q

What is an orbiter and what are the pros and cons of one?

A

Probe sent to the body and continually orbits it for the duration of its mission eg: Magellan (Venus)
pro: usually can observe the whole body
con: limited information about surface features

50
Q

What is an impactor and what are the pros and cons of one?

A

The probe sent to hit the body + usually an accompanying probe will analyse the impact. eg: Temple 1
pro: allows us to find the composition of the body
con: 2 probes are expensive

51
Q

What is a lander and what are the pros and cons of one?

A

Craft that can land on another object and explore the surrounding area, eg: Huygens on Titan
pro: can study immediate environment + take precise geological and meteorological readings
con: may have limited capacity

52
Q

What are ALSEPs?

A

Apollo Lunar Surface Experiments Package